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115-401: Bubonic plague is one of three types of plague caused by the bacterium Yersinia pestis . One to seven days after exposure to the bacteria, flu-like symptoms develop. These symptoms include fever , headaches , and vomiting , as well as swollen and painful lymph nodes occurring in the area closest to where the bacteria entered the skin. Acral necrosis , the dark discoloration of skin,
230-504: A lymphoma or leukemia . Rarely, depending on location, lymph node enlargement may cause problems such as difficulty breathing, or compression of a blood vessel (for example, superior vena cava obstruction ). Enlarged lymph nodes might be felt as part of a medical examination , or found on medical imaging . Features of the medical history may point to the cause, such as the speed of onset of swelling, pain, and other constitutional symptoms such as fevers or weight loss. For example,
345-465: A plague outbreak in five Indian states caused an estimated 700 infections (including 52 deaths) and triggered a large migration of Indians within India as they tried to avoid the disease. It was during the 1894 Hong Kong plague outbreak that Alexandre Yersin isolated the bacterium responsible ( Yersinia pestis ), a few days after Japanese bacteriologist Kitasato Shibasaburō had isolated it. However,
460-404: A case of pneumonic plague may be treated with preventive medication. If infected, treatment is with antibiotics and supportive care . Typically antibiotics include a combination of gentamicin and a fluoroquinolone . The risk of death with treatment is about 10% while without it is about 70%. Globally, about 600 cases are reported a year. In 2017, the countries with the most cases include
575-471: A great risk of infection. Management of lymphedema may include advice to lose weight, exercise, keep the affected limb moist, and compress the affected area. Sometimes surgical management is also considered. The spleen and the tonsils are the larger secondary lymphoid organs that serve somewhat similar functions to lymph nodes, though the spleen filters blood cells rather than lymph. The tonsils are sometimes erroneously referred to as lymph nodes. Although
690-676: A human case of bubonic plague was reported. Officials responded by activating a city-wide plague-prevention system for the remainder of the year. Also in July 2020, in Mongolia, a teenager died from bubonic plague after consuming infected marmot meat. Yersinia pestis has been discovered in archaeological finds from the Late Bronze Age (~3800 BP ). The bacteria is identified by ancient DNA in human teeth from Asia and Europe dating from 2,800 to 5,000 years ago. Some authors have suggested that
805-494: A large population of rats, the animals can harbor low levels of the plague infection without causing human outbreaks. With no new rat inputs being added to the population from other areas, the infection only spread to humans in very rare cases of overcrowding. After being transmitted via the bite of an infected flea, the Y. pestis bacteria become localized in an inflamed lymph node , where they begin to colonize and reproduce. Infected lymph nodes develop hemorrhages, which result in
920-510: A lymphoid follicle, where they multiply and divide, each producing a different antibody. If a cell is stimulated, it will go on to produce more antibodies (a plasma cell) or act as a memory cell to help the body fight future infection. If a cell is not stimulated, it will undergo apoptosis and die. Antigens are molecules found on bacterial cell walls , chemical substances secreted from bacteria, or sometimes even molecules present in body tissue itself. These are taken up by cells throughout
1035-443: A mesh-work in the central or medullary portion of the node. These trabecular spaces formed by the interlacing trabeculae contain the proper lymph node substance or lymphoid tissue. The node pulp does not, however, completely fill the spaces, but leaves between its outer margin and the enclosing trabeculae a channel or space of uniform width throughout. This is termed the subcapsular sinus (lymph path or lymph sinus). Running across it are
1150-415: A meshwork or fibers called reticulum with white blood cells enmeshed in it. The regions where there are few cells within the meshwork are known as lymph sinus . It is lined by reticular cells, fibroblasts and fixed macrophages. Thin reticular fibers (reticulin) of reticular connective tissue form a supporting meshwork inside the node. These reticular cells also form a conduit network within
1265-497: A number of finer trabeculae of reticular fibers, mostly covered by ramifying cells. In the lymphatic system, a lymph node is a secondary lymphoid organ. The primary function of lymph nodes is the filtering of lymph to identify and fight infection. In order to do this, lymph nodes contain lymphocytes, a type of white blood cell, which includes B cells and T cells. These circulate through the bloodstream and enter and reside in lymph nodes. B cells produce antibodies . Each antibody has
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#17327653750801380-436: A part of the nodule in the medulla. The substance of a lymph node is divided into the outer cortex and the inner medulla . The cortex of a lymph node is the outer portion of the node, underneath the capsule and the subcapsular sinus. It has an outer part and a deeper part known as the paracortex . The outer cortex consists of groups of mainly inactivated B cells called follicles. When activated, these may develop into what
1495-436: A patient with pneumonic plague and were not wearing adequate personal protective equipment. Antimicrobial postexposure prophylaxis also can be considered for laboratory workers accidentally exposed to infectious materials and people who had close (<6 feet) or direct contact with infected animals, such as veterinary staff, pet owners, and hunters. Specific recommendations on pre- and post-exposure prophylaxis are available in
1610-405: A person receives antibiotics before a sample is collected for laboratory testing, they may have a false negative culture and a positive PCR result. Blood tests to detect antibodies against Y. pestis can also be used to diagnose plague, however, this requires taking blood samples at different periods to detect differences between the acute and convalescent phases of F1 antibody titres. In 2020,
