Travel-associated zoonotic bacterial diseases

Bacterial zoonoses are increasingly described in association with travel. Some bacterial zoonoses constitute important causes of post-travel illness. We focus on leptospirosis and rickettsiosis - the most common travel-associated bacterial zoonoses.

Leptospirosis is regarded to be the most common zoonotic disease worldwide. In industrialized countries recreational exposures, both domestic and overseas, are increasingly becoming a major source of infection. Asymptomatic infection is rare among travelers. Rickettsial diseases account for approximately 1.5-3.5% of febrile travelers. In several series of travel-related rickettsioses, the most common travel-related rickettsial disease is Rickettsia africae. Other rickettsioses including Q fever, scrub typhus and murine typhus are considered rare among travelers. Whereas timely diagnosis of both diseases is still based on exposure history, antigen detection tools to aid the diagnosis during the acute illness are under research and far from being available. Due to these constrains, currently, the true incidence of both diseases is probably underestimated.

Both leptospirosis and spotted fever may be rapidly fatal. Empiric doxycycline in severely ill febrile travelers should be considered. There is an urgent need for widely available antigen detection diagnostic tools to improve the detection of leptospirosis and rickettsial infections during the acute illness.