21st century Madagascar plague outbreaks

Last updated

Madagascar has experienced several outbreaks of bubonic and pneumonic plague in the 21st century. In the outbreak beginning in 2014, 71 died; [1] in 2017, 202 died. [2] Smaller outbreaks occurred in January 2008 (18 deaths), [3] and December 2013. [4] [5]

Contents

2014 Madagascar plague outbreak
Madagascar - Location Map (2013) - MDG - UNOCHA.svg
Date31 August 2014 (2014-08-31)– 11 February 2015 (2015-02-11)
Location Madagascar
Cause Bubonic and pneumonic plague
Outcome263 confirmed cases
Deaths71 (27% fatality rate)
as of 11 February 2015
2017 Madagascar plague outbreak
Madagascar - Location Map (2013) - MDG - UNOCHA.svg
Date27 August 2017 (2017-08-27) – early 2018
Location Madagascar
Cause Bubonic and pneumonic plague
Outcome2575 (suspected, probable, confirmed cases)
Deaths221 (8.6% case fatality rate)
as of 15 December 2017 [6]

History

2014

An outbreak of plague in Madagascar in 2014 started on 31 August. On that day the first case, a man from Soamahamanina village in Tsiroanomandidy, was identified. [7] The patient died on 3 September. [7] The outbreak was in the form of bubonic and pneumonic plague. By 16 November 2014, a total of 119 cases had been confirmed, including 40 deaths. [7] Two percent of reported cases were of the pneumonic form. By 21 November, in the capital Antananarivo there were two confirmed cases, including one death. [8]

On 4 November 2014, the Ministry of Health of Madagascar reported the outbreak to the World Health Organization. [7]

On 11 February 2015, the WHO and Madagascar Ministry of Health released a follow-up situation report the outbreak. [9] The report stated the outbreak beginning in September 2014 peaked from November through end-December and had slowed down as of February 2015. [9] The WHO report cited 263 cases and 71 deaths with a 27% fatality rate. [9] Efficient identification and treatment with antibiotics were noted as critical to treatment efficacy, evidenced by fatality rates ranging from 15% - 60% depending on early identification and treatment. [9] The report explained that Madagascar's plague "season" typically runs through April and stopped short of officially declaring the outbreak over.

2017

A more recent outbreak of plague in Madagascar began in August 2017 and expanded rapidly, with about two-thirds of cases transmitted person-to-person as pneumonic plague, the most dangerous form of the disease. [10] The death toll of 124 by 20 October exceeded that of previous outbreaks.[ citation needed ] More than half of cases have been recorded in the capital of Antananarivo and the main port of Toamasina, the largest cities in Madagascar. Nine nearby countries were considered at high risk of a similar outbreak. [11] The outbreak appeared to peak in mid-October with the number of new cases declining. [12] Typically the annual plague outbreak peaks in December and runs until April.

On 2 November, a ProMED-mail moderator expressed surprise at the considerable variation reported in numbers of cases and deaths, especially with the relatively low case-fatality rate considering that pneumonic plague is reported to account for over 60 percent of deaths. [13] An article from the World Health Organization reported more than 1800 cases as of late October, while nearly 500 fewer had been reported in the week previously. [14]

In January 2018 the experts declared the outbreak over as no new cases had been reported since November 2017, although the World health organization stated that there was a "moderate" chance of re-occurrence. Malagasy Prime Minister Olivier Mahafaly Solonandrasana had declared the crisis over on 23 November 2017. [15]

August

The outbreak began in August 2017 with the death from pneumonic plague of a 31-year-old man who had been traveling in a crowded minibus toward the capital city of Antananarivo in the central highlands. [16] The outbreak expanded rapidly, transmitted person-to-person in the pneumonic form of the disease, which accounted for more than 60 percent of cases. [17] Scientists discovered three new strains of Y. pestis in Madagascar in 2017. Additionally, one strain of Y. pestis was found to be resistant to antibiotic treatment. [18] Because of plague moving from rural to urban areas, there is increased risk of transmission to other countries. Urban areas that are major transportation hubs for shipping and recreation are at high risk for transmitting plague to nearby countries.