1725-554: A rise in the rodent population. A 21st-century study of a 1665 outbreak of plague in the village of Eyam in England's Derbyshire Dales – which isolated itself during the outbreak, facilitating modern study – found that three-quarters of cases are likely to have been due to human-to-human transmission, especially within families, a much larger proportion than previously thought. Symptoms of plague are usually non-specific and to definitively diagnose plague, laboratory testing
1840-465: A role in controlling the 2003 Oran outbreak of the bubonic plague. Another means of prevention in large European cities was a city-wide quarantine to not only limit interaction with people who were infected, but also to limit the interaction with the infected rats. Several classes of antibiotic are effective in treating bubonic plague. These include aminoglycosides such as streptomycin and gentamicin , tetracyclines (especially doxycycline ), and
1955-514: A role in increasing the transmission effectiveness of the plague. The plague resurfaced for a third time in the mid-19th century; this is also known as "the modern pandemic". Like the two previous outbreaks, this one also originated in Eastern Asia , most likely in Yunnan , a province of China, where there are several natural plague foci . The initial outbreaks occurred in the second half of
2070-418: A series of sinuses. After entering the lymph node from afferent lymphatic vessels, lymph flows into a space underneath the capsule called the subcapsular sinus , then into cortical sinuses. After passing through the cortex, lymph then collects in medullary sinuses. All of these sinuses drain into the efferent lymph vessels to exit the node at the hilum on the concave side. Lymph nodes are present throughout
2185-403: A single predetermined target, an antigen , that it can bind to. These circulate throughout the bloodstream and if they find this target, the antibodies bind to it and stimulate an immune response. Each B cell produces different antibodies, and this process is driven in lymph nodes. B cells enter the bloodstream as "naive" cells produced in bone marrow . After entering a lymph node, they then enter
2300-463: A study about rapid diagnostic tests that detect the F1 capsule antigen (F1RDT) by sampling sputum or bubo aspirate was released. Results show rapid diagnostic F1RDT test can be used for people who have suspected pneumonic and bubonic plague but cannot be used in asymptomatic people. F1RDT may be useful in providing a fast result for prompt treatment and fast public health response as studies suggest that F1RDT
2415-487: A tumour of the breast may result in swelling of the lymph nodes under the arms and weight loss and night sweats may suggest a malignancy such as lymphoma. In addition to a medical exam by a medical practitioner , medical tests may include blood tests and scans may be needed to further examine the cause. A biopsy of a lymph node may also be needed. Lymph nodes can be affected by both primary cancers of lymph tissue, and secondary cancers affecting other parts of
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#17327653750802530-605: A vector to jump from animals to humans. The mortality rate is highest in the summer and early fall. The successful control of rat populations in dense urban areas is essential to outbreak prevention. One example is the use of a machine called the Sulfurozador , used to deliver sulphur dioxide to eradicate the pest that spread the bubonic plague in Buenos Aires, Argentina during the early 18th century. Targeted chemoprophylaxis , sanitation , and vector control also played
2645-517: Is another symptom. Occasionally, swollen lymph nodes, known as " buboes ", may break open. The three types of plague are the result of the route of infection: bubonic plague, septicemic plague , and pneumonic plague . Bubonic plague is mainly spread by infected fleas from small animals . It may also result from exposure to the body fluids from a dead plague-infected animal. Mammals such as rabbits , hares , and some cat species are susceptible to bubonic plague, and typically die upon contraction. In
2760-403: Is bubonic plague, followed by septicemic and pneumonic plague. Other clinical manifestations include plague meningitis, plague pharyngitis, and ocular plague. General symptoms of plague include fever, chills, headaches, and nausea. Many people experience swelling in their lymph nodes if they have bubonic plague. For those with pneumonic plague, symptoms may (or may not) include a cough, pain in
2875-508: Is called a germinal centre . The deeper paracortex mainly consists of the T cells . Here the T-cells mainly interact with dendritic cells , and the reticular network is dense. The medulla contains large blood vessels, sinuses and medullary cords that contain antibody-secreting plasma cells. There are fewer cells in the medulla. The medullary cords are cords of lymphatic tissue, and include plasma cells , macrophages, and B cells. In
2990-630: Is criss-crossed by the pseudopods of macrophages, which act to trap foreign particles and filter the lymph. The medullary sinuses converge at the hilum and lymph then leaves the lymph node via the efferent lymphatic vessel towards either a more central lymph node or ultimately for drainage into a central venous subclavian blood vessel . Lymph node enlargement or swelling is known as lymphadenopathy . Swelling may be due to many causes, including infections , tumors , autoimmune disease , drug reactions , diseases such as amyloidosis and sarcoidosis , or because of lymphoma or leukemia . Depending on
3105-523: Is highly sensitive for both pneumonic and bubonic plague. However, when using the rapid test, both positive and negative results need to be confirmed to establish or reject the diagnosis of a confirmed case of plague and the test result needs to be interpreted within the epidemiological context as study findings indicate that although 40 out of 40 people who had the plague in a population of 1000 were correctly diagnosed, 317 people were diagnosed falsely as positive. Bacteriologist Waldemar Haffkine developed
3220-410: Is known to cause beta-adrenergic blockade . Y. pestis spreads through the lymphatic vessels of the infected human until it reaches a lymph node , where it causes acute lymphadenitis . The swollen lymph nodes form the characteristic buboes associated with the disease, and autopsies of these buboes have revealed them to be mostly hemorrhagic or necrotic . If the lymph node is overwhelmed,
