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COVID-19 pandemic in India

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138-536: The COVID-19 pandemic in India is a part of the worldwide pandemic of coronavirus disease 2019 ( COVID-19 ) caused by severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ). As of 27 November 2024, according to Indian government figures, India has the second-highest number of confirmed cases in the world (after the United States of America ) with 45,044,346 reported cases of COVID-19 infection and

276-625: A healthy diet are also recommended. Supportive care in severe cases includes treatment to relieve symptoms , fluid therapy , oxygen support and prone positioning , and medications or devices to support other affected vital organs. More severe cases may need treatment in hospital. In those with low oxygen levels, use of the glucocorticoid dexamethasone is recommended to reduce mortality. Noninvasive ventilation and, ultimately, admission to an intensive care unit for mechanical ventilation may be required to support breathing. Extracorporeal membrane oxygenation (ECMO) has been used to address

414-627: A variant of concern (VoC) or a variant of interest (VoI). Many of these variants have shared the more infectious D614G . As of May 2023, the WHO had downgraded all variants of concern to previously circulating as these were no longer detected in new infections. Sub-lineages of the Omicron variant (BA.1 – BA.5) were considered separate VoCs by the WHO until they were downgraded in March 2023 as no longer widely circulating. As of 24 September 2024 ,

552-403: A 5-month high as of 23 March and came amid an ongoing H3N2 influenza outbreak, prompting officials to determine the readiness of the healthcare system and its logistical needs. In response to the rising number of cases, some hospitals reopened Covid wards that had previously been shuttered following a yearlong lull in infections. In August, a new subvariant of Omicron, named Eris was detected in

690-521: A COVID-19 test at a private lab after a qualified physician in a government facility recommended it. Experts said this increased testing may ultimately result in a correction of the current under-counting and an increase in confirmed cases. 111 additional labs for testing became functional on 21 March. On 24 March, Mylab Discovery Solutions became the first Indian company to have received regulatory validation for its RT-PCR tests. In April, Institute of Genomics and Integrative Biology , Delhi had developed

828-493: A comprehensive international study. Such deaths include deaths due to healthcare capacity constraints and priorities, as well as reluctance to seek care (to avoid possible infection). Further research may help distinguish the proportions directly caused by COVID-19 from those caused by indirect consequences of the pandemic. In May 2022, the WHO estimated the number of excess deaths by the end of 2021 to be 14.9 million compared to 5.4 million reported COVID-19 deaths, with

966-580: A consent form, while some states chose to relegate Covaxin to a "buffer stock" and primarily distribute the Oxford–AstraZeneca vaccine. Following the conclusion of its trial, the DCGI issued a standard emergency-use authorisation to Covaxin in March 2021. The slogan ' Dawai Bhi, Kadai Bhi' (trnsl; Vaccination and Precautions both are necessary) was used by the Indian Government. In April 2021,

1104-409: A disease has ceased to be endemic to a population, then natural infections no longer contribute to a reduction in the fraction of the population that is susceptible. Only vaccination contributes to this reduction. The relation between vaccine coverage and effectiveness and disease incidence can be shown by subtracting the product of the effectiveness of a vaccine and the proportion of the population that

1242-479: A disease, written as V c . Vaccines are usually imperfect however, so the effectiveness, E , of a vaccine must be accounted for: From this equation, it can be observed that if E is less than (1 − 1/ R 0 ), then it is impossible to eliminate a disease, even if the entire population is vaccinated. Similarly, waning vaccine-induced immunity, as occurs with acellular pertussis vaccines , requires higher levels of booster vaccination to sustain herd immunity. If

1380-657: A doctor in Kandivali, Mumbai, has treated thousands of patients with ivermectin. The Indian government infused ₹ 900 crore (equivalent to ₹ 11 billion or US$ 130 million in 2023) into the Department of Biotechnology in November 2020 to aid the development of a COVID vaccine. The 2021 budget of India also allocated ₹ 35,000 crore (equivalent to ₹ 410 billion or US$ 4.9 billion in 2023) for vaccine procurement. In January 2021,

1518-673: A doctor, nurse or hygiene worker dies during treatment, their family will be provided ₹ 10 million (US$ 120,000). The Union government also announced the distribution of rations. COVID-19 pandemic The COVID-19 pandemic (also known as the coronavirus pandemic and COVID pandemic ), caused by severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ), began with an outbreak of COVID-19 in Wuhan , China, in December 2019. It spread to other areas of Asia, and then worldwide in early 2020. The World Health Organization (WHO) declared

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1656-432: A greater risk of developing complications from infection because of their medical status, but they may still be protected if a large enough percentage of the population is immune. High levels of immunity in one age group can create herd immunity for other age groups. Vaccinating adults against pertussis reduces pertussis incidence in infants too young to be vaccinated, who are at the greatest risk of complications from

1794-519: A lack of knowledge among poorer, rural communities has also impacted the programme. The second wave placed a major strain on the healthcare system , including a shortage of liquid medical oxygen due to ignored warnings which began in the first wave itself, logistic issues, and a lack of cryogenic tankers. On 23 April, Modi met via videoconference with liquid oxygen suppliers including Reliance , SAIL, JSW, Tata Steel , JSPL, AMNS, LINDE, INOX Air Products and Air Water Jamshedpur, where he acknowledged

1932-595: A large number of people". During the COVID-19 pandemic, as with other pandemics, the meaning of this term has been challenged. The end of a pandemic or other epidemic only rarely involves the total disappearance of a disease, and historically, much less attention has been given to defining the ends of epidemics than their beginnings. The ends of particular epidemics have been defined in a variety of ways, differing according to academic field, and differently based on location and social group. An epidemic's end can be considered

2070-401: A level beyond what can be predicted from direct protection alone, indicating that herd immunity contributed to the reduction. When serotype replacement is accounted for, it reduces the predicted benefits of vaccination. Herd immunity was recognized as a naturally occurring phenomenon in the 1930s when it was observed that after a significant number of children had become immune to measles ,

2208-423: A limited number of other individuals. In these networks, transmission only occurs between those who are geographically or physically close to one another. The shape and size of a network is likely to alter a disease's HIT, making incidence either more or less common. Mathematical models can use contact matrices to estimate the likelihood of encounters and thus transmission. In heterogeneous populations, R 0

2346-717: A low cost paper-strip test that could detect COVID-19 within an hour. Each test would cost ₹ 500.00 (equivalent to ₹ 590 or US$ 7.00 in 2023). On 13 April, ICMR advised pool testing in low infection areas to increase the capacity of the testing and save resources. In this process maximum five samples are tested at once and samples are tested individually only if a pool tests positive. Faulty test kits from China were subsequently returned and future orders cancelled. By 9 July 2020, 1132 testing labs were functional. Following testing shortages, non-accredited private laboratories applying for accreditation were also given permission to test for coronavirus. In September 2020, India had attained