September–October

The outbreak was initially recognized on 11 September by local authorities and confirmed by the Institut Pasteur de Madagascar. Authorities called the outbreak "quite worrisome" because the number of cases per day was growing rapidly, and many cases were in urban areas where there are more opportunities for contact between people. [19] Panic was reported in the capital, with the main hospital overcrowded with cases. [20] The death toll in this outbreak had by mid-October exceeded an outbreak in 2014. Most cases were of the pneumonic form. The bubonic form, transmitted by the bites of fleas from rodents, is more usual in the annual outbreaks in Madagascar. The government announced they had "temporarily suspended gatherings to the general public in places where the traceability of the participants is difficult if not impossible (stadiums, sports palaces, gymnasiums …)". [21]

November

By 8 November, deaths had risen to 165 with infections totalling over 2000, however the rate of spread had slowed, raising hope that the outbreak was starting to come under control. Concerns continued to be raised that plague might still spread to neighboring countries, or mutate to a form that could be more difficult to treat. [22] By 15 November, there had been 171 deaths and 2119 total cases of plague, however no new infections had been reported since 28 October. [23]

Background

Plague is caused by the bacterium Yersinia pestis and is most commonly transmitted through infected fleas. [24] There are three types of plague: bubonic, pneumonic and septicemic. Bubonic plague is the most well-known type. This type of plague results in swollen lymph nodes that are called buboes. This type of plague is treatable with antibiotics, but if not treated effectively, the infection can spread to different parts of the body. Pneumonic plague occurs when plague infects the lungs and is transmissible person to person through infected droplets. This form of plague is very deadly. Septicemic plague occurs when plague enters the blood. Skin and tissues turn black and die, and bleeding into skin and organs often occurs. This form of plague is also deadly. Pneumonic plague and septicemic plague often occur when bubonic plague goes untreated and are difficult to diagnose. [25]

Endemic plague

Plague has endemically resided in Madagascar since it was first brought to the island from India in 1898, on the central high plateau of Madagascar, usually occurring every year as a seasonal upsurge during the rainy season. [26] Plague resides in Madagascar similar to the way flu resides in the United States. "Plague season" is generally October through March, and mostly affects rural areas of Madagascar. [25] Plague, although endemic, has been relatively dormant in Madagascar until 1990. Annually until then, there were about 20-30 cases reported a year. Recently, however, the annual number of cases has risen to typically between 800 and 1500 a year. [27] All cases of plague must be reported to the Ministry of Health; however, cases often go underreported due to lack of quality epidemiologic resources in rural areas. Tests for plague used in these areas often have low sensitivity and are unreliable. [28] In the past, cases of plague in Madagascar have been bubonic and not transmittable person to person. The increase in plague cases over the last 20 years have been largely due to an increase in pneumonic plague. [27] Pneumonic plague is transmitted person to person via infected droplets. It is often difficult to diagnose and by the time it is diagnosed, cases are usually fatal. Case fatality rate of pneumonic plague in Madagascar is close to 75%. [25]

Confounding factors

Rural to urban

When an endemic disease, such as Ebola or plague, is introduced to a new geographic area that is densely populated with international shipping routes, it increases transmission rates and leads to severe outbreaks and potential pandemics. Although urban areas like Antananarivo and Mahajanga are more affluent, they are still impoverished in global comparison. Insufficient waste management, lack of clean water, and poor infrastructure are all issues that are breeding grounds for rats and fleas and therefore perpetuate plague transmission in urban areas. [28] Furthermore, the rat-to-flea cycle of transmission has not changed since the first pandemic of plague. This type of consistency allows the organism to become more infectious.

Rats and fleas

High rates of plague transmission have been associated with low rat abundance and high volume of flea vectors. [26] Historically, rats who acted as hosts to the flea vector subsequently died once they were infected with plague. However, the organism evolved and scientists are now finding that rats are not dying from plague. This means that plague survives longer in the host and allows for the bacteria to live longer and potentially infect more people. The elevation of the mountains where most of the agriculture takes place, in addition to the ideal climate that allows rats and fleas to prosper, scientists have seen plague thrive in Madagascar's climate compared to other countries where there is endemic plague.