3335-621: Is made up of an outer cortex and an inner medulla. Lymph nodes become inflamed or enlarged in various diseases, which may range from trivial throat infections to life-threatening cancers . The condition of lymph nodes is very important in cancer staging , which decides the treatment to be used and determines the prognosis . Lymphadenopathy refers to glands that are enlarged or swollen. When inflamed or enlarged, lymph nodes can be firm or tender. Lymph nodes are kidney or oval shaped and range in size from 2 mm to 25 mm on their long axis, with an average of 15 mm. Each lymph node
3450-414: Is not considered necessary as long as standard and droplet precautions can be maintained. In cases of surgical mask shortages, patient overcrowding, poor ventilation in hospital wards, or other crises, pre-exposure prophylaxis might be warranted if sufficient supplies of antimicrobials are available. Postexposure prophylaxis should be considered for people who had close (<6 feet), sustained contact with
3565-479: Is not possible (such as some disaster areas). A systematic review by the Cochrane Collaboration found no studies of sufficient quality to make any statement on the efficacy of the vaccine. Diagnosing plague early leads to a decrease in transmission or spread of the disease. Pre-exposure prophylaxis for first responders and health care providers who will care for patients with pneumonic plague
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3680-420: Is one or more infected, enlarged, and painful lymph nodes, known as buboes . Buboes associated with the bubonic plague are commonly found in the armpits, upper femoral area, groin, and neck region. These buboes will grow and become more painful over time, often to the point of bursting. Symptoms include heavy breathing, continuous vomiting of blood ( hematemesis ), aching limbs, coughing, and extreme pain caused by
3795-457: Is possible by any of the following means: Yersinia pestis circulates in animal reservoirs, particularly in rodents, in the natural foci of infection found on all continents except Australia. The natural foci of plague are situated in a broad belt in the tropical and sub-tropical latitudes and the warmer parts of the temperate latitudes around the globe, between the parallels 55° N and 40° S. Contrary to popular belief, rats did not directly start
3910-651: Is recorded to have died of such contamination while engaging in warfare against the Xiongnu. Plague victims were also reported to have been tossed by catapult into cities under siege. In 1347, the Genoese possession of Caffa , a great trade emporium on the Crimean peninsula , came under siege by an army of Mongol warriors of the Golden Horde under the command of Jani Beg . After a protracted siege during which
4025-410: Is required. Y. pestis can be identified through both a microscope and by culturing a sample and this is used as a reference standard to confirm that a person has a case of plague. The sample can be obtained from the blood, mucus ( sputum ), or aspirate extracted from inflamed lymph nodes ( buboes ). If a person is administered antibiotics before a sample is taken or if there is a delay in transporting
4140-468: Is short, usually two to four days, but sometimes just a few hours. The initial signs are indistinguishable from several other respiratory illnesses; they include headache, weakness, and spitting or vomiting of blood. The course of the disease is rapid; unless diagnosed and treated soon enough, typically within a few hours, death may follow in one to six days; in untreated cases, mortality is nearly 100%. Transmission of Y. pestis to an uninfected individual
4255-464: Is surrounded by a fibrous capsule, which extends inside a lymph node to form trabeculae . The substance of a lymph node is divided into the outer cortex and the inner medulla . These are rich with cells. The hilum is an indent on the concave surface of the lymph node where lymphatic vessels leave and blood vessels enter and leave. Lymph enters the convex side of a lymph node through multiple afferent lymphatic vessels and from there flows into
4370-753: The Democratic Republic of the Congo , Madagascar and Peru . In the United States, infections occasionally occur in rural areas, where the bacteria are believed to circulate among rodents . It has historically occurred in large outbreaks , with the best known being the Black Death in the 14th century, which resulted in more than 50 million deaths in Europe. There are several different clinical manifestations of plague. The most common form
4485-470: The Democratic Republic of the Congo , Madagascar and Peru . It has historically occurred in large outbreaks , with the best known being the Black Death in the 14th century which resulted in more than 50 million dead. In recent years, cases have been distributed between small seasonal outbreaks which occur primarily in Madagascar, and sporadic outbreaks or isolated cases in endemic areas. In 2022
4600-506: The Great Plague of London in 1665–66. Later works, such as Albert Camus 's novel The Plague or Ingmar Bergman 's film The Seventh Seal have used bubonic plague in settings, such as quarantined cities in either medieval or modern times, as a backdrop to explore themes including the breakdown of society, institutions, and individuals during the plague; the cultural and psychological existential confrontation with mortality; and
4715-532: The Tokyo tribunal by Douglas MacArthur but 12 of them were prosecuted in the Khabarovsk War Crime Trials in 1949 during which some admitted having spread bubonic plague within a 36-kilometre (22 mi) radius around the city of Changde . Ishii innovated bombs containing live mice and fleas, with very small explosive loads, to deliver the weaponized microbes, overcoming the problem of
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4830-548: The Western canon . The Decameron , by Boccaccio, is notable for its use of a frame story involving individuals who have fled Florence for a secluded villa to escape the Black Death. First-person, sometimes sensationalized or fictionalized, accounts of living through plague years have also been popular across centuries and cultures. For example, Samuel Pepys 's diary makes several references to his first-hand experiences of
4945-484: The World Health Organization recommends that only high-risk groups, such as certain laboratory personnel and health care workers, get inoculated. Several antibiotics are effective for treatment, including streptomycin , gentamicin , and doxycycline . Without treatment, plague results in the death of 30% to 90% of those infected. Death, if it occurs, is typically within 10 days. With treatment,