2484-571: A major second wave of infections took hold in the country with destructive consequences; on 9 April, India surpassed 1 million active cases, and by 12 April, India overtook Brazil as having the second-most COVID-19 cases worldwide. By late April, India passed 2.5 million active cases and was reporting an average of 300,000 new cases and 2,000 deaths per-day. Some analysts feared this was an undercount. On 30 April, India reported over 400,000 new cases and over 3,500 deaths in one day. Multiple factors have been proposed to have potentially contributed to

2622-451: A median range of 0.24% to 1.49%. IFRs rise as a function of age (from 0.002% at age 10 and 0.01% at age 25, to 0.4% at age 55, 1.4% at age 65, 4.6% at age 75, and 15% at age 85). These rates vary by a factor of ≈10,000 across the age groups. For comparison, the IFR for middle-aged adults is two orders of magnitude higher than the annualised risk of a fatal automobile accident and much higher than

2760-441: A pathogen are transferred from one individual to another. This can occur naturally, whereby maternal antibodies, primarily immunoglobulin G antibodies, are transferred across the placenta and in colostrum to fetuses and newborns. Passive immunity can also be gained artificially, when a susceptible person is injected with antibodies from the serum or plasma of an immune person. Protection generated from passive immunity

2898-409: A person that he or she may not need to be vaccinated, since a sufficient percentage of others are already immune. Individuals who are immune to a disease act as a barrier in the spread of disease, slowing or preventing the transmission of disease to others. An individual's immunity can be acquired via a natural infection or through artificial means, such as vaccination. When a critical proportion of

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3036-442: A population for a sufficient time, the disease is inevitably eliminated – no more endemic transmissions occur. If elimination is achieved worldwide and the number of cases is permanently reduced to zero, then a disease can be declared eradicated. Eradication can thus be considered the final effect or end-result of public health initiatives to control the spread of contagious disease. In cases in which herd immunity

3174-577: A proportionate increase in disease incidence though, since NVTs were less invasive than VTs. Since then, pneumococcal vaccines that provide protection from the emerging serotypes have been introduced and have successfully countered their emergence. The possibility of future shifting remains, so further strategies to deal with this include expansion of VT coverage and the development of vaccines that use either killed whole-cells , which have more surface antigens, or proteins present in multiple serotypes. If herd immunity has been established and maintained in

3312-824: A random sample have consistently found that total infections considerably exceed the reported case counts. Many countries, early on, had official policies to not test those with only mild symptoms. The strongest risk factors for severe illness are obesity, complications of diabetes , anxiety disorders, and the total number of conditions. During the start of the COVID-19 pandemic it was not clear whether young people were less likely to be infected, or less likely to develop symptoms and be tested. A retrospective cohort study in China found that children and adults were just as likely to be infected. Among more thorough studies, preliminary results from 9 April 2020 found that in Gangelt ,

3450-574: A routine therapy, describing it is as an emerging and experimental therapy. Convalescent plasma therapy was dropped form the COVID-19 treatment protocol by ICMR in mid May 2021. In June 2020, India approved the repurposing of generic versions of the antiviral medication favipiravir for the treatment of mild-to-moderate COVID-19 symptoms by Glenmark , Cipla and the Indian Institute of Chemical Technology and Lupin Limited . In July 2020,

3588-410: A social phenomenon, not just a biological one. Time reported in March 2024 that expert opinions differ on whether or not COVID-19 is considered endemic or pandemic, and that the WHO continued to call the disease a pandemic on its website. During the initial outbreak in Wuhan , the virus and disease were commonly referred to as "coronavirus", "Wuhan coronavirus", "the coronavirus outbreak" and

3726-467: A specific population for medical reasons, but if both effectiveness and coverage are high enough then herd immunity can protect these individuals. Vaccine effectiveness is often, but not always, adversely affected by passive immunity, so additional doses are recommended for some vaccines while others are not administered until after an individual has lost his or her passive immunity. Individual immunity can also be gained passively, when antibodies to

3864-887: A stimulus package of ₹ 20,000 crore (equivalent to ₹ 240 billion or US$ 2.8 billion in 2023) to help the state overcome both the COVID-19 epidemic and economic hardship caused by it. On 21 March, Uttar Pradesh announced ₹ 1,000 (equivalent to ₹ 1,200 or US$ 14 in 2023) to all daily wage labourers. On 22 March, Punjab announced ₹ 3,000 (equivalent to ₹ 3,500 or US$ 42 in 2023) to all registered construction workers. A number of states and union territories went on to announce free and increased rations for ration card holders. Karnataka announced ₹ 1,610 crore (equivalent to ₹ 19 billion or US$ 230 million in 2023) relief for unorganised sectors including flower growers, washer-men and women, barbers, construction workers, auto and cab drivers, MSMEs , and weavers. The Delhi government announced that if

4002-451: A test. Conversely, deaths of people who died from underlying conditions following a positive test may be included. Countries such as Belgium include deaths from suspected cases, including those without a test, thereby increasing counts. Official death counts have been claimed to underreport the actual death toll, because excess mortality (the number of deaths in a period compared to a long-term average) data show an increase in deaths that

4140-504: A time period of six months, by August 2021. On 19 March 2021, in the Lok Sabha , the health minister of India stated that "It is not necessary, scientifically, to give each and every person in the country the vaccine. Not each and every person in the world will be vaccinated. The prioritisation process is a dynamic process..." Changes in procurement policies, the liberalised vaccination policy, and differential pricing further complicated

4278-798: A travel history to Italy and Germany, turned into a superspreader by attending a Sikh festival in Anandpur Sahib during 10–12 March. Over 40,000 people in 20 villages in Punjab were quarantined on 27 March to contain the spread. On 31 March, a Tablighi Jamaat religious congregation event in Delhi, which had taken place earlier in March, emerged as a COVID-19 hotspot . On 2 May, around 4,000 stranded pilgrims returned from Hazur Sahib in Nanded , Maharashtra to Punjab . Many of them tested positive, including 27 bus drivers and conductors who had been part of

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4416-435: A variety of reasons, including the belief that vaccines are ineffective, or that the risks associated with vaccines are greater than those associated with infection, mistrust of vaccines or public health officials, bandwagoning or groupthinking , social norms or peer pressure , and religious beliefs. Certain individuals are more likely to choose not to receive vaccines if vaccination rates are high enough to convince

4554-404: Is a form of indirect protection that applies only to contagious diseases . It occurs when a sufficient percentage of a population has become immune to an infection, whether through previous infections or vaccination , that the communicable pathogen cannot maintain itself in the population, its low incidence thereby reducing the likelihood of infection for individuals who lack immunity. Once

