PLAGUE – MADAGASCAR: FATAL

An unusually deadly seasonal outbreak of plague has gripped the island nation of Madagascar. As of [Fri 6 Oct 2017], 258 have been sickened and 36 have died just since August 2017, according to Madagascar’s Ministry of Public Health. To try to stifle the spread, the government has forbidden public gatherings, including sporting events, and schools have closed for insecticide treatments that kill plague-spreading fleas. People have swarmed pharmacies, desperately seeking face masks and any antibiotics they can get. The WHO on [Fri 6 Oct 2017], announced that it has released 1.5 million [USD] in emergency funds and delivered nearly 1.2 million antimicrobial doses to help combat the outbreak.

Plague, caused by the bacterium _Yersinia pestis_, is endemic to Madagascar and pops up all year-round. But outbreaks can erupt between September to November, with seasonal shifts in rat and flea populations. Rats, which harbour the bacteria, tend to see their populations plump and peak around harvest times in July and August. A boom in the flea population, which transmits the disease, follows in tandem. But as crops are harvested and the weather cools, the rat population shrinks, and the surging, hungry batch of fleas turns to humans.

The island has been battling the disease since it arrived there on steamboats from India in 1898. (The disease still appears in many countries around the world, including the USA, but most epidemics occur in African countries.) Madagascar got a handle on its seasonal outbreaks during the 1950s with the help of antibiotics, insecticides, and better hygiene campaigns. But it lost its grip in the 1990s when it started seeing increases in case counts. In recent years, the country has tallied between 275 and 675 cases annually.

But this year [2017] is different. The disease is spreading not just in rural, agricultural areas; it’s also spreading in cities. As of [Sat 30 Sep 2017], the disease had taken hold in 10 cities across the island, including the capital, Antananarivo.

WHO is concerned that plague could spread further because it is already present in several cities and this is the start of the epidemic season, which usually runs from September to April, Dr. Charlotte Ndiaye, WHO representative in Madagascar, said in a recent statement.

It is also spreading in 2 different ways–by fleas and by people–which some have dubbed a “double plague.” Usually, plague infections arise as bubonic plague, spread by flea bites. In this case–the Black Death scenario–_Y. pestis_ moves from the site of a flea bite on a human to the lymphatic system, taking up residence and inflaming a lymph node. This causes a painful swelling called a bubo, where the infection gets its name. If it is left untreated, the infection can spread to the blood, causing septicaemic plague, or the lungs, causing pneumonic plague.

Pneumonic plague is the most severe form. It can become a life-threatening situation in just 24 hours and can begin to spread from person to person in droplets, coughed or sneezed. Most of the people infected in the current outbreak in Madagascar have the pneumonic form.

Authorities suspect that the outbreak kicked off when a 31-year-old man from the coastal city of Tamatave visited the Ankazobe District in the Central Highlands. On [Sun 27 Aug 2017] during his visit, he developed what he thought were malaria symptoms. Four days later, he was showing respiratory symptoms while taking a shared, public taxi on the way home. He died during the journey, and his body was prepared for burial, without safety precautions, in the Moramanga District Hospital, which was along the way. Health officials linked his case to 31 others, 4 of which resulted in death.

Officials caught on to the outbreak on [Mon 11 Sep 2017], and cases have piled up since then. People all over the island are spooked by the deadly and fast-spreading pneumonic version of the disease. Lines of people have been appearing at local pharmacies before dawn. They hope to get a face-mask and/or antibiotics, which are now in short supply and expensive.

A 50-year-old resident of Antananarivo, told the Agence France-Presse on [Wed 4 Oct 2017], that he and his wife were alarmed by the current outbreak. I’d already visited 6 [pharmacies] this morning and at each one they told me that they didn’t have any more masks, he said. He again left empty-handed.

Local health authorities have been trying to calm residents, telling them that face masks aren’t necessary and that the plague can be treated.Plague is curable if detected in time. Our teams are working to ensure that everyone at risk has access to protection and treatment. The faster we move, the more lives we save, WHO’s Dr. Ndiaye said.

Primary pneumonic plague (one percent of natural plague presentations) arises as a result of inhalation of plague bacilli in infectious aerosols, such as would be produced when there are secondary pneumonic complications in bubonic/septicemic plague.

Primary plague pneumonia has a short incubation period of 1-3 days, after which there is sudden onset of:

  • flu-like symptoms including fever,
  • chills,
  • headache,
  • generalized body pains,
  • weakness and chest discomfort.

A cough develops with sputum production, which may be bloody, and increasing chest pain and difficulty in breathing. As the disease progresses, hypoxia (low oxygen concentration in the blood) and hemoptysis (coughing up blood) are prominent. The disease is invariably fatal unless antimicrobial therapy commences within 24 hours of exposure.

Patients with primary pneumonic plague generate large quantities of infectious aerosols that pose a significant risk to close contacts.

CDC guidelines identify contacts within 2 meters [6.6 feet] as being at greatest risk and do not consider the organism likely to be carried through air ducts or vents. Persons who have been in contact with pneumonic plague patients or handling potentially infectious body fluids or tissues without appropriate protection should receive preventive antimicrobial therapy. The preferred antimicrobial agents for prophylaxis are tetracyclines, quinolones, or chloramphenicol.

Communicated by: ProMED-mail