Epidemiology of echinococcosis/hydatidosis in Anambra State, Nigeria.

The prevalence of hydatidosis in cattle, goats and pigs slaughtered in Anambra State, eastern Nigeria during 1973 to 1979, as determined from official meat inspection records, was 7/373,242 (0.002%), 249/476,249 (0.05%) and 1/31,005 (0.003%), respectively. Special point surveys conducted from September 1979 to February 1980 and from March 1985 to September 1987 in two of the slaughterhouses that officially recorded zero infection rates also found no infection in the 551 cattle, 3830 goats and 2126 pigs examined. Similarly, none of the 80 dogs obtained from some of the rural communities in the localities served by these slaughterhouses harboured tapeworms (Echinococcus) at necropsy. Information obtained from rural health centres and some rural and urban-located hospitals, including records of hospital admissions, revealed insufficient awareness of the nature and importance of the disease in man and no evidence even of suspected cases. The apparent absence of infection in humans was confirmed by records at the main specialist hospital in the area, which showed that only one case of human hydatid disease had ever been diagnosed by that hospital. The most important factors that might have been responsible for the virtual absence of canine and human infections include the extremely low infection rates in food animals, limited access by dogs to offal, limited contact between dogs and potential domestic intermediate hosts of hydatid, and absence of a wild-life cycle.