Evolution of bacteria

Scientists discovered three new strains of Y. pestis in Madagascar in 2017. Additionally, one strain of Y. pestis was found to be resistant to antibiotic treatment. [18] Because of plague moving from rural to urban areas, there is increased risk for transmission to other countries. Urban areas that are a major transportation hub for shipping and recreation are at high risk for transmitting plague to nearby countries.

Agriculture

Plague in Madagascar is predominantly a rural disease related to agricultural activities. Plague "season" (October through April) coincides with the hot and rainy season in the agricultural highlands. Rats do not thrive in cold climate, and therefore are more prevalent during this time of year. Rice is a vital crop in Madagascar, and due to the high prevalence of fleas and rats in agricultural areas, plague bacteria often infects crops and soil. Many scientists have found that the plague bacteria Y. pestis can live in soil for months at a time. [29]

Burial practices

In addition to agricultural factors that increase prevalence of plague, burial practices in Madagascar also spread disease. Famadihana is a burial practice in Madagascar that is practiced among the Malagasy people. It is commonly known as "turning of the bones." Family members exhume their deceased family members from the family crypts and wrap them up in fresh cloth. Then, they dance around the crypt with the body to live music. This custom is based on a belief that the dead do not join the rest of their ancestors until their body reaches full decomposition with appropriate ceremonies. This process could take up to several years and involves direct contact with corpses. This burial practice perpetuates the spread of plague among other diseases. [30]

Poverty

Plague is symptomatic of poverty. Rats and fleas thrive in rural and urban areas of Madagascar due to the impoverishment of the country. Lack of proper infrastructure, lack of sanitation and waste removal, little clean water, and scarce health facilities create a perfect breeding ground for rats and fleas to thrive. [31] Although plague is prevalent in other countries, Madagascar has the highest fatality and accounts for 30% of all plague cases largely due to poverty and lack of health resources like antibiotics and proper testing. Furthermore, outbreaks of plague have become increasingly more severe due to bubonic plague going untreated and developing into pneumonic plague. Once plague becomes pneumonic, it is significantly more contagious and is transmittable person to person. [27]

Severity

Recently, plague outbreaks have become increasingly more severe. The most recent outbreak in August 2017 is the worst to date with over 1,800 confirmed cases of plague. Of these confirmed cases, 1,100 of them were cases of pneumonic plague. 114 districts of Madagascar were affected by the plague outbreak. Usually, endemic plague only affects around 20 rural districts. [27] This outbreak was different in nature due to the fact that the plague shifted from rural geographic location to urban geographic location. Plague was found in major shipping ports like Mahajanga and in the capital Antananarivo. The capital alone is home to 2.7 million people. [29] Plague moving into urban areas increased transmission rates due to the high volume of people living in these areas and the amount of trade traffic that occurs on a daily basis.

Response to the disease

Madagascar proposed a National Plague Control Program, which is a surveillance program run by the government and the Ministry of Health that is based on immediate notification of every suspected case of plague. Every case reported to the National Plague Control Program is treated with antibiotics. In addition to this course of treatment, insecticide is brought to the home or work for flea control. Although the ideas and intentions of the National Plague Control Program are good and in theory could be very beneficial to treating and preventing outbreaks of plague, severe economic limitations make the execution of this program less than ideal. Furthermore, disparities in rural areas compared to urban areas make accessibility and testing in rural areas challenging. [28] Economic resources need to be strengthened before this program can live up to its full potential. After the most recent, major outbreak, the WHO created a Crisis Emergency Committee to monitor the situation. They deployed epidemiologists, doctors, and risk management coordinators in order to coordinate surveillance, facilitate tracing contacts, oversee case management, administer isolation protocol, and distribute supplies. In addition to the new committee, Madagascar reallocated funds in order to help with isolation, treatment, and supplies. [27] These solutions to the outbreak helped, as cases of plague declined and hospitalized patients decreased in volume.

