At least five people have died in an outbreak of Pneumonic Plague in Madagascar in the last two weeks. The first death was recorded on 28 August in a public taxi near Tamatave. Two other passengers in the vehicle are believed to have contracted the illness at this time and died in Antanarivo within 24 hours. Since then a further two deaths have occurred, both in the Antanarivo area, and 349 other people have been treated for the disease, and authorities are urging anyone showing symptoms to seek immediate medical help.
Pneumonic Plague is caused by Yersinia pestis, the same Bacterium that causes Bubonic Plague. The Bacterium is indigenous to Madagascar, with outbreaks of Plague being a regular occurrence during the dry season (May to October). The Pneumonic form of the illness is considered particularly worrying, as in this instance the lungs become infected with the disease, leading to coughing, which can spread the disease, and pneumonia, which can rapidly kill patients. Yersinia pestis generally responds well to antibiotics, but the alarm caused by the diseases it causes can provoke excessive use, leading to shortages when they are most needed.
Mass of Yersinia pestis Bacteria. Wikipedia.
Yersinia pestis is a Gram-negative, facultatively anaerobic (i.e. capable of using oxygen, but not needing it), rod-shaped Gammaproteobacteria, related to other pathogenic Bacteria such as Vibrio cholerae (Cholera), and Esherchia coli (food poisoning).It is a zoonotic disease, naturally occurring in a variety of Rodents, but capable of infecting Humans, typically via Fleas, which spread the disease by biting both their regular Rodent hosts and Humans. Zoonotic diseases can be particularly dangerous, as Humans are not part of their natural life-cycle, with the effect that they are not under evolutionary pressure to keep Human hosts alive in order to perpetuate themselves. Such diseases typically have short duration and a high fatality rate, though epidemics usually burn out quickly.
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