a1 Division of Biologics, Public Health Laboratory Service Centre for Applied Microbiology and Research, Porton Down, Salisbury, Wiltshire SP4 0JG, UK
a2 Section of Infectious Diseases, Faculty of Medicine, Erciyes University, 38039 Kayseri, Turkey
a3 Etosha Ecological Institute, P. O. Okaukuejo, via Outjo, 9000, Namibia
a4 State Veterinary Service, Block 7. Chalfont Drive, Nottingham NG8 3SN, UK
Results are presented from a number of epidemiological studies using enzyme immunoassays (EIA) based on the purified anthrax toxin antigens, protective antigen, lethal factor and oedema factor. Studies on sera from a group of 62 human anthrax patients in Turkey and from cattle in Britain following two unrelated outbreaks of anthrax show that EIA using protective antigen can be a useful diagnostic aid and will detect subclinical infections in appropriate circumstances. A serological survey on wildlife in the Etosha National Park, Namibia, where anthrax is endemic, showed that naturally acquired anthrax-specific antibodies are rare in herbivores but common in carnivores; in carnivores, titres appear to reflect the prevalence of anthrax in their ranges. Problems, as yet unresolved, were encountered in studies on sera from pigs following an outbreak of anthrax on a farm in Wales.
Clinical details, including treatment, of the human and one of the bovine outbreaks are summarized and discussed in relation to the serological findings.
(Accepted October 15 1991)