4692-518: Is associated with COVID-19 and is reported in as many as 88% of cases. The disease is mainly transmitted via the respiratory route when people inhale droplets and small airborne particles (that form an aerosol ) that infected people exhale as they breathe, talk, cough, sneeze, or sing. Infected people are more likely to transmit COVID-19 when they are physically close to other non-infected individuals. However, infection can occur over longer distances, particularly indoors. SARS‑CoV‑2 belongs to

4830-768: Is compromised, on the contrary, disease outbreaks among the unvaccinated population are likely to occur. The benefits of eradication include ending all morbidity and mortality caused by the disease, financial savings for individuals, health care providers, and governments, and enabling resources used to control the disease to be used elsewhere. To date, two diseases have been eradicated using herd immunity and vaccination: rinderpest and smallpox . Eradication efforts that rely on herd immunity are currently underway for poliomyelitis , though civil unrest and distrust of modern medicine have made this difficult. Mandatory vaccination may be beneficial to eradication efforts if not enough people choose to get vaccinated. Herd immunity

4968-651: Is considered to be a measure of the number of cases generated by a "typical" contagious person, which depends on how individuals within a network interact with each other. Interactions within networks are more common than between networks, in which case the most highly connected networks transmit disease more easily, resulting in a higher R 0 and a higher HIT than would be required in a less connected network. In networks that either opt not to become immune or are not immunized sufficiently, diseases may persist despite not existing in better-immunized networks. The cumulative proportion of individuals who get infected during

5106-611: Is discouraged altogether by the World Health Organization (WHO), due to limited evidence of its efficacy. The severity of COVID-19 varies. It may take a mild course with few or no symptoms, resembling other common upper respiratory diseases such as the common cold . In 3–4% of cases (7.4% for those over age 65) symptoms are severe enough to cause hospitalisation. Mild cases typically recover within two weeks, while those with severe or critical diseases may take three to six weeks to recover. Among those who have died,

5244-407: Is homogeneous, or well-mixed, meaning each individual is equally likely to come into contact with any other susceptible individual in the population, and S , the proportion of the population who are susceptible to infection, and setting this product to be equal to 1: S can be rewritten as (1 − p ), where p is the proportion of the population that is immune so that p + S equals one. Then,

5382-515: Is immediate, but wanes over the course of weeks to months, so any contribution to herd immunity is temporary. For diseases that are especially severe among fetuses and newborns, such as influenza and tetanus, pregnant women may be immunized in order to transfer antibodies to the child. In the same way, high-risk groups that are either more likely to experience infection, or are more likely to develop complications from infection, may receive antibody preparations to prevent these infections or to reduce

5520-402: Is immune to a disease in excess of that disease's HIT, the number of cases reduces at a faster rate, outbreaks are even less likely to happen, and outbreaks that occur are smaller than they would be otherwise. If the population immunity falls below the herd immunity threshold, where the effective reproduction number increases to above 1, the population is said to have an "immunity gap", and then

5658-405: Is integral, began as a way to immunize every person in a "ring" around an infected individual to prevent outbreaks from spreading. Since the adoption of mass and ring vaccination, complexities and challenges to herd immunity have arisen. Modeling of the spread of contagious disease originally made a number of assumptions, namely that entire populations are susceptible and well-mixed, which is not

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5796-439: Is intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), the virus that causes coronavirus disease 2019 ( COVID-19 ). Prior to the COVID-19 pandemic, an established body of knowledge existed about the structure and function of coronaviruses causing diseases like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). This knowledge accelerated

5934-450: Is low level transmission or moderate level transmission going on" but nothing as severe as before, in other words India is learning to live with the virus. India announced a mandatory 10-day quarantine on travellers arriving from United Kingdom irrespective of their vaccination status starting 4 October 2021 after United Kingdom also put the same restrictions on travellers from India by not recognizing India's vaccine certificate. On 8 October

6072-749: Is more severe in the elderly than in younger age groups, but influenza vaccines lack effectiveness in this demographic due to a waning of the immune system with age. The prioritization of school-age children for seasonal flu immunization, which is more effective than vaccinating the elderly, however, has been shown to create a certain degree of protection for the elderly. For sexually transmitted infections (STIs), high levels of immunity in heterosexuals of one sex induces herd immunity for heterosexuals of both sexes. Vaccines against STIs that are targeted at heterosexuals of one sex result in significant declines in STIs in heterosexuals of both sexes if vaccine uptake in

6210-490: Is not explained by COVID-19 deaths alone. Using such data, estimates of the true number of deaths from COVID-19 worldwide have included a range from 18.2 to 33.5 million (≈27.4 million) by 18 November 2023 by The Economist , as well as over 18.5 million by 1 April 2023 by the Institute for Health Metrics and Evaluation and ≈18.2 million (earlier) deaths between 1 January 2020, and 31 December 2021, by

6348-471: Is now inoculating children in the 12-15 age group. Further, the central government has urged state governments to end all COVID curbs except masks and social distancing. International flights were resumed on 27 March after a gap of two years. On 22 March 2023, Prime Minister Modi held a high-level meeting to discuss the nation's preparedness for a new wave of infections, potentially driven by the newly detected SARS-CoV-2 strain, XBB.1.16. Active cases had reached

6486-452: Is the ratio of deaths to diagnoses. This metric can be misleading because of the delay between symptom onset and death and because testing focuses on symptomatic individuals. Based on Johns Hopkins University statistics, the global CFR was 1.02 percent (6,881,955 deaths for 676,609,955 cases) as of 10 March 2023. The number varies by region and has generally declined over time. Several variants have been named by WHO and labelled as

6624-406: Is the seventh known coronavirus to infect people, after 229E , NL63 , OC43 , HKU1 , MERS-CoV , and the original SARS-CoV . The standard method of testing for presence of SARS-CoV-2 is a nucleic acid test , which detects the presence of viral RNA fragments. As these tests detect RNA but not infectious virus, its "ability to determine duration of infectivity of patients is limited." The test

6762-614: Is typically done on respiratory samples obtained by a nasopharyngeal swab ; however, a nasal swab or sputum sample may also be used. The WHO has published several testing protocols for the disease. Preventive measures to reduce the chances of infection include getting vaccinated, staying at home or spending more time outdoors, avoiding crowded places, keeping distance from others, wearing a mask in public, ventilating indoor spaces, managing potential exposure durations, washing hands with soap and water often and for at least twenty seconds, practising good respiratory hygiene, and avoiding touching

6900-543: Is vaccinated, p v , from the herd immunity threshold equation as follows: It can be observed from this equation that, all other things being equal (" ceteris paribus "), any increase in either vaccine coverage or vaccine effectiveness, including any increase in excess of a disease's HIT, further reduces the number of cases of a disease. The rate of decline in cases depends on a disease's R 0 , with diseases with lower R 0 values experiencing sharper declines. Vaccines usually have at least one contraindication for

