PUBLIC HEALTH CONCERN

Humans are highly susceptible to F tularensis. The viru­lence of the strain, dose and route of exposure are all important factors influencing the clinical form and sever­ity of the disease in humans.

Outdoor activities expose people to infected animals, bites by infected arthropods or contact with contaminated surface waters. The most frequent presentation of clinical signs in humans are inflammation and later ulceration at the primary site of infection, with swelling of regional lymph nodes, which may become abscessed. Generally, the course of the clinical disease includes sudden onset of fever, generalized aches, inflammation of the upper respi­ratory tract with nasal discharge, vomiting, malaise and anorexia. Seven clinicopathological forms of tularaemia have been described in human medicine: ulceroglandular, glandular, oculoglandular, oropharyngeal, pneumonic, typhoidal and septicaemic(¹4).

I nfection of humans by F tularensis is treatable with antibiotics. People can minimize their potential exposure to F. tularensis. Publicizing epizootics and providing infor­mation on how to protect oneself are important. To prevent contact transmission, rubber gloves should be worn by trappers or hunters when skinning those species commonly associated with tularaemia. As for arthropod transmitted infection, the use of insect repellent, protec­tive clothing and frequent body searches with prompt removal of ticks can greatly reduce the risk of infection. Meat from potentially infected animals should be well cooked. Untreated water from lakes and streams should not be consumed. Vaccination has generally not been widely applied, but vaccines have been used for high- risk situations, typically for laboratory researchers. Devel­opment of various vaccine candidates, including acellular subunit, killed whole cell and live attenuated, has taken place in recent years, but a licensed vaccine does not exist yet.