Prevention of rickettsial disease

Very little study has been done on measures to prevent rickettsial diseases. Accordingly recommendations are based on the common-sense application of measures which have been shown to be effective in the control of other insect-vector transmitted diseases. Additionally, there are currently no vaccines available for the prevention of rickettsial diseases.

The most important aspect of prevention of rickettsial diseases is likely to be vector avoidance. The chigger mite is the vector of scrub typhus and lives on low vegetation, in particular of scrubland. Avoidance of contact with vegetation in areas with high endemicity (which is often unrealistic for those who live off the land) is one possibility. Another is taking precautions to prevent being bitten, including the wearing of long trousers and sleeves and avoiding lying on the ground. Insect repellents (e.g. DEET) and insecticide-impregnated clothing (e.g. permethrin) are also likely to be effective deterrents. For murine typhus, where the vector is the flea, avoidance of animals with fleas (the reservoir), including domestic animals and rodents, rodent-control and flea-control (vector-control) measures of domestic animals are recommended. The role of reservoir-control, i.e. rodent-control, measures in scrub typhus is uncertain.

There is scant evidence on the effectiveness of chemoprophylaxis for the prevention of rickettsial disease, although breakthrough disease has occurred in those supposedly taking doxycycline malaria prophylaxis. Early identification and removal of the vector may limit the likelihood of transmission of the pathogen, although these may be hard to identify (e.g. chigger mites are very small). Evidence on the use of post-exposure prophylaxis is absent.