7038-415: Is vulnerable to the free rider problem . Individuals who lack immunity, including those who choose not to vaccinate, free ride off the herd immunity created by those who are immune. As the number of free riders in a population increases, outbreaks of preventable diseases become more common and more severe due to loss of herd immunity. Individuals may choose to free ride or be hesitant to vaccinate for

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7176-458: Is when mutations accumulate in the portion of the viral genome that encodes for the virus's surface antigen , typically a protein of the virus capsid , producing a change in the viral epitope . Alternatively, the reassortment of separate viral genome segments, or antigenic shift , which is more common when there are more strains in circulation, can also produce new serotypes . When either of these occur, memory T cells no longer recognize

7314-724: The DCGI initially approved the Oxford–AstraZeneca vaccine , manufactured by the Serum Institute of India (SII) under the trade name "Covishield", and BBV152 (Covaxin), a vaccine developed by Bharat Biotech in association with the Indian Council of Medical Research and National Institute of Virology . The approval of Covaxin was met with some concern, as the vaccine had not then completed phase 3 trials. Due to this status, those receiving Covaxin were required to sign

7452-514: The Huanan Seafood Wholesale Market there, but it is possible that human-to-human transmission began earlier. Molecular clock analysis suggests that the first cases were likely to have been between October and November 2019. The scientific consensus is that the virus is most likely of a zoonotic origin, from bats or another closely related mammal. While other explanations such as speculations that SARS-CoV-2

7590-407: The Institute for Health Metrics and Evaluation estimating the true number of cases as of early 2022 to be in the billions. One measure that public health officials and policymakers have used to monitor the pandemic and guide decision-making is the test positivity rate ("percent positive"). According to Johns Hopkins in 2020, one benchmark for a "too high" per cent positive is 5%, which was used by

7728-546: The National Institute of Virology (NIV) isolated a strain of the novel coronavirus. India was the fifth country to successfully obtain a pure sample of the virus; isolation of the virus would help towards expediting the development of drugs, vaccines and rapid diagnostic kits in the country. NIV shared two SARS-CoV-2 genome sequences with GISAID . In May, the NIV introduced another test kit for rapid testing. Initially,

7866-566: The WHO confirmed that a novel coronavirus was the cause of a respiratory illness in a cluster of people in Wuhan, Hubei, China, which was reported to the WHO on 31 December 2019. On 30 January 2020, India reported its first case of COVID-19 in Thrissur , Kerala, which rose to three cases by 3 February 2020; all were students returning from Wuhan. Apart from these, no significant rise in transmissions

8004-602: The basic reproduction number (R 0 ) for COVID-19 in January 2020 were between 1.4 and 2.5, but a subsequent analysis claimed that it may be about 5.7 (with a 95 per cent confidence interval of 3.8 to 8.9). In December 2021, the number of cases continued to climb due to several factors, including new COVID-19 variants. As of that 28   December, 282,790,822 individuals worldwide had been confirmed as infected. As of 14 April 2022 , over 500 million cases were confirmed globally. Most cases are unconfirmed, with

8142-565: The basic reproduction number of the disease. An example of a disease with a high threshold was the measles, with a HIT exceeding 95%. The term "herd immunity" was first used in 1894 by American veterinary scientist and then Chief of the Bureau of Animal Industry of the US Department of Agriculture Daniel Elmer Salmon to describe the healthy vitality and resistance to disease of well-fed herds of hogs. In 1916 veterinary scientists inside

8280-433: The measles vaccine began in the 1960s. Mass vaccination, discussions of disease eradication, and cost–benefit analyses of vaccination subsequently prompted more widespread use of the term herd immunity . In the 1970s, the theorem used to calculate a disease's herd immunity threshold was developed. During the smallpox eradication campaign in the 1960s and 1970s, the practice of ring vaccination , to which herd immunity

8418-474: The variants of interest as specified by the World Health Organization are BA.2.86 and JN.1, and the variants under monitoring are JN.1.7, KP.2, KP.3, KP.3.1.1, JN.1.18, LB.1, and XEC. Symptoms of COVID-19 are variable, ranging from mild symptoms to severe illness. Common symptoms include headache, loss of smell and taste , nasal congestion and runny nose , cough, muscle pain , sore throat , fever, diarrhoea , and breathing difficulties . People with

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8556-460: The "Indian Supermodel", assuming that India reaches herd immunity . That month, a new SARS-CoV-2 variant , Lineage B.1.617 , was detected in the country. India began its vaccination programme on 16 January 2021. On 19 January 2021, nearly a year after the first reported case in the country, Lakshadweep became the last region of India to report its first case. By February 2021, daily cases had fallen to 9,000 per-day. However, by early-April 2021,

8694-429: The "Wuhan coronavirus outbreak", with the disease sometimes called "Wuhan pneumonia ". In January 2020, the WHO recommended 2019-nCoV and 2019-nCoV acute respiratory disease as interim names for the virus and disease per 2015 international guidelines against using geographical locations (e.g. Wuhan, China), animal species, or groups of people in disease and virus names in part to prevent social stigma . WHO finalised

8832-495: The 36 districts of 15 states which had reported positive cases among SARI patients. In April 2020 WHO placed India in the community transmission stage however in June moved India to clusters of cases. In October 2020, the health minister admitted to community transmission limited to some states and districts. Until May 2021, India insisted that clusters of cases remained, and there was no nationwide community transmission. On 23 March,

8970-530: The DCGI approved the Russian Sputnik V vaccine, which was trialled in India by Dr. Reddy's Laboratories . The initial shipment of 150 million Sputnik V doses arrived on 1 May, and began to be administered on 14 May. Domestic manufacturing of Sputnik V is expected to begin by August 2021, with doses imported from Russia being used in the meantime. In May 2021, the DCGI approved phase 2 and 3 trials of Covaxin among children 2–18. In late-June 2021, after

9108-620: The DCGI removed a requirement that all COVID-19 vaccines must be trialed locally before approval (notwithstanding any approval and wide use in other major countries), the DCGI approved the Moderna vaccine for emergency use. Administratively, India began preparing to vaccinate its population in April 2020 with the setting up a Vaccine Task Force. Following this the National Expert Group on Vaccine Administration for COVID-19 (NEGVAC)

9246-455: The HIT for a disease with an R 0 of 2 is theoretically only 50%, whereas a disease with an R 0 of 10 the theoretical HIT is 90%. When the effective reproduction number R e of a contagious disease is reduced to and sustained below 1 new individual per infection, the number of cases occurring in the population gradually decreases until the disease has been eliminated. If a population

9384-501: The Indian firm Biocon received emergency authorisation for the use of the repurposed drug Itolizumab in treatments for chronic plaque psoriasis , one of the symptoms of the disease. On 23 April 2021, Cadila Healthcare received an emergency authorisation to repurpose Peginterferon alfa-2b , a medication used to treat hepatitis C , as a treatment for moderate COVID-19 in adults. On 8 May 2021, DCGI gave permission for emergency use of

