Human taenia solium cysticercosis in the district of Angonia, Mozambique : prevalence rates and clinical aspects

Abstract

Cysticercosis is emerging as a serious public health and agricultural problem in countries of Eastern and Southern Africa (ESA). Caused by a pork tapeworm, this zoonotic disease forms cysts in the tissues of pigs and humans that reduce the value of pigs, makes pork unsafe to eat and can lead to neurological disease including epilepsy and death in humans. It occurs where pigs range freely, sanitation is poor, and meat inspection is absent or inadequate, and thus strongly associated with poverty and smallholder farming. Although theoretically easy to control and declared eradicable cysticercosis remains neglected in ESA due to lack of information and awareness about the extent of the problem, lack of suitable diagnostic and management capacity, and appropriate prevention and control strategies. Mozambique is still lacking epidemiological data on human taeniosis and cysticercosis and it is not possible to draw firm conclusions on its prevalence and geographical distribution. Until now, all the work developed in this area has been exploratory and of a piloting nature. The objectives of the proposed study were 1) to determine the prevalence of neurocysticercosis (NCC) in humans in the district of Angonia, 2) determine the distribution of epilepsy and 3) explore possible relationships between NCC and epilepsy. The present study was conducted in the district of Angonia, located in Tete province in the central region of Mozambique. 1723 individuals from 16 towns of the two administrative posts, Ulongue and Domue in the Angonia district were included. The proportion of interviewed people reporting symptoms of epilepsy was 15,6% (268) while 84,4% (1454) reported no symptoms. A total of 249 (14,5%) were ELISA Ag positive for cysticercosis and 1774 (85,5%) were negative. Of those with positive ELISA Ag 118 (47,4%) had a history of epilepsy. CT scans were performed on 107 (90,7% ) of the 118 and 44 (33,6% ) of the ELISA Ag negative with symptoms suggestive of epilepsy. Of the ELISA Ag positive group, 77 (72%) showed abnormal scans suggesting NCC, compared to the 8 (18,2% ) in the negative group. 151 people were also submitted to EEG exam and 79 presented abnormal results. Considering the type of seizures of the total of 79 individuals, 73,4% (58) were affected by partial seizures and the remaining by generalized seizures. We concluded that T. solium NCC