Fact Sheet N°
Plague is primarily a disease of rodents which can affect humans. It is transmitted between rodents by rodent fleas and can be transmitted to people through infected rodent flea bites. It can also be transmitted to humans through direct contact with infected animal tissue. As with many primarily zoonotic diseases, where the disease is transmitted from vertebrae animals to humans, plague is a very severe disease in people, with a case-fatality ratio of 50%-60% if left untreated.
There are three main forms of plague in humans: bubonic, septicaemic and pneumonic.
Plague is endemic in many countries in Africa, the Americas and Asia. In 1999, 14 countries reported 2,603 cases to WHO (including 212 deaths). These figures are comparable with the annual average figures (2,547 cases, 181 deaths) for the previous 10 years (1988-1997). Over the past decade, 76.2% of the cases and 81.8% of the deaths were reported from Africa.
Treatment: Effective treatment methods enable almost all plague patients to be cured if diagnosed in time. These methods include antibiotics and supportive therapy.
Prevention: The objective of preventive measures is to reduce the likelihood of people being bitten by infected fleas, of having direct contact with infective tissues, or of being exposed to patients with pneumonic plague. Important preventive measures include the following:
Case recognition and medical intervention:
Vaccination: Plague vaccines are available worldwide, but are not recommended for immediate protection in outbreak situations. Vaccination is only recommended for high-risk groups, e.g. health workers and laboratory personnel who are constantly exposed to the risk of contamination.
Epidemiological and epizootical investigation and emergency control:
Surveillance and control
The use of these measures has led to a sharp reduction in human plague throughout the world. Today the distribution of plague coincides with the geographical distribution of its natural foci in some countries in Africa (e.g. Uganda, Madagascar, Democratic Republic of the Congo, United Republic of Tanzania) and Latin America.
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