Plague ( disease ) - wikipedia Plague ( disease ) This article is about the disease caused by Yersinia pestis. For other uses, see Plague. Plague Yersinia pestis seen at 200 × magnification with a fluorescent label. Specialty Infectious disease Symptoms Fever, weakness, headache Usual onset 1 - 7 days after exposure Types Bubonic plague, septicemic plague, pneumonic plague Causes Yersinia pestis Diagnostic method Finding the bacterium in a lymph node, blood, sputum Prevention Plague vaccine Treatment Antibiotics and supportive care Medication Gentamicin and a fluoroquinolone Prognosis ~ 10 % risk of death ( with treatment ) Frequency ~ 600 cases a year ( edit on Wikidata ) Plague is an infectious disease caused by the bacterium Yersinia pestis. Symptoms include fever, weakness and headache. Usually this begins one to seven days after exposure. In the bubonic form there is also swelling of lymph nodes, while in the septicemic form tissues may turn black and die, and in the pneumonic form shortness of breath, cough and chest pain may occur. Bubonic and septicemic plague is generally spread by flea bites or handling an infected animal. The pneumonitic form 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 a case of pneumonic plague may be treated with preventative 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 the Democratic Republic of the Congo, Madagascar and Peru. In the United States infections usually occur in rural areas. It has historically occurred in large outbreaks, with the most well known being the Black Death in the 14th century, which resulted in greater than 50 million dead. Contents 1 Signs and symptoms 1.1 Bubonic plague 1.2 Septicemic plague 1.3 Pneumonic plague 2 Cause 3 Prevention 4 Treatments 5 Epidemiology 6 Biological weapon 7 References 8 External links Signs and Symptoms Bubonic plague Main article : Bubonic plague Swollen inguinal lymph glands on a person infected with the bubonic plague. The swollen lymph glands are termed buboes from the Greek word for groin, swollen gland : bubo. When a flea bites a human and contaminates the wound with regurgitated blood, the plague carrying 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 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, the infection can pass into the bloodstream, causing secondary septicemic plague and if the lungs are seeded, it can cause secondary pneumonic plague. Septicemic plague Main article : Septicemic plague Septicemic plague resulting in necrosis 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 the body and possibly ischaemic 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 the skin that look somewhat like insect bites ; these are usually red, and sometimes white in the center. Untreated, septicemic plague is usually fatal. Early treatment with antibiotics reduces the mortality rate to between 4 and 15 percent. People who die from this form of plague often die on the same day symptoms first appear. Pneumonic plague Main article : Pneumonic plague The pneumonic form of plague arises from infection of the lungs. It causes coughing and sneezing and thereby produces airborne droplets that contain bacterial cells and are likely to infect anyone inhaling them. The incubation period for pneumonic plague 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 %. Cause The Oriental rat flea ( Xenopsylla cheopsis ) engorged with blood after a blood meal. This species of flea is the primary vector for the transmission of Yersinia pestis, the organism responsible for bubonic plague in most plague epidemics in Asia, Africa and South America. Both male and female fleas feed on blood and can transmit the infection. A child bitten by a flea infected with the Yersinia pestis bacterium. Y. pestis, a member of the Enterobacteriaceae family, has caused the bite to become ulcerated. Transmission of Y. pestis to an uninfected individual is possible by any of the following means. droplet contact -- coughing or sneezing on another person direct physical contact -- touching an infected person, including sexual contact indirect contact -- usually by touching soil contamination or a contaminated surface airborne transmission -- if the microorganism can remain in the air for long periods fecal - oral transmission -- usually from contaminated food or water sources vector borne transmission -- carried by insects or other animals. 