Abstract
Plague, an infectious disease caused by the bacillus Yersinia pestis, is primarily a disease in rodents
and is carried by fleas. Humans accidentally contract the disease via flea bites or exposure to infected
animals. There are records of several plague pandemics in the past that produced enormous mortality.
Today the incidence of plague has been substantially reduced owing to the effectiveness of antimicrobials,
improved sanitation and effective pest control. Currently, however, the disease seems increasingly to be
re-emerging, especially in Africa. Climate change and the global fluctuation in politics and poor economics
may be related partly to the migration of human populations into plague endemic areas. Also,
plague bacilli can be used for modern-day bioterrorism. Because the tendency of plague epidemics to
occur is increasingly alarming, the World Health Organization has categorized plague as a re-emerging
disease.
This communication may serve as a refresher course on plague so that those in Thai medical circles
may prepare for future outbreaks.