5060-616: The Yunnan Province in 1855. The term bubonic is derived from the Greek word βουβών , meaning ' groin ' . The bubonic plague is an infection of the lymphatic system , usually resulting from the bite of an infected flea, Xenopsylla cheopis (the Oriental rat flea ). Several flea species carried the bubonic plague, such as Pulex irritans (the human flea ), Xenopsylla cheopis , and Ceratophyllus fasciatus . Xenopsylla cheopis
5175-441: The bacterium Yersinia pestis . Symptoms include fever , weakness and headache . Usually this begins one to seven days after exposure. There are three forms of plague, each affecting a different part of the body and causing associated symptoms. Pneumonic plague infects the lungs, causing shortness of breath, coughing and chest pain; bubonic plague affects the lymph nodes , making them swell; and septicemic plague infects
5290-515: The besiegers and from them penetrated the town. The Mongol forces catapulted plague-infested corpses into Caffa as a form of attack, one of the first known instances of biological warfare . When spring arrived, the Italian merchants fled on their ships, unknowingly carrying the Black Death. Carried by the fleas on rats, the plague initially spread to humans near the Black Sea and then outwards to
5405-469: The deep cervical lymph nodes . However, the CNS does innervate lymph node by sympathetic nerves . These regulate lymphocyte proliferation and migration , antibody secretion , blood perfusion , and inflammatory cytokine production . A lymph node is divided into compartments called nodules (or lobules), each consisting of a region of cortex with combined follicle B cells, a paracortex of T cells, and
5520-514: The fluoroquinolone ciprofloxacin . Mortality associated with treated cases of bubonic plague is about 1–15%, compared to a mortality of 40–60% in untreated cases. People potentially infected with the plague need immediate treatment and should be given antibiotics within 24 hours of the first symptoms to prevent death. Other treatments include oxygen, intravenous fluids, and respiratory support. People who have had contact with anyone infected by pneumonic plague are given prophylactic antibiotics. Using
5635-433: The high endothelial venules and provides the growth and regulatory factors necessary for activation and maturation of immune cells. Lymph enters the convex side of a lymph node through multiple afferent lymphatic vessels, which form a network of lymphatic vessels ( Latin : plexus ) and flows into a space ( Latin : sinus ) underneath the capsule called the subcapsular sinus. From here, lymph flows into sinuses within
5750-550: The 18th century. The disease remained localized in Southwest China for several years before spreading. In the city of Canton , beginning in January 1894, the disease had killed 80,000 people by June. Daily water traffic with the nearby city of Hong Kong rapidly spread the plague there, killing over 2,400 within two months during the 1894 Hong Kong plague . The third pandemic spread the disease to port cities throughout
5865-466: The 8th century. Because the infectious disease spread inland by the transferring of merchandise through Justinian's efforts in acquiring luxurious goods of the time and exporting supplies, his capital became the leading exporter of the bubonic plague. Procopius, in his work Secret History , declared that Justinian was a demon of an emperor who either created the plague himself or was being punished for his sinfulness. Medieval society's increasing population
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#17327653750805980-590: The Centers for Disease Control and Prevention in 2021. The plague bacterium could develop drug resistance and again become a major health threat. One case of a drug-resistant form of the bacterium was found in Madagascar in 1995. Further outbreaks in Madagascar were reported in November 2014 and October 2017. Globally about 600 cases are reported a year. In 2017, the countries with the most cases include
6095-581: The Democratic Republic of the Congo had the most plague cases, with over 1,100 cases in the Democratic Republic of the Congo alone. From 1,000 to 2,000 cases are conservatively reported per year to the WHO . From 2012 to 2017, reflecting political unrest and poor hygienic conditions, Madagascar began to host regular epidemics. Between 1900 and 2015, the United States had 1,036 human plague cases, with an average of 9 cases per year. In 2015, 16 people in
6210-683: The European population. Because the plague killed so many of the working population, wages rose due to the demand for labor. Some historians see this as a turning point in European economic development . The disease is also considered to have been responsible for the Plague of Justinian , originating in the Eastern Roman Empire in the 6th century CE, as well as the third epidemic , affecting China , Mongolia , and India , originating in
6325-543: The Mongol army was reportedly withering from the disease, they decided to use the infected corpses as a biological weapon. The corpses were catapulted over the city walls, infecting the inhabitants. This event might have led to the transfer of the Black Death via their ships into the south of Europe , possibly explaining its rapid spread. During World War II , the Japanese Army developed weaponized plague, based on
6440-584: The Wars , of his personal encounter with the plague and the effect it had on the rising empire. In the spring of 542, the plague arrived in Constantinople, working its way from port city to port city and spreading around the Mediterranean Sea , later migrating inland eastward into Asia Minor and west into Greece and Italy. The Plague of Justinian is said to have been "completed" in the middle of
6555-441: The afferent lymph vessel and also with that of the similar sinuses flanking the trabeculae and within the cortex. These vessels are smaller and do not allow the passage of macrophages so that they remain contained to function within a lymph node. In the course of the lymph, lymphocytes may be activated as part of the adaptive immune response . There is usually only one efferent vessel though sometimes there may be two, in contrast to
6670-400: The antigen and present it to follicular helper T cells on the B and T cell zone interface. If a cognate FTh cell is found it will upregulate CD40L and promote somatic hypermutation and isotype class switching of the B cell, increasing its antigen binding affinity and changing its effector function. Proliferation of cells within a lymph node will make the node expand. Lymph is present throughout