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 degrees North and 40 degrees South. Contrary to popular belief, rats did not directly start 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. 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 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 can not 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 a rise in the rodent population. Prevention Main article : Plague vaccine Since human plague is rare in most parts of the world, 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 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 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 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. Treatments 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. 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. Epidemiology Main article : Epidemiology of plague Distribution of plague infected animals 1998 Globally about 600 cases are reported a year. In 2017 the countries with the most cases include the Democratic Republic of the Congo, Madagascar and Peru. It has historically occurred in large outbreaks, with the most well known being the Black Death in the 14th century which resulted in greater than 50 million dead. Biological weapon Plague has a long history as a biological weapon. Historical accounts from ancient China and medieval Europe detail 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 is recorded to have died of such a 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 Janibeg. After a protracted siege during which 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. The Genoese traders fled, transferring the plague ( Black Death ) via their ships into the south of Europe, hence its rapid spread. During World War II, the Japanese Army developed weaponised plague, based on 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 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 - km 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 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 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 projects is largely unavailable. Aerosolized pneumonic plague remains the most significant threat. The plague can be easily treated with antibiotics, which some countries, such as the United States, have large supplies on hand if such an attack should occur, thus making the threat less severe. References ^ Jump up to : `` Symptoms Plague ''. CDC. September 2015. Retrieved 8 November 2017. ^ Jump up to : `` Plague ''. World Health Organization. October 2017. Retrieved 8 November 2017. ^ Jump up to : `` Resources for Clinicians Plague ''. CDC. October 2015. Retrieved 8 November 2017. ^ Jump up to : `` FAQ Plague ''. CDC. September 2015. Retrieved 8 November 2017. Jump up ^ `` Transmission Plague ''. CDC. September 2015. Retrieved 8 November 2017. Jump up ^ Brown, SD ; Montie, TC ( 1977 ). `` Beta - adrenergic blocking activity of Yersinia pestis murine toxin ''. Infection and Immunity. 18 ( 1 ) : 85 -- 93. PMC 421197. PMID 198377. Jump up ^ Sebbane, F ; Jarret, C.O. ; Gardner, D ; Long, D ; Hinnebusch, B.J. `` Role of Yersinia pestis plasminogen activator in the incidence of distinct septicemic and bubonic forms of flea - borne plague ''. Proc Natl Acad Sci USA. 103 ( 14 ) : 5526 -- 5530. doi : 10.1073 / pnas. 0509544103. Jump up ^ `` Symptoms Plague ''. Centers for Disease Control and Prevention. 14 September 2015. Retrieved 18 April 2017. Jump up ^ Sebbane, F ; Gardner, D ; Long, D ; Gowen, B.B. ; Hinnebusch, B.J. `` Kinetics of Disease Progression and Host Response in a Rat Model of Bubonic Plague ''. Am J Pathol. 