Rickettsial Infections


Ventral view of a male body louse,
Pediculus humanus var. corporis
This section provides information on one of the nine zoonotic diseases which have been identified by a experts in a national consultation organised by RCZI in June, 2008  as focus or priority diseases for the next five years.

Rickettsial Infections are caused by rickettsiae which are small, gram negative bacilli adapted to obligate intracellular parasitism and transmitted by arthropod vectors. These organisms are primarily parasites of arthopods such as lice, fleas, ticks and mites in which they are found in the alimentary canal. In vertebrates including humans, they infect the vascular endothelium and reticuloendothelial cells. Important rickettsial diseases in India are Scrub Typhus; Epidemic Typhus; Endemic Typhus and Tick Typhus. Rickettsial diseases are difficult to diagnose both clinically and in the laboratory. As a result, this group of diseases have been grossly underreported in India. In 2004, 198 cases were found positive and in 2008, 252. Recently outbreaks have been reported from West Bengal and Himachal Pradesh.

Public Health Measures

Confirmed and Suspected Outbreaks of Rickettsial Infections