6785-658: The bacterium reproduces in the person's blood and lungs respectively. Laboratory testing is required in order to diagnose and confirm plague. Ideally, confirmation is through the identification of Y. pestis culture from a patient sample. Confirmation of infection can be done by examining serum taken during the early and late stages of infection . To quickly screen for the Y. pestis antigen in patients, rapid dipstick tests have been developed for field use. Samples taken for testing include: Bubonic plague outbreaks are controlled by pest control and modern sanitation techniques. This disease uses fleas commonly found on rats as
6900-535: The bacterium, developing strains resistant to antibiotics, combining the bacterium with other diseases (such as diphtheria ), and genetic engineering. Scientists who worked in USSR bio-weapons programs have stated that the Soviet effort was formidable and that large stocks of weaponised plague bacteria were produced. Information on many of the Soviet and US projects is largely unavailable. Aerosolized pneumonic plague remains
7015-423: The blood and can cause tissues to turn black and die . The bubonic and septicemic forms are generally spread by flea bites or handling an infected animal, whereas pneumonic plague is generally spread between people through the air via infectious droplets. Diagnosis is typically by finding the bacterium in fluid from a lymph node, blood or sputum . Those at high risk may be vaccinated . Those exposed to
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#17327653750807130-399: The body - such as the paraaortic lymph nodes and the tracheobronchial lymph nodes . The lymphatic drainage patterns are different from person to person and even asymmetrical on each side of the same body. There are no lymph nodes in the central nervous system , which is separated from the body by the blood–brain barrier . Lymph from the meningeal lymphatic vessels in the CNS drains to
7245-412: The body and possibly ischemic necrosis (tissue death due to lack of circulation/perfusion to that tissue) from the clots. DIC results in depletion of the body's clotting resources so that it can no longer control bleeding. Consequently, there is bleeding into the skin and other organs, which can cause red and/or black patchy rash and hemoptysis/hematemesis (coughing up/ vomiting of blood). There are bumps on
7360-411: The body by the lymphatic vessels . They are major sites of lymphocytes that include B and T cells . Lymph nodes are important for the proper functioning of the immune system , acting as filters for foreign particles including cancer cells , but have no detoxification function. In the lymphatic system, a lymph node is a secondary lymphoid organ . A lymph node is enclosed in a fibrous capsule and
7475-512: The body called antigen-presenting cells , such as dendritic cells. These antigen presenting cells enter the lymph system and then lymph nodes. They present the antigen to T cells and, if there is a T cell with the appropriate T cell receptor, it will be activated. B cells acquire antigen directly from the afferent lymph. If a B cell binds its cognate antigen it will be activated. Some B cells will immediately develop into antibody secreting plasma cells, and secrete IgM. Other B cells will internalize
7590-423: The body can cause lymph nodes to enlarge because of tumorous cells that have metastasised into the node. Lymph node involvement is often a key part in the diagnosis and treatment of cancer, acting as " sentinels " of local disease, incorporated into TNM staging and other cancer staging systems. As part of the investigations or workup for cancer, lymph nodes may be imaged or even surgically removed. If removed,
7705-403: The body, and circulates through lymphatic vessels . These drain into and from lymph nodes – afferent vessels drain into nodes, and efferent vessels from nodes. When lymph fluid enters a node, it drains into the node just beneath the capsule in a space called the subcapsular sinus. The subcapsular sinus drains into trabecular sinuses and finally into medullary sinuses. The sinus space
7820-435: The body, are more concentrated near and within the trunk, and are divided into groups. There are about 450 lymph nodes in the adult. Some lymph nodes can be felt when enlarged (and occasionally when not), such as the axillary lymph nodes under the arm, the cervical lymph nodes of the head and neck and the inguinal lymph nodes near the groin crease. Most lymph nodes lie within the trunk adjacent to other major structures in
7935-462: The body. Primary cancers of lymph tissue are called lymphomas and include Hodgkin lymphoma and non-Hodgkin lymphoma . Cancer of lymph nodes can cause a wide range of symptoms from painless long-term slowly growing swelling to sudden, rapid enlargement over days or weeks, with symptoms depending on the grade of the tumour. Most lymphomas are tumours of B-cells. Lymphoma is managed by haematologists and oncologists . Local cancer in many parts of
8050-470: The breeding and release of large numbers of fleas. During the Japanese occupation of Manchuria , Unit 731 deliberately infected Chinese , Korean and Manchurian civilians and prisoners of war with the plague bacterium. These subjects, termed "maruta" or "logs", were then studied by dissection , others by vivisection while still conscious. Members of the unit such as Shiro Ishii were exonerated from
8165-435: The broad-based antibiotic streptomycin has proven to be dramatically successful against the bubonic plague within 12 hours of infection. Globally between 2010 and 2015, there were 3,248 documented cases, which resulted in 584 deaths. The countries with the greatest number of cases are the Democratic Republic of the Congo , Madagascar , and Peru . For over a decade since 2001, Zambia, India, Malawi, Algeria, China, Peru, and
8280-426: The bubonic form of plague, the bacteria enter through the skin through a flea bite and travel via the lymphatic vessels to a lymph node , causing it to swell. Diagnosis is made by finding the bacteria in the blood, sputum , or fluid from lymph nodes. Prevention is through public health measures such as not handling dead animals in areas where plague is common. While vaccines against the plague have been developed,