9522-720: The National Task Force for COVID-19 constituted by the ICMR recommended the use of hydroxychloroquine for the treatment of high-risk cases. In the same month, the Indian Institute of Chemical Technology , the Council of Scientific and Industrial Research (CSIR) and Cipla launched a joint venture to develop anti-COVID-19 drugs. In April, funds for a number of preventive agents were released to initiate research. The Centre for Cellular and Molecular Biology started working on genome sequencing of COVID-19 in early 2020. India

9660-475: The United Kingdom opened up the restrictions on travelers from 47 countries and locations including India. By March, India had just 22,487 cases across the country. With 58.8% population fully vaccinated and 70% having received at least one dose opening up post-pandemic has been steady. Buoyed by the success of its vaccination program among senior citizens, adults, and adolescents, the vaccination program

9798-588: The WHO in the past. As of 10 March 2023, more than 6.88   million deaths had been attributed to COVID-19. The first confirmed death was in Wuhan on 9 January 2020. These numbers vary by region and over time, influenced by testing volume, healthcare system quality, treatment options, government response, time since the initial outbreak, and population characteristics, such as age, sex, and overall health. Multiple measures are used to quantify mortality. Official death counts typically include people who died after testing positive. Such counts exclude deaths without

9936-419: The WHO, US, European Union, and Australia. On 12 November 2022, the WHO released its Global Vaccine Market Report. The report indicated that "inequitable distribution is not unique to COVID-19 vaccines"; countries that are not economically strong struggle to obtain vaccines. On 14 November 2022, the first inhalable vaccine was introduced, developed by Chinese biopharmaceutical company CanSino Biologics , in

10074-448: The broad family of viruses known as coronaviruses . It is a positive-sense single-stranded RNA (+ssRNA) virus, with a single linear RNA segment. Coronaviruses infect humans, other mammals, including livestock and companion animals, and avian species. Human coronaviruses are capable of causing illnesses ranging from the common cold to more severe diseases such as Middle East respiratory syndrome (MERS, fatality rate ≈34%). SARS-CoV-2

10212-602: The build up of immunity in populations to diseases such as diphtheria, scarlet fever, and influenza. Herd immunity was recognized as a naturally occurring phenomenon in the 1930s when A. W. Hedrich published research on the epidemiology of measles in Baltimore , and took notice that after many children had become immune to measles, the number of new infections temporarily decreased, including among susceptible children. In spite of this knowledge, efforts to control and eliminate measles were unsuccessful until mass vaccination using

10350-648: The centre of a major infection cluster in Germany, 15 per cent of a population sample tested positive for antibodies . Screening for COVID-19 in pregnant women in New York City , and blood donors in the Netherlands, found rates of positive antibody tests that indicated more infections than reported. Seroprevalence -based estimates are conservative as some studies show that persons with mild symptoms do not have detectable antibodies. Initial estimates of

10488-760: The city of Shanghai, China. For the first two years of the pandemic, no specific and effective treatment or cure was available. In 2021, the European Medicines Agency's (EMA) Committee for Medicinal Products for Human Use (CHMP) approved the oral antiviral protease inhibitor , Paxlovid (nirmatrelvir plus the HIV antiviral ritonavir ), to treat adult patients. FDA later gave it an EUA. Most cases of COVID-19 are mild. In these, supportive care includes medication such as paracetamol or NSAIDs to relieve symptoms (fever, body aches, cough), adequate intake of oral fluids and rest. Good personal hygiene and

10626-626: The country, and consists of the ministry's Emergency Medical Response Unit, the Central Surveillance Unit (IDSP) , the National Centre for Disease Control (NCDC) and experts from three government hospitals among others. In March 2020, India's strategy was focused on cluster-containment, similar to how India contained previous epidemics, as well as "breaking the chain of transmission". 52 labs were named capable of virus testing by 13 March. On 14 March 2020, scientists at

10764-402: The country. By late April, India led the world in new and active cases. On 30 April 2021, it became the first country to report over 400,000 new cases in a 24-hour period. Experts stated that the virus may reach an endemic stage in India rather than completely disappear; in late August 2021, Soumya Swaminathan said India may be in some stage of endemicity where the country learns to live with

10902-412: The course of a disease outbreak can exceed the HIT. This is because the HIT does not represent the point at which the disease stops spreading, but rather the point at which each infected person infects fewer than one additional person on average. When the HIT is reached, the number of additional infections does not immediately drop to zero. The excess of the cumulative proportion of infected individuals over

11040-484: The cumulative number of infected individuals (including asymptomatic and undiagnosed infections and excluding vaccinated infected individuals). It is expressed in percentage points. Other studies refer to this metric as the infection fatality risk . In November 2020, a review article in Nature reported estimates of population-weighted IFRs for various countries, excluding deaths in elderly care facilities, and found

11178-441: The development of various vaccine platforms during early 2020. The initial focus of SARS-CoV-2 vaccines was on preventing symptomatic and severe illness. The COVID-19 vaccines are widely credited for their role in reducing the severity and death caused by COVID-19. As of March 2023, more than 5.5 billion people had received one or more doses (11.8 billion in total) in over 197 countries. The Oxford-AstraZeneca vaccine

11316-513: The disease is neither in a steady state nor decreasing in incidence , but is actively spreading through the population and infecting a larger number of people than usual. An assumption in these calculations is that populations are homogeneous, or well-mixed, meaning that every individual is equally likely to come into contact with any other individual, when in reality populations are better described as social networks as individuals tend to cluster together, remaining in relatively close contact with

11454-494: The disease. The critical value, or threshold, in a given population, is the point where the disease reaches an endemic steady state , which means that the infection level is neither growing nor declining exponentially . This threshold can be calculated from the effective reproduction number R e , which is obtained by taking the product of the basic reproduction number R 0 , the average number of new infections caused by each case in an entirely susceptible population that

11592-523: The disease. This is especially important for close family members, who account for most of the transmissions to young infants. In the same manner, children receiving vaccines against pneumococcus reduces pneumococcal disease incidence among younger, unvaccinated siblings. Vaccinating children against pneumococcus and rotavirus has had the effect of reducing pneumococcus - and rotavirus -attributable hospitalizations for older children and adults, who do not normally receive these vaccines. Influenza (flu)

11730-555: The diseases they protect against and severe adverse effects are significantly less common than complications from natural infections. The immune system does not distinguish between natural infections and vaccines, forming an active response to both, so immunity induced via vaccination is similar to what would have occurred from contracting and recovering from the disease. To achieve herd immunity through vaccination, vaccine manufacturers aim to produce vaccines with low failure rates, and policy makers aim to encourage their use . After