Other countries

Twelve more cases of suspected plague appeared in the Seychelles days after the death of a 34-year-old male who had recently traveled to Madagascar and who was confirmed as having pneumonic plague on 10 October 2017. [32] Air Seychelles suspended all flights to Madagascar. [33] More sophisticated tests later showed that the infection was not plague. [12]

A South African basketball player who contracted plague while attending a tournament in Madagascar was successfully treated and returned home. [34] The type of plague the player had was not reported, but one of the cases in the Seychelles who died of pneumonic plague was thought to have attended the same tournament. [35]

The World Health Organization warned that there was a high risk the disease could spread to nine other countries in Africa and the Indian Ocean (Ethiopia, Kenya, Tanzania, Mozambique, South Africa, Seychelles, Comoros, Reunion, and Mauritius) because of frequent trade and travel with Madagascar. [11]

See also

Related Research Articles

<span class="mw-page-title-main">Black Death</span> 1346–1353 pandemic in Eurasia and North Africa

The Black Death was a bubonic plague pandemic occurring in Western Eurasia and North Africa from 1346 to 1353. It is the most fatal pandemic recorded in human history, causing the deaths of 75–200 million people, peaking in Europe from 1347 to 1351. Bubonic plague is caused by the bacterium Yersinia pestis spread by fleas, but during the Black Death it probably also took a secondary form, spread by person-to-person contact via aerosols, causing pneumonic plague.

<span class="mw-page-title-main">Plague (disease)</span> Disease caused by Yersinia pestis bacterium

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. 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 the blood and can cause tissues to turn black and die.

<i>Yersinia pestis</i> Species of bacteria, cause of plague

Yersinia pestis is a gram-negative, non-motile, coccobacillus bacterium without spores that is related to both Yersinia enterocolitica and Yersinia pseudotuberculosis, the pathogen from which Y. pestis evolved and responsible for the Far East scarlet-like fever. It is a facultative anaerobic organism that can infect humans via the Oriental rat flea. It causes the disease plague, which caused the Plague of Justinian and the Black Death, the deadliest pandemic in recorded history. Plague takes three main forms: pneumonic, septicemic, and bubonic. Yersinia pestis is a parasite of its host, the rat flea, which is also a parasite of rats, hence Y. pestis is a hyperparasite.

<span class="mw-page-title-main">Pneumonic plague</span> Severe lung infection

Pneumonic plague is a severe lung infection caused by the bacterium Yersinia pestis. Symptoms include fever, headache, shortness of breath, chest pain, and coughing. They typically start about three to seven days after exposure. It is one of three forms of plague, the other two being septicemic plague and bubonic plague.

<span class="mw-page-title-main">Tularemia</span> Infectious disease caused by the bacterium Francisella tularensis

Tularemia, also known as rabbit fever, is an infectious disease caused by the bacterium Francisella tularensis. Symptoms may include fever, skin ulcers, and enlarged lymph nodes. Occasionally, a form that results in pneumonia or a throat infection may occur.

<span class="mw-page-title-main">Septicemic plague</span> Human disease caused by Yersinia pestis

Septicemic plague is one of the three forms of plague, and is caused by Yersinia pestis, a gram-negative species of bacterium. Septicemic plague is a systemic disease involving infection of the blood and is most commonly spread by bites from infected fleas. Septicemic plague can cause disseminated intravascular coagulation and is always fatal when untreated. The other varieties of the plague are bubonic plague and pneumonic plague.

<span class="mw-page-title-main">Third plague pandemic</span> Bubonic plague pandemic, beginning 1855

The third plague pandemic was a major bubonic plague pandemic that began in Yunnan, China, in 1855. This episode of bubonic plague spread to all inhabited continents, and ultimately led to more than 12 million deaths in India and China, and at least 10 million Indians were killed in British Raj India alone, making it one of the deadliest pandemics in history. According to the World Health Organization, the pandemic was considered active until 1960 when worldwide casualties dropped to 200 per year. Plague deaths have continued at a lower level for every year since.