8395-416: The cause, swelling may be painful, particularly if the expansion is rapid and due to an infection or inflammation. Lymph node enlargement may be localized to an area, which might suggest a local source of infection or a tumour in that area that has spread to the lymph node. It may also be generalized, which might suggest infection, connective tissue or autoimmune disease, or a malignancy of blood cells such as
8510-410: The chest, and haemoptysis. When a flea bites a human and contaminates the wound with regurgitated blood, the plague-causing bacteria are passed into the tissue. Y. pestis can reproduce inside cells, so even if phagocytosed , they can still survive. Once in the body, the bacteria can enter the lymphatic system , which drains interstitial fluid . Plague bacteria secrete several toxins , one of which
8625-484: The clinical guidelines on treatment and prophylaxis of plague published in 2021. If diagnosed in time, the various forms of plague are usually highly responsive to antibiotic therapy. The antibiotics often used are streptomycin , chloramphenicol and tetracycline . Amongst the newer generation of antibiotics, gentamicin and doxycycline have proven effective in monotherapeutic treatment of plague. Guidelines on treatment and prophylaxis of plague were published by
8740-418: The cortex. After passing through the cortex, lymph then collects in medullary sinuses. All of these sinuses drain into the efferent lymphatic vessels to exit the node at the hilum on the concave side. These are channels within the node lined by endothelial cells along with fibroblastic reticular cells, allowing for the smooth flow of lymph. The endothelium of the subcapsular sinus is continuous with that of
8855-592: The country. Unusually, most of the cases were pneumonic rather than bubonic. In June 2018, a child was confirmed to be the first person in Idaho to be infected by bubonic plague in nearly 30 years. A couple died in May 2019, in Mongolia, while hunting marmots . Another two people in the province of Inner Mongolia, China, were treated in November 2019 for the disease. In July 2020, in Bayannur , Inner Mongolia of China,
8970-510: The death of tissue. Y. pestis bacilli can resist phagocytosis and even reproduce inside phagocytes and kill them. As the disease progresses, the lymph nodes can hemorrhage and become swollen and necrotic . Bubonic plague can progress to lethal septicemic plague in some cases. The plague is also known to spread to the lungs and become the disease known as the pneumonic plague . Symptoms appear two to seven days after getting bitten and they include: The best-known symptom of bubonic plague
9085-435: The decay or decomposition of the skin while the person is still alive. Additional symptoms include extreme fatigue, gastrointestinal problems, spleen inflammation, lenticulae (black dots scattered throughout the body), delirium, coma , organ failure, and death. Organ failure is a result of the bacteria infecting organs through the bloodstream. Other forms of the disease include septicemic plague and pneumonic plague , in which
9200-515: The explosive killing the infected animal and insect by the use of a ceramic, rather than metal, casing for the warhead. While no records survive of the actual usage of the ceramic shells, prototypes exist and are believed to have been used in experiments during WWII. After World War II, both the United States and the Soviet Union developed means of weaponising pneumonic plague. Experiments included various delivery methods, vacuum drying, sizing
9315-638: The first plague vaccine in 1897. He conducted a massive inoculation program in British India , and it is estimated that 26 million doses of Haffkine's anti-plague vaccine were sent out from Bombay between 1897 and 1925, reducing the plague mortality by 50–85%. Since human plague is rare in most parts of the world as of 2023, routine vaccination is not needed other than for those at particularly high risk of exposure, nor for people living in areas with enzootic plague, meaning it occurs at regular, predictable rates in populations and specific areas, such as
9430-463: The flea, sticking together to form a plug that blocks its stomach and causes it to starve. The flea then bites a host and continues to feed, even though it cannot quell its hunger, and consequently, the flea vomits blood tainted with the bacteria back into the bite wound. The bubonic plague bacterium then infects a new person and the flea eventually dies from starvation. Serious outbreaks of plague are usually started by other disease outbreaks in rodents or
9545-410: The gut of infected fleas, and this results in the flea regurgitating ingested blood, which is now infected, into the bite site of a rodent or human host. Once established, the bacteria rapidly spread to the lymph nodes of the host and multiply. The fleas that transmit the disease only directly infect humans when the rat population in the area is wiped out from a mass infection. Furthermore, in areas with
9660-422: The infection can pass into the bloodstream, causing secondary septicemic plague and if the lungs are seeded, it can cause secondary pneumonic plague . Lymphatics ultimately drain into the bloodstream, so the plague bacteria may enter the blood and travel to almost any part of the body. In septicemic plague, bacterial endotoxins cause disseminated intravascular coagulation (DIC), causing tiny clots throughout
9775-531: The latter's description was imprecise and also expressed doubts of its relation to the disease, and thus the bacterium is today only named after Yersin. The scale of death and social upheaval associated with plague outbreaks has made the topic prominent in many historical and fictional accounts since the disease was first recognized. The Black Death in particular is described and referenced in numerous contemporary sources , some of which, including works by Chaucer , Boccaccio , and Petrarch , are considered part of
9890-407: The lymph node that functions as a molecular sieve, to prevent pathogens that enter the lymph node through afferent vessels re-enter the blood stream. The lymph node capsule is composed of dense irregular connective tissue with some plain collagenous fibers , and a number of membranous processes or trabeculae extend from its internal surface. The trabeculae pass inward, radiating toward the center of
