Sylvatic plague, still another form, is carried by other rodents, e.g., squirrels, rabbits, chipmunks, in rural or wooded areas where they are prevalent. An overwhelming infection of the blood may cause death in three or four days, even before other symptoms appear. Such antibiotics as streptomycin and tetracycline greatly reduce the mortality rate.
Vaccine is available for preventive purposes.
Rodent control is important in areas of known infection. The great plague of London in 1665 is recorded in many works of literature. Quarantine measures helped contain the disease, but serious epidemics continued to occur even in the 19th cent. The disease is still prevalent in parts of Asia. Because the number of cases of plague has been increasing annually, it is categorized as a re-emerging infectious disease by the World Health Organization.