John Ashburton Thompson was a British-Australian physician and an international authority on plague and leprosy.

Globalization, the flow of information, goods, capital, and people across political and geographic boundaries, allows infectious diseases to rapidly spread around the world, while also allowing the alleviation of factors such as hunger and poverty, which are key determinants of global health. The spread of diseases across wide geographic scales has increased through history. Early diseases that spread from Asia to Europe were bubonic plague, influenza of various types, and similar infectious diseases.

<span class="mw-page-title-main">Bubo</span> Inflammation of the lymph nodes

A bubo is adenitis or inflammation of the lymph nodes and is an example of reactive lymphadenopathy.

<span class="mw-page-title-main">Bubonic plague</span> Human and animal disease

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, is another symptom. Occasionally, swollen lymph nodes, known as "buboes", may break open.

Theories of the Black Death are a variety of explanations that have been advanced to explain the nature and transmission of the Black Death (1347–51). A number of epidemiologists from the 1980s to the 2000s challenged the traditional view that the Black Death was caused by plague based on the type and spread of the disease. The confirmation in 2010 and 2011 that Yersinia pestis DNA was associated with a large number of plague sites has led researchers to conclude that "Finally, plague is plague."

The 1994 plague in India was an outbreak of bubonic and pneumonic plague in south-central and western India from 26 August to 18 October 1994. 693 suspected cases and 56 deaths were reported from the five affected Indian states as well as the Union Territory of Delhi. These cases were from Maharashtra, Gujarat, Karnataka, Uttar Pradesh, Madhya Pradesh and New Delhi. There are no reports of cases being exported to other countries.

The San Francisco plague of 1900–1904 was an epidemic of bubonic plague centered on San Francisco's Chinatown. It was the first plague epidemic in the continental United States. The epidemic was recognized by medical authorities in March 1900, but its existence was denied for more than two years by California's Governor Henry Gage. His denial was based on business reasons, to protect the reputations of San Francisco and California and to prevent the loss of revenue due to quarantine. The failure to act quickly may have allowed the disease to establish itself among local animal populations. Federal authorities worked to prove that there was a major health problem, and they isolated the affected area; this undermined Gage's credibility, and he lost the governorship in the 1902 elections. The new governor, George Pardee, implemented public-health measures and the epidemic was stopped in 1904. There were 121 cases identified, resulting in 119 deaths.

<span class="mw-page-title-main">Sylvatic plague</span> Infectious bacterial disease

Sylvatic plague is an infectious bacterial disease caused by the plague bacterium that primarily affects rodents, such as prairie dogs. It is the same bacterium that causes bubonic and pneumonic plague in humans. Sylvatic, or sylvan, means 'occurring in woodland,' and refers specifically to the form of plague in rural wildlife. Urban plague refers to the form in urban wildlife.

<span class="mw-page-title-main">Urban plague</span> Infectious disease affecting rodents

Urban plague is an infectious disease among rodent species that live in close association with humans in urban areas. It is caused by the bacterium Yersinia pestis which is the same bacterium that causes bubonic and pneumonic plague in humans. Plague was first introduced into the United States in 1900 by rat–infested steamships that had sailed from affected areas, mostly from Asia. Urban plague spread from urban rats to rural rodent species, especially among prairie dogs in the western United States.

<span class="mw-page-title-main">1924 Los Angeles pneumonic plague outbreak</span> Disease outbreak in Los Angeles, California

The 1924 Los Angeles pneumonic plague outbreak was an outbreak of the pneumonic plague in Los Angeles, California that began on September 28, 1924, and was declared fully contained on November 13, 1924. It represented the first time that the plague had emerged in Southern California; plague outbreaks previously surfaced in San Francisco and Oakland. The outbreak killed 30 people and infected several more. Public health officials credited the lessons learned from the San Francisco outbreak with saving lives, and swiftly implemented preventative measures, including hospitalization of the sick and all their contacts, a neighborhood quarantine, and a large-scale rat eradication program. The epicenter of the plague was in the Macy Street District, primarily home to Mexican immigrants. Racism against Mexican Americans tainted the reaction to the plague, an issue not made public until the outbreak concluded. This outbreak was the last instance of aerosol transmission of the plague and the last major plague outbreak in the United States.