11868-605: The drug 2-Deoxy-D-glucose developed by DRDO in collaboration with Dr. Reddy's Laboratories as an adjunct or alternative therapy for treating moderate to severe cases of COVID-19. By April 2021, the latest treatment guidelines mirrored those of the WHO and the United States with the important exception that, in India, mildly ill patients were allowed to be given Hydroxychloroquine or Ivermectin. This potential off-label prescription seems to have taken off in some parts of India: Kavery Nambisan, an Indian surgeon, said that

12006-575: The epicenter of the pandemic. Lockdowns were announced in Kerala on 23 March, and in the rest of the country on 25 March. Infection rates started to drop in September. Daily cases peaked mid-September with over 90,000 cases reported per-day, dropping to below 15,000 in January 2021. A second wave beginning in March 2021 was much more devastating than the first, with shortages of vaccines, hospital beds, oxygen cylinders and other medical supplies in parts of

12144-496: The equation can be rearranged to place p by itself as follows: With p being by itself on the left side of the equation, it can be renamed as p c , representing the critical proportion of the population needed to be immune to stop the transmission of disease, which is the same as the "herd immunity threshold" HIT. R 0 functions as a measure of contagiousness, so low R 0 values are associated with lower HITs, whereas higher R 0 s result in higher HITs. For example,

12282-513: The eyes, nose, or mouth with unwashed hands. Those diagnosed with COVID-19 or who believe they may be infected are advised by healthcare authorities to stay home except to get medical care, call ahead before visiting a healthcare provider, wear a face mask before entering the healthcare provider's office and when in any room or vehicle with another person, cover coughs and sneezes with a tissue, regularly wash hands with soap and water and avoid sharing personal household items. A COVID-19 vaccine

12420-509: The form of oxygen supplies, medicines, raw material for vaccines and ventilators. This reflected a policy shift in India, as comparable aid offers had been rejected during the past sixteen years. The number of new cases had begun to steadily drop by late-May; on 25 May, the country reported 195,994 new cases—its lowest daily increase since 13 April. However, the mortality rate has remained high; by 24 May, India recorded over 300,000 deaths attributed to COVID-19. Around 100,000 deaths had occurred in

12558-474: The general public beginning in December 2020, made available through government and international programs such as COVAX , aiming to provide vaccine equity . Treatments include novel antiviral drugs and symptom control. Common mitigation measures during the public health emergency included travel restrictions , lockdowns , business restrictions and closures, workplace hazard controls , mask mandates , quarantines, testing systems, and contact tracing of

12696-510: The herd immunity has been reached, disease gradually disappears from a population and may result in eradication or permanent reduction of infections to zero if achieved worldwide. Herd immunity created via vaccination has contributed to the reduction of many diseases. Some individuals either cannot develop immunity after vaccination or for medical reasons cannot be vaccinated. Newborn infants are too young to receive many vaccines, either for safety reasons or because passive immunity renders

12834-492: The highest number of daily tests in the world. By 5 May 2021, 2506 testing labs (government and private) were functional and the total daily national testing capacity reached 1,500,000 tests. Testing for community transmission began on 15 March 2020. 65 government laboratories started testing random samples of people who exhibit flu-like symptoms and samples from patients without any travel history or contact with infected persons. As of 18 March, no evidence of community transmission

12972-418: The impact of the virus. Models may have underestimated projected cases and deaths due to the under-reporting of cases in the country. Due to high demand, the vaccination programme began to be hit with supply issues; exports of the Oxford–AstraZeneca vaccine were suspended to meet domestic demand, there have been shortages of the raw materials required to manufacture vaccines domestically, while hesitancy and

13110-665: The infected. The pandemic caused severe social and economic disruption around the world, including the largest global recession since the Great Depression . Widespread supply shortages , including food shortages , were caused by supply chain disruptions and panic buying . Reduced human activity led to an unprecedented temporary decrease in pollution . Educational institutions and public areas were partially or fully closed in many jurisdictions, and many events were cancelled or postponed during 2020 and 2021. Telework became much more common for white-collar workers as

13248-487: The issue of respiratory failure. Existing drugs such as hydroxychloroquine , lopinavir/ritonavir , and ivermectin are not recommended by US or European health authorities, as there is no good evidence they have any useful effect. The antiviral remdesivir is available in the US, Canada, Australia, and several other countries, with varying restrictions; however, it is not recommended for use with mechanical ventilation, and

13386-437: The labs tested samples only from those with a travel history to 12 countries designated as high-risk, or those who had come in contact with anyone testing positive for the coronavirus, or showing symptoms as per the government guidelines. On 20 March 2020, the government decided to also include all pneumonia cases, regardless of travel or contact history. On 9 April, ICMR further revised the testing strategy and allowed testing of

13524-414: The last 26 days, and 50,000 in the last 12. In May 2021, WHO declared that two variants first found in India will be referred to as 'Delta' and 'Kappa'. The state of Karnataka announced a COVID-19 memorial later that spring, to honour healthcare professionals who had succumbed to the virus. On 25 August 2021, Soumya Swaminathan said that India "may be entering some kind of stage of endemicity where there

13662-576: The majority of the unreported 9.5 million deaths believed to be direct deaths due the virus, rather than indirect deaths. Some deaths were because people with other conditions could not access medical services . A December 2022 WHO study estimated excess deaths from the pandemic during 2020 and 2021, again concluding ≈14.8 million excess early deaths occurred, reaffirming and detailing their prior calculations from May as well as updating them, addressing criticisms. These numbers do not include measures like years of potential life lost and may make

13800-441: The need to "provide solutions in a very short time", and acknowledged efforts such as increases in production, and the use of rail, and air transport to deliver oxygen supplies. A large number of new oxygen plants were announced; the installation burden being shared by the center, coordination with foreign countries with regard to oxygen plants received in the form of aid, and DRDO. A number of countries sent emergency aid to India in

13938-421: The number of disease cases averted by vaccination. Study designs done to estimate herd immunity's benefit include recording disease incidence in households with a vaccinated member, randomizing a population in a single geographic area to be vaccinated or not, and observing the incidence of disease before and after beginning a vaccination program. From these, it can be observed that disease incidence may decrease to

14076-431: The number of new infections temporarily decreased. Mass vaccination to induce herd immunity has since become common and proved successful in preventing the spread of many contagious diseases. Opposition to vaccination has posed a challenge to herd immunity, allowing preventable diseases to persist in or return to populations with inadequate vaccination rates. The exact herd immunity threshold (HIT) varies depending on

14214-495: The official names COVID-19 and SARS-CoV-2 on 11 February 2020. Tedros Adhanom Ghebreyesus explained: CO   for corona , VI   for virus , D   for disease and 19 for when the outbreak was first identified (31 December 2019). WHO additionally uses "the COVID-19 virus" and "the virus responsible for COVID-19" in public communications. WHO named variants of concern and variants of interest using Greek letters . The initial practice of naming them according to where