166 ( 5 ) : 1427 -- 1439. doi : 10.1016 / S0002 - 9440 ( 10 ) 62360 - 7. Jump up ^ `` Plague ''. Centers for Disease Control and Prevention. Retrieved 2014 - 08 - 05. Jump up ^ Wagle PM ( 1948 ). `` Recent advances in the treatment of bubonic plague ''. Indian J Med Sci. 2 : 489 -- 94. Jump up ^ Meyer KF ( 1950 ). `` Modern therapy of plague ''. J Am Med Assoc. 144 ( 12 ) : 982 -- 85. doi : 10.1001 / jama. 1950.02920120006003. PMID 14774219. Jump up ^ Datt Gupta AK ( 1948 ). `` A short note on plague cases treated at Campbell Hospital ''. Ind Med Gaz. 83 : 150 -- 51. Jump up ^ Ryan, K.J. ; Ray, C.G., eds. ( 2004 ). Sherris Medical Microbiology : An Introduction to Infectious Diseases ( 4th ed. ). New York : McGraw - Hill. ISBN 0 - 8385 - 8529 - 9. Jump up ^ Hoffman SL ( 1980 ). `` Plague in the United States : the `` Black Death '' is still alive ``. Annals of Emergency Medicine. 9 ( 6 ) : 319 -- 22. doi : 10.1016 / S0196 - 0644 ( 80 ) 80068 - 0. PMID 7386958. ^ Jump up to : Plague Manual : Epidemiology, Distribution, Surveillance and Control, pp. 9, 11. WHO / CDS / CSR / EDC / 99.2 Jump up ^ Yersin, Alexandre ( 1894 ). `` La peste bubonique à Hong - Kong ''. Annales de l'Institut Pasteur. 8 : 662 -- 67. Jump up ^ `` Plague Vaccine ''. CDC. June 11, 1982. Retrieved Apr 30, 2015. Jump up ^ Jefferson T, Demicheli V, Pratt M ; Demicheli ; Pratt ( 2000 ). Jefferson, Tom, ed. `` Vaccines for preventing plague ''. Cochrane Database Syst Rev ( 2 ) : CD000976. doi : 10.1002 / 14651858. CD000976. PMID 10796565. CS1 maint : Multiple names : authors list ( link ) Jump up ^ Mwengee W ; Butler, Thomas ; Mgema, Samuel ; Mhina, George ; Almasi, Yusuf ; Bradley, Charles ; Formanik, James B. ; Rochester, C. George ( 2006 ). `` Treatment of Plague with Genamicin or Doxycycline in a Randomized Clinical Trial in Tanzania ''. Clin Infect Dis. 42 ( 5 ) : 614 -- 21. doi : 10.1086 / 500137. PMID 16447105. Jump up ^ Drug - resistant plague a ' major threat ', say scientists, SciDev.Net. Jump up ^ `` Plague -- Madagascar ''. World Health Organisation. 21 November 2014. Retrieved 26 November 2014. Jump up ^ `` WHO scales up response to plague in Madagascar ''. World Health Organization ( WHO ). 1 October 2017. Retrieved 5 October 2017. Jump up ^ Wheelis M. ( 2002 ). `` Biological warfare at the 1346 siege of Caffa ''. Emerg Infect Dis. Center for Disease Control. 8 ( 9 ) : 971 -- 75. doi : 10.3201 / eid0809. 010536. PMC 2732530. PMID 12194776. Jump up ^ Daniel Barenblatt, A plague upon Humanity, HarperCollns, 2004, pp. 220 -- 21 Jump up ^ Tamparo, Carol ; Lewis, Marcia ( 2011 ). Diseases of the Human Body. Philadelphia, PA : F.A. Davis Company. p. 70. ISBN 9780803625051. External links Classification V T D ICD - 10 : A20 ICD - 9 - CM : 020 DiseasesDB : 14226 External resources MedlinePlus : 000596 eMedicine : med / 3381 Patient UK : Plague ( disease ) Orphanet : 707 WHO Health topic CDC Plague map world distribution, publications, information on bioterrorism preparedness and response regarding plague Symptoms, causes, pictures of bubonic plague Infectious diseases Bacterial disease : Proteobacterial G − primarily A00 -- A79, 001 -- 041, 080 -- 109 α Rickettsiales Rickettsiaceae / ( Rickettsioses ) Typhus Rickettsia typhi Murine typhus Rickettsia prowazekii Epidemic typhus, Brill -- Zinsser disease, Flying squirrel typhus Spotted fever Tick - borne Rickettsia rickettsii Rocky Mountain spotted fever Rickettsia conorii Boutonneuse fever Rickettsia japonica Japanese spotted fever Rickettsia sibirica North Asian tick typhus Rickettsia australis Queensland tick typhus Rickettsia honei Flinders Island spotted fever Rickettsia africae African tick bite fever Rickettsia parkeri American tick bite fever Rickettsia aeschlimannii Rickettsia aeschlimannii infection Mite - borne Rickettsia akari Rickettsialpox Orientia tsutsugamushi Scrub typhus Flea - borne Rickettsia felis Flea - borne spotted fever Anaplasmataceae Ehrlichiosis : Anaplasma phagocytophilum Human granulocytic anaplasmosis, Anaplasmosis Ehrlichia chaffeensis Human monocytotropic ehrlichiosis Ehrlichia ewingii