<span class="mw-page-title-main">Feline zoonosis</span> Medical condition

A feline zoonosis is a viral, bacterial, fungal, protozoan, nematode or arthropod infection that can be transmitted to humans from the domesticated cat, Felis catus. Some of these diseases are reemerging and newly emerging infections or infestations caused by zoonotic pathogens transmitted by cats. In some instances, the cat can display symptoms of infection and sometimes the cat remains asymptomatic. There can be serious illnesses and clinical manifestations in people who become infected. This is dependent on the immune status and age of the person. Those who live in close association with cats are more prone to these infections. But those that do not keep cats as pets are also able to acquire these infections because of the transmission can be from cat feces and the parasites that leave their bodies.

Globally about 600 cases of plague are reported a year. In 2017 and November 2019 the countries with the most cases include the Democratic Republic of the Congo, Madagascar, and Peru.

The Neolithic decline was a rapid collapse in populations between 5000 and 6000 years ago during the Neolithic period in western Eurasia. The specific causes of that broad population decline are still debated. While heavily populated settlements were regularly created, abandoned, and resettled during the Neolithic, after around 5400 years ago, a great number of those settlements were permanently abandoned. The population decline is associated with worsening agricultural conditions and a decrease in cereal production. Other suggested causes include the emergence of communicable diseases spread from animals living in close quarters with humans.