14352-534: The outbreak a public health emergency of international concern (PHEIC) on 30 January 2020, and assessed the outbreak as having become a pandemic on 11 March. COVID-19 symptoms range from asymptomatic to deadly, but most commonly include fever, sore throat , nocturnal cough , and fatigue. Transmission of the virus is often through airborne particles . Mutations have produced many strains (variants) with varying degrees of infectivity and virulence . COVID-19 vaccines were developed rapidly and deployed to

14490-407: The pandemic 2021's leading cause of death . The time between symptom onset and death ranges from   6 to 41 days, typically about 14 days. Mortality rates increase as a function of age. People at the greatest mortality risk are the elderly and those with underlying conditions. The infection fatality ratio (IFR) is the cumulative number of deaths attributed to the disease divided by

14628-495: The pandemic evolved. Misinformation circulated through social media and mass media , and political tensions intensified . The pandemic raised issues of racial and geographic discrimination , health equity , and the balance between public health imperatives and individual rights . The WHO ended the PHEIC for COVID-19 on 5 May 2023. The disease has continued to circulate, but as of 2024, experts were uncertain as to whether it

14766-413: The people showing symptoms for a week in the hotspot areas of the country, regardless of travel history or local contact to a patient. While the health ministry claimed enough tests were being performed, experts disagreed, saying that community transmission may go undetected. On 17 March 2020, the health ministry decided to allow accredited private pathology labs to test for COVID-19. A person could get

14904-420: The population becomes immune, called the herd immunity threshold (HIT) or herd immunity level (HIL), the disease may no longer persist in the population, ceasing to be endemic . The theoretical basis for herd immunity generally assumes that vaccines induce solid immunity, that populations mix at random, that the pathogen does not evolve to evade the immune response, and that there is no non-human vector for

15042-415: The population's age structure and the age-specific pattern of infections. There have also been reviews that have compared the fatality rate of this pandemic with prior pandemics, such as MERS-CoV. For comparison the infection mortality rate of seasonal flu in the United States is 0.1%, which is 13 times lower than COVID-19. Another metric in assessing death rate is the case fatality ratio (CFR), which

15180-450: The production of novel strains, referred to as escape mutants, that are able to evade herd immunity and infect previously immune individuals. The evolution of new strains is known as serotype replacement, or serotype shifting, as the prevalence of a specific serotype declines due to high levels of immunity, allowing other serotypes to replace it. At the molecular level, viruses escape from herd immunity through antigenic drift , which

15318-462: The risk of dying from seasonal influenza . In December 2020, a systematic review and meta-analysis estimated that population-weighted IFR was 0.5% to 1% in some countries (France, Netherlands, New Zealand, and Portugal), 1% to 2% in other countries (Australia, England, Lithuania, and Spain), and about 2.5% in Italy. This study reported that most of the differences reflected corresponding differences in

15456-459: The same Bureau of Animal Industry used the term to refer to the immunity arising following recovery in cattle infected with brucellosis, also known as "contagious abortion." By 1923 it was being used by British bacteriologists to describe experimental epidemics with mice, experiments undertaken as part of efforts to model human epidemic disease. By the end of the 1920s the concept was used extensively - particularly among British scientists - to describe

15594-496: The same infection may have different symptoms, and their symptoms may change over time. Three common clusters of symptoms have been identified: one respiratory symptom cluster with cough, sputum , shortness of breath, and fever; a musculoskeletal symptom cluster with muscle and joint pain, headache, and fatigue; a cluster of digestive symptoms with abdominal pain, vomiting, and diarrhoea. In people without prior ear, nose, and throat disorders, loss of taste combined with loss of smell

15732-487: The severity of symptoms. Herd immunity is often accounted for when conducting cost–benefit analyses of vaccination programs. It is regarded as a positive externality of high levels of immunity, producing an additional benefit of disease reduction that would not occur had no herd immunity been generated in the population. Therefore, herd immunity's inclusion in cost–benefit analyses results both in more favorable cost-effectiveness or cost–benefit ratios, and an increase in

15870-616: The situation. Global vaccine obligations of India were also severely affected including those with south-Asian neighbours, and 190 countries associated with COVAX . By 22 October 2021, India delivered 1 Billion doses for COVID-19 out of which, 700 million were single doses and 300 million were double doses. According to a 2022 modelling study published in The Lancet Infectious Diseases journal , over 4.2 million lives were saved in India in 2021 due to vaccination against COVID-19. On 19 March 2020, Kerala announced

16008-543: The spread of the virus within the community, and mitigation strategies (commonly known as " flattening the curve ") that attempt to lessen the effects of the virus on society, but which still tolerate some level of transmission within the community. These initial strategies can be pursued sequentially or simultaneously during the acquired immunity phase through natural and vaccine-induced immunity . Herd immunity Herd immunity (also called herd effect , community immunity , population immunity , or mass immunity )

16146-592: The state of Maharashtra with cases increasing in a few cities. While in December, the JN.1 variant, believed to be a descendant of Omicron subvariant known as BA.2.86 or Pirola, arrived in the southern state Kerala with an RT-PCR-positive sample from Karakulam in Thiruvananthapuram district. The Union Health Ministry 's war room and policy making team in New Delhi decide how coronavirus should be tackled in

16284-404: The successful introduction and widespread use of a vaccine, sharp declines in the incidence of diseases it protects against can be observed, which decreases the number of hospitalizations and deaths caused by such diseases. Assuming a vaccine is 100% effective, then the equation used for calculating the herd immunity threshold can be used for calculating the vaccination level needed to eliminate

16422-469: The sudden spike in cases, including highly-infectious variants of concern such as Lineage B.1.617 , a lack of preparations as temporary hospitals were often dismantled after cases started to decline, and new facilities were not built, and health and safety precautions being poorly-implemented or enforced during weddings, festivals (such as Holi on 29 March, and the Haridwar Kumbh Mela which

16560-585: The target sex is high. Herd immunity from female vaccination does not, however, extend to males who have sex with males. High-risk behaviors make eliminating STIs difficult because, even though most infections occur among individuals with moderate risk, the majority of transmissions occur because of individuals who engage in high-risk behaviors. For this reason, in certain populations it may be necessary to immunize high-risk individuals regardless of sex. Herd immunity itself acts as an evolutionary pressure on pathogens, influencing viral evolution by encouraging

16698-471: The theoretical HIT is known as the overshoot . The primary way to boost levels of immunity in a population is through vaccination. Vaccination is originally based on the observation that milkmaids exposed to cowpox were immune to smallpox, so the practice of inoculating people with the cowpox virus began as a way to prevent smallpox. Well-developed vaccines provide protection in a far safer way than natural infections, as vaccines generally do not cause

16836-433: The third-highest number of COVID-19 deaths (after the United States and Brazil ) at 533,655 deaths. In October 2021, the World Health Organization estimated 4.7 million excess deaths, both directly and indirectly related to COVID-19 to have taken place in India. The first cases of COVID-19 in India were reported on 30 January 2020 in three towns of Kerala , among three Indian medical students who had returned from Wuhan ,

16974-411: The time from symptom onset to death has ranged from two to eight weeks. Prolonged prothrombin time and elevated C-reactive protein levels on admission to the hospital are associated with severe course of COVID-19 and with a transfer to intensive care units (ICU). Between 5% and 50% of COVID-19 patients experience long COVID , a condition characterised by long-term consequences persisting after

17112-457: The transport arrangement. In July 2020, it was estimated based on antibody tests that at least 57% of the inhabitants of Mumbai's slums may have been infected with COVID-19 at some point. A government panel on COVID-19 stated in October 2020 that the pandemic had peaked in India, and could come under control by February 2021. This prediction was based on a mathematical simulation referred to as

17250-694: The typical convalescence period of the disease. The most commonly reported clinical presentations are fatigue and memory problems, as well as malaise , headaches, shortness of breath , loss of smell, muscle weakness , low fever and cognitive dysfunction . Many countries attempted to slow or stop the spread of COVID-19 by recommending, mandating or prohibiting behaviour changes, while others relied primarily on providing information. Measures ranged from public advisories to stringent lockdowns. Outbreak control strategies are divided into elimination and mitigation. Experts differentiate between elimination strategies (known as " zero-COVID ") that aim to completely stop

17388-550: The vaccine ineffective. Individuals who are immunodeficient due to HIV/AIDS , lymphoma , leukemia , bone marrow cancer, an impaired spleen , chemotherapy , or radiotherapy may have lost any immunity that they previously had and vaccines may not be of any use for them because of their immunodeficiency. A portion of those vaccinated may not develop long-term immunity. Vaccine contraindications may prevent certain individuals from being vaccinated. In addition to not being immune, individuals in one of these groups may be at

17526-543: The variants were identified (e.g. Delta began as the " Indian variant") is no longer common. A more systematic naming scheme reflects the variant's PANGO lineage (e.g., Omicron 's lineage is B.1.1.529) and is used for other variants. SARS-CoV-2 is a virus closely related to bat coronaviruses , pangolin coronaviruses, and SARS-CoV . The first known outbreak (the 2019–2020 COVID-19 outbreak in mainland China ) started in Wuhan , Hubei, China, in December 2019. Many early cases were linked to people who had visited

17664-701: The virus, so people are not immune to the dominant circulating strain. For both influenza and norovirus , epidemics temporarily induce herd immunity until a new dominant strain emerges, causing successive waves of epidemics. As this evolution poses a challenge to herd immunity, broadly neutralizing antibodies and "universal" vaccines that can provide protection beyond a specific serotype are in development. Initial vaccines against Streptococcus pneumoniae significantly reduced nasopharyngeal carriage of vaccine serotypes (VTs), including antibiotic-resistant types, only to be entirely offset by increased carriage of non-vaccine serotypes (NVTs). This did not result in

17802-455: The virus. India began its vaccination programme on 16 January 2021 with AstraZeneca vaccine (Covishield) and the indigenous Covaxin . Later, Sputnik V and the Moderna vaccine was approved for emergency use too. On 30 January 2022, India announced that it administered about 1.7 billion doses of vaccines and more than 720 million people were fully vaccinated. On 12 January 2020,

17940-443: Was accidentally released from a laboratory have been proposed, as of 2021 these were not supported by evidence. Official "case" counts refer to the number of people who have been tested for COVID-19 and whose test has been confirmed positive according to official protocols whether or not they experienced symptomatic disease. Due to the effect of sampling bias , studies which obtain a more accurate number by extrapolating from

18078-508: Was estimated to have approximately 40,000 ventilators in March 2020, of which 8,432 were with the public sector. The government aimed to double the capacity of ventilators by June 2020, with the assistance from Indian PSUs , firms and startups, including Bharat Electronics , DRDO and ISRO . This led to the creation of some of the world's smallest and cheapest ventilators. Production lines were repurposed to manufacture general Personal protective equipment , full body suits and ventilators; India

18216-447: Was formed, and in October 2020 states were asked to set up state level mechanisms for the COVID-19 vaccine programme, and prepare cold chains points. A communication strategy for the vaccination programme was also revealed by the health ministry in January 2021, targeting issues such as vaccine eagerness and hesitancy. India started out with a vaccination policy targeting 300 million people based on occupation and age group, to be completed

18354-424: Was found after results of 500 random samples tested negative. Between 15 February and 2 April, 5,911 SARI (Severe Acute Respiratory Illnesses) patients were tested throughout the country of which, 104 tested positive (1.8%) in 20 states and union territories. About 40% of the identified patients did not have a travel history or any history of contact with a positive patient. The ICMR advised to prioritise containment in

18492-516: Was linked to at least 1,700 positive cases between 10 and 14 April including cases in Hindu seers), sporting events (such as IPL ), state and local elections in which politicians and activists have held in several states, and in public places. An economic slowdown put pressure on the government to lift restrictions, and there had been a feeling of exceptionalism based on the hope that India's young population and childhood immunisation scheme would blunt

18630-462: Was observed in February. On 4 March 22 new cases were reported, including 14 infected members of an Italian tourist group. Transmissions increased over the month after several people with travel history to affected countries, and their contacts, tested positive. On 12 March, a 76-year-old man, with a travel history to Saudi Arabia, became the first COVID-19 fatality of India. A Sikh preacher, who had

18768-486: Was producing around 200,000 PPE kits and 250,000 N95 masks per day in May 2020, compared to virtually zero shortly before. Several states were allowed by ICMR and Drugs Controller General of India (DCGI) to start clinical trials of convalescent plasma therapy and plasma exchange therapy . Initial optimism around plasma therapy, resulted in ICMR stating that there is no robust evidence to support convalescent plasma therapy as

18906-457: Was still a pandemic. Pandemics and their ends are not well-defined, and whether or not one has ended differs according to the definition used. As of 24 November 2024, COVID-19 has caused 7,075,455 confirmed deaths. The COVID-19 pandemic ranks as the fifth- deadliest pandemic or epidemic in history . In epidemiology , a pandemic is defined as "an epidemic occurring over a very wide area, crossing international boundaries, and usually affecting

19044-445: Was the most widely used. According to a June 2022 study, COVID-19 vaccines prevented an additional 14.4 million to 19.8 million deaths in 185 countries and territories from 8 December 2020 to 8 December 2021. On 8 November 2022, the first recombinant protein-based COVID-19 vaccine (Novavax's booster Nuvaxovid ) was authorised for use in adults in the United Kingdom. It has subsequently received endorsement/authorisation from

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