Ehrlichiosis ewingii infection Rhizobiales Brucellaceae Brucella abortus Brucellosis Bartonellaceae Bartonellosis : Bartonella henselae Cat - scratch disease Bartonella quintana Trench fever Either B. henselae or B. quintana Bacillary angiomatosis Bartonella bacilliformis Carrion 's disease, Verruga peruana β Neisseriales M+ Neisseria meningitidis / meningococcus Meningococcal disease, Waterhouse -- Friderichsen syndrome, Meningococcal septicaemia M − Neisseria gonorrhoeae / gonococcus Gonorrhea ungrouped : Eikenella corrodens / Kingella kingae HACEK Chromobacterium violaceum Chromobacteriosis infection Burkholderiales Burkholderia pseudomallei Melioidosis Burkholderia mallei Glanders Burkholderia cepacia complex Bordetella pertussis / Bordetella parapertussis Pertussis γ Enterobacteriales ( OX − ) Lac+ Klebsiella pneumoniae Rhinoscleroma, Klebsiella pneumonia Klebsiella granulomatis Granuloma inguinale Klebsiella oxytoca Escherichia coli : Enterotoxigenic Enteroinvasive Enterohemorrhagic O157 : H7 O104 : H4 Hemolytic - uremic syndrome Enterobacter aerogenes / Enterobacter cloacae Slow / weak Serratia marcescens Serratia infection Citrobacter koseri / Citrobacter freundii Lac − H2S+ Salmonella enterica Typhoid fever, Paratyphoid fever, Salmonellosis H2S − Shigella dysenteriae / sonnei / flexneri / boydii Shigellosis, Bacillary dysentery Proteus mirabilis / Proteus vulgaris Yersinia pestis Plague / Bubonic plague Yersinia enterocolitica Yersiniosis Yersinia pseudotuberculosis Far East scarlet - like fever Pasteurellales Haemophilus : H. influenzae Haemophilus meningitis Brazilian purpuric fever H. ducreyi Chancroid H. parainfluenzae HACEK Pasteurella multocida Pasteurellosis Actinobacillus Actinobacillosis Aggregatibacter actinomycetemcomitans HACEK Legionellales Legionella pneumophila / Legionella longbeachae Legionnaires ' disease Coxiella burnetii Q fever Thiotrichales Francisella tularensis Tularemia Vibrionaceae Vibrio cholerae Cholera Vibrio vulnificus Vibrio parahaemolyticus Vibrio alginolyticus Plesiomonas shigelloides Pseudomonadales Pseudomonas aeruginosa Pseudomonas infection Moraxella catarrhalis Acinetobacter baumannii Xanthomonadaceae Stenotrophomonas maltophilia Cardiobacteriaceae Cardiobacterium hominis HACEK Aeromonadales Aeromonas hydrophila / Aeromonas veronii Aeromonas infection ε Campylobacterales Campylobacter jejuni Campylobacteriosis, Guillain -- Barré syndrome Helicobacter pylori Peptic ulcer, MALT lymphoma, Gastric cancer Helicobacter cinaedi Helicobacter cellulitis GND : 4045326 - 1 NDL : 00569104 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Plague_(disease)&oldid=821594206 '' Categories : Deaths from plague ( disease ) Plague ( disease ) Bacterium - related cutaneous conditions Biological weapons Epidemics Insect - borne diseases Rodent - carried diseases Zoonoses Zoonotic bacterial diseases Cat diseases Hidden categories : CS1 maint : Multiple names : authors list Infobox medical condition ( new ) All articles with unsourced statements Articles with unsourced statements from January 2015 Articles with unsourced statements from May 2014 Wikipedia articles with GND identifiers RTT Talk Contents About Wikipedia Alemannisch Azərbaycanca تۆرکجه বাংলা Bahasa Banjar Bân - lâm - gú Беларуская Беларуская ( тарашкевіца ) ‎ Български Bosanski Brezhoneg Català Čeština Dansk Deutsch ދިވެހިބަސް Eesti Ελληνικά Emiliàn e rumagnòl Español Esperanto Euskara فارسی Français Frysk Galego ગુજરાતી 한국어 हिन्दी Hrvatski Ido Bahasa Indonesia Italiano עברית ಕನ್ನಡ ქართული Қазақша Kiswahili Кыргызча Latina Latviešu Lëtzebuergesch Lietuvių Magyar Македонски മലയാളം მარგალური မြန်မာဘာသာ Nederlands Nedersaksies नेपाली 日本 語 Nordfriisk Norsk Norsk nynorsk Occitan ਪੰਜਾਬੀ پښتو Polski Português Română Русский Shqip Sicilianu Slovenščina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska தமிழ் తెలుగు ไทย Türkçe Українська اردو Vahcuengh Vèneto Tiếng Việt West - 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Question: what was the vector of the bubonic plague
Answer: fleas