References

  1. "WHO | Plague in Madagascar". WHO. Archived from the original on 14 February 2015. Retrieved 19 April 2020.
  2. "WHO | Plague – Madagascar". WHO. Archived from the original on 28 November 2017. Retrieved 7 August 2020.
  3. "Madagascar: eighteen dead from Bubonic Plague, five in hospital since 1 January 2008". Archived from the original on 9 May 2009.
  4. Australian AFP news sources
  5. "Bubonic plague outbreak kills 32 in Madagascar". Theguardian.com. Associated Press. 20 December 2013. Retrieved 10 October 2017.
  6. "Weekly Bulletin on Outbreaks and Other Emergencies" (PDF). WHO Africa. Retrieved 23 January 2018.
  7. 1 2 3 4 "WHO | Plague – Madagascar". WHO. Archived from the original on 23 November 2014.
  8. "Madagascar plague outbreak kills 40, says WHO". BBC News. 21 November 2014.
  9. 1 2 3 4 "WHO | Plague in Madagascar". WHO. Archived from the original on 14 February 2015.
  10. "Madagascar Plague Outbreak: External Situation Report #5 - 20 October 2017". ReliefWeb. 21 October 2017. Retrieved 22 October 2017.
  11. 1 2 "Echoes of Ebola as plague hits Madagascar. Science Magazine - October 27, 2017 - 14". www.sciencemagazinedigital.org. Retrieved 27 October 2017.
  12. 1 2 McNeil, Donald G. Jr. (2 November 2017). "Deadly Plague Outbreak in Madagascar Appears to Wane". The New York Times. Retrieved 25 November 2017.
  13. "Plague - Madagascar (28): fatal, WHO 2017-11-02 15:20:33". www.promedmail.org. International Society for Infectious Diseases. Retrieved 3 November 2017.
  14. "Madagascar plague: mitigating the risk of regional spread". World Health Organization. Retrieved 3 November 2017.
  15. Ireland, Ben (3 January 2018). "Madagascar declares the end of plague epidemic". Travel Weekly. Retrieved 26 March 2018.
  16. "How the Plague Outbreak in Madagascar Got So Bad, So Fast". Live Science. 18 October 2017. Retrieved 21 October 2017.
  17. World Health Organization. Regional Office for Africa, Health Emergencies Programme (2017). Plague Outbreak Madagascar External Situation Report 07. World Health Organization (Report). hdl: 10665/259385 . Retrieved 3 November 2017.
  18. 1 2 Riehm, Julia M.; Projahn, Michaela; Vogler, Amy J.; Rajerison, Minoaerisoa; Andersen, Genevieve; Hall, Carina M.; Zimmermann, Thomas; Soanandrasana, Rahelinirina; Andrianaivoarimanana, Voahangy; Straubinger, Reinhard K.; Nottingham, Roxanne; Keim, Paul; Wagner, David M.; Scholz, Holger C. (12 June 2015). "Diverse genotypes of Yersinia pestis caused plague in Madagascar in 2007". PLOS Neglected Tropical Diseases. 9 (6): e0003844. doi: 10.1371/journal.pntd.0003844 . PMC   4466568 . PMID   26069964.
  19. "PLAGUE - MADAGASCAR (21): FATAL, NUMBERS GROWING, WHO, MINISTRY OF HEALTH". www.promedmail.org. Retrieved 21 October 2017.
  20. "The Black Death is killing people: Why is Madagascar facing its worst plague outbreak in years?". Los Angeles Times. 13 October 2017. Retrieved 21 October 2017.
  21. "Madagascar plague outbreak case count reaches 500 - Outbreak News Today". Outbreak News Today. 11 October 2017. Retrieved 21 October 2017.
  22. "Plague cases on the decline, but 9 countries on alert". CNN. 13 November 2017.
  23. "WHO | Plague – Madagascar". WHO. Archived from the original on 17 November 2017.
  24. Raoult, D., Mouffok, N., Bitam, I., Piarroux, R., & Drancourt, M. (2013). Plague: history and contemporary analysis. Journal of Infection, 66(1), 18-26.
  25. 1 2 3 Centers for Disease Control and Prevention (2018). Plague. 2018.
  26. 1 2 Andrianaivoarimanana, V., Kreppel, K., Elissa, N., Duplantier, J. M., Carniel, E., Rajerison, M., & Jambou, R. (2013). Understanding the persistence of plague foci in Madagascar. PLoS Neglected Tropical Diseases, 7(11), e2382.
  27. 1 2 3 4 5 World Health Organization (2018). Plague – Madagascar. 2018.
  28. 1 2 3 Miarinjara, A., & Boyer, S. (2016). Current perspectives on plague vector control in Madagascar: Susceptibility status of Xenopsylla cheopis to 12 insecticides. PLoS Neglected Tropical Diseases, 10(2), e0004414.
  29. 1 2 Chanteau, S., Ratsifasoamanana, L., Rasoamanana, B., Rahalison, L., Randriambelosoa, J., Roux, J....Rabeson, D. (1998). Plague, a Reemerging Disease in Madagascar. Emerging Infectious Diseases, 4(1), 101-104. doi : 10.3201/eid0401.980114.
  30. Ramasindrazana, B., Andrianaivoarimanana, V., Rakotondramanga, J. M., Birdsell, D. N., Ratsitorahina, M., & Rajerison, M. (2017). Pneumonic Plague Transmission, Moramanga, Madagascar, 2015. Emerging Infectious Diseases, 23(3), 521.
  31. Migliani, R., Chanteau, S., Rahalison, L., Ratsitorahina, M., Boutin, J. P., Ratsifasoamanana, L., & Roux, J. (2006). Epidemiological trends for human plague in Madagascar during the second half of the 20th century: a survey of 20 900 notified cases. Tropical Medicine & International Health, 11(8), 1228-1237.
  32. McNeil, Donald G. Jr. (11 October 2017). "Seychelles Reports a Case of Plague". The New York Times. Retrieved 21 October 2017.
  33. "Air Seychelles suspends flights to Madagascar after plague outbreak". Seychelles news agency. 6 October 2017. Retrieved 24 October 2017.
  34. "South African successfully treated after contracting plague". TimesLive. Retrieved 21 October 2017.
  35. "Published Date: 2017-10-12 12:46:43 Subject: <PRO/AH/EDR> Plague - Madagascar (17): South Africa (ex Madagascar) RFI". www.promedmail.org. Retrieved 21 October 2017.