10005-417: The lymph node will be stained and examined under a microscope by a pathologist to determine if there is evidence of cells that appear cancerous (i.e. have metastasized into the node). The staging of the cancer, and therefore the treatment approach and prognosis, is predicated on the presence of node metastases. Lymphedema is the condition of swelling ( edema ) of tissue relating to insufficient clearance by
10120-413: The lymphatic system a lymph node is a secondary lymphoid organ . Lymph nodes contain lymphocytes , a type of white blood cell , and are primarily made up of B cells and T cells . B cells are mainly found in the outer cortex where they are clustered together as follicular B cells in lymphoid follicles, and T cells and dendritic cells are mainly found in the paracortex . There are fewer cells in
10235-489: The lymphatic system. It can be congenital as a result usually of undeveloped or absent lymph nodes, and is known as primary lymphedema. Lymphedema most commonly arises in the arms or legs, but can also occur in the chest wall, genitals, neck, and abdomen. Secondary lymphedema usually results from the removal of lymph nodes during breast cancer surgery or from other damaging treatments such as radiation . It can also be caused by some parasitic infections. Affected tissues are at
10350-573: The mass mortality rate cheapened life and thus increased warfare, crime, popular revolt, waves of flagellants , and persecution. The Black Death originated in Central Asia and spread from Italy and then throughout other European countries. Arab historians Ibn Al-Wardni and Almaqrizi believed the Black Death originated in Mongolia. Chinese records also show a huge outbreak in Mongolia in the early 1330s. In 2022, researchers presented evidence that
10465-480: The medulla than the cortex. The medulla contains plasma cells, as well as macrophages which are present within the medullary sinuses. As part of the reticular network, there are follicular dendritic cells in the B cell follicle and fibroblastic reticular cells in the T cell cortex. The reticular network provides structural support and a surface for adhesion of the dendritic cells, macrophages and lymphocytes. It also allows exchange of material with blood through
10580-420: The most significant threat. The plague can be easily treated with antibiotics. Some countries, such as the United States, have large supplies on hand if such an attack should occur, making the threat less severe. Lymph node A lymph node , or lymph gland , is a kidney -shaped organ of the lymphatic system and the adaptive immune system . A large number of lymph nodes are linked throughout
10695-472: The multiple afferent channels that bring lymph into the node. Medullary sinuses contain histiocytes (immobile macrophages) and reticular cells, the former of which, along with T and B cells, become activated in the presence of antigens through lymphatic flow. The fewer efferent vessels allow this flow to be slowed, providing time to activate and distribute a larger number of immune cells in the event of an infection. A lymph node contains lymphoid tissue, i.e.,
10810-409: The node, for about one-third or one-fourth of the space between the circumference and the center of the node. In some animals they are sufficiently well-marked to divide the peripheral or cortical portion of the node into a number of compartments (nodules), but in humans this arrangement is not obvious. The larger trabeculae springing from the capsule break up into finer bands, and these interlace to form
10925-547: The origin of the plague and how it traveled through the continent. Mitochondrial DNA of modern rats in Western Europe indicated that these rats came from two different areas, one being Africa and the other unclear. The research regarding this pandemic has greatly increased with technology. Through archaeo-molecular investigation, researchers have discovered the DNA of plague bacillus in the dental core of those that fell ill to
11040-436: The person's sample to a laboratory and/or a poorly stored sample, there is a possibility for false negative results. Polymerase chain reaction (PCR) may also be used to diagnose plague, by detecting the presence of bacterial genes such as the pla gene (plasmogen activator) and caf1 gene, (F1 capsule antigen). PCR testing requires a very small sample and is effective for both alive and dead bacteria. For this reason, if
11155-404: The plague as an allegory raising contemporary moral or spiritual questions. Some of the earliest instances of biological warfare were said to have been products of the plague, as armies of the 14th century were recorded catapulting diseased corpses over the walls of towns and villages to spread the pestilence. This was done by Jani Beg when he attacked the city of Kaffa in 1343. Later, plague
11270-613: The plague originated near Lake Issyk-Kul in Kyrgyzstan . The Mongols had cut the trade route (the Silk Road ) between China and Europe, which halted the spread of the Black Death from eastern Russia to Western Europe. The European epidemic may have begun with the siege of Caffa , an attack that Mongols launched on the Italian merchants' last trading station in the region, Caffa , in the Crimea . In late 1346, plague broke out among
11385-707: The plague was responsible for the Neolithic decline . The first recorded epidemic affected the Sasanian Empire and their arch-rivals, the Eastern Roman Empire (Byzantine Empire) and was named the Plague of Justinian (541–549 AD) after emperor Justinian I , who was infected but survived through extensive treatment. The pandemic resulted in the deaths of an estimated 25 million (6th century outbreak) to 50 million people (two centuries of recurrence). The historian Procopius wrote, in Volume II of History of
11500-482: The plague. Analysis of teeth of the deceased allows researchers to further understand both the demographics and mortuary patterns of the disease. For example, in 2013 in England, archeologists uncovered a burial mound to reveal 17 bodies, mainly children, who had died of the Bubonic plague. They analyzed these burial remains using radiocarbon dating to determine they were from the 1530s, and dental core analysis revealed
11615-574: The possible origin of all modern strands of Yersinia pestis DNA was found in human remains in three graves located in Kyrgyzstan , dated to 1338 and 1339. The siege of Caffa in Crimea in 1346, is known to have been the first plague outbreak with following strands, later to spread over Europe. Sequencing DNA compared to other ancient and modern strands paints a family tree of the bacteria. Bacteria today affecting marmots in Kyrgyzstan, are closest to
11730-512: The presence of Yersinia pestis. Other evidence for rats that are currently still being researched consists of gnaw marks on bones, predator pellets and rat remains that were preserved in situ . This research allows individuals to trace early rat remains to track the path traveled and in turn connect the impact of the Bubonic Plague to specific breeds of rats. Burial sites, known as plague pits, offer archaeologists an opportunity to study
11845-401: The remains of people who died from the plague. Another research study indicates that these separate pandemics were all interconnected. A current computer model indicates that the disease did not go away in between these pandemics. It rather lurked within the rat population for years without causing human epidemics. Plague (disease) Plague is an infectious disease caused by
11960-479: The rest of Europe as a result of people fleeing from one area to another. Rats migrated with humans, traveling among grain bags, clothing, ships, wagons, and grain husks. Continued research indicates that black rats , those that primarily transmitted the disease, prefer grain as a primary meal. Due to this, the major bulk grain fleets that transported major city's food shipments from Africa and Alexandria to heavily populated areas, and were then unloaded by hand, played
12075-450: The risk of death is around 10%. Globally between 2010 and 2015 there were 3,248 documented cases, which resulted in 584 deaths. The countries with the greatest number of cases are the Democratic Republic of the Congo , Madagascar , and Peru . The plague is considered the likely cause of the Black Death that swept through Asia, Europe, and Africa in the 14th century and killed an estimated 50 million people, including about 25% to 60% of
12190-506: The skin that look somewhat like insect bites; these are usually red, and sometimes white in the centre. Untreated, the septicemic plague is usually fatal. Early treatment with antibiotics reduces the mortality rate to between 4 and 15 per cent. The pneumonic form of plague arises from infection of the lungs . It causes coughing and thereby produces airborne droplets that contain bacterial cells and are likely to infect anyone inhaling them. The incubation period for pneumonic plague
12305-400: The spread of the bubonic plague. It is mainly a disease in the fleas ( Xenopsylla cheopis ) that infested the rats, making the rats themselves the first victims of the plague. Rodent-borne infection in a human occurs when a person is bitten by a flea that has been infected by biting a rodent that itself has been infected by the bite of a flea carrying the disease. The bacteria multiply inside
12420-517: The strand found in the graves, suggesting this is also the location where plague transferred from animals to humans. The plague has a long history as a biological weapon . Historical accounts from ancient China and medieval Europe details the use of infected animal carcasses, such as cows or horses, and human carcasses, by the Xiongnu / Huns , Mongols , Turks and other groups, to contaminate enemy water supplies. Han dynasty general Huo Qubing
12535-604: The western United States developed plague, including 2 cases in Yosemite National Park . These US cases usually occur in rural northern New Mexico, northern Arizona, southern Colorado, California, southern Oregon, and far western Nevada. In November 2017, the Madagascar Ministry of Health reported an outbreak to the WHO (World Health Organization) with more cases and deaths than any recent outbreak in
12650-524: The western United States. It is not even indicated for most travellers to countries with known recent reported cases, particularly if their travel is limited to urban areas with modern hotels. The United States CDC thus only recommends vaccination for (1) all laboratory and field personnel who are working with Y. pestis organisms resistant to antimicrobials: (2) people engaged in aerosol experiments with Y. pestis ; and (3) people engaged in field operations in areas with enzootic plague where preventing exposure
12765-685: The world in the second half of the 19th century and the early 20th century via shipping routes. The plague infected people in Chinatown in San Francisco from 1900 to 1904, and in the nearby locales of Oakland and the East Bay again from 1907 to 1909. During the former outbreak, in 1902, authorities made permanent the Chinese Exclusion Act , a law originally signed into existence by President Chester A. Arthur in 1882. The Act
12880-569: Was put to deadly halt when, in the Late Middle Ages , Europe experienced the deadliest disease outbreak in history. They called it the Great Dying or The Great Pestilence, later coined The Black Death. Lasting in potency for roughly six years, 1346–1352, the Black Death claimed one-third of the European human population, with mortality rates as high as 70%–80%. Some historians believe that society subsequently became more violent as
12995-574: Was supposed to last for 10 years, but was renewed in 1892 with the Geary Act , then followed by the 1902 decision. The last major outbreak in the United States occurred in Los Angeles in 1924, though the disease is still present in wild rodents and can be passed to humans who come in contact with them. According to the World Health Organization , the pandemic was considered active until 1959, when worldwide casualties dropped to 200 per year. In 1994,
13110-399: Was the most effective flea species for transmission. The flea is parasitic on house and field rats and seeks out other prey when its rodent host dies. Rats were an amplifying factor to bubonic plague due to their common association with humans as well as the nature of their blood. The rat's blood allows the rat to withstand a major concentration of the plague. The bacteria form aggregates in
13225-887: Was used during the Second Sino-Japanese War as a bacteriological weapon by the Imperial Japanese Army . These weapons were provided by Shirō Ishii 's units and used in experiments on humans before being used in the field. For example, in 1940, the Imperial Japanese Army Air Service bombed Ningbo with fleas carrying the bubonic plague. During the Khabarovsk War Crime Trials , the accused, such as Major General Kiyoshi Kawashima, testified that, in 1941, 40 members of Unit 731 air-dropped plague -contaminated fleas on Changde . These operations caused epidemic plague outbreaks. Substantial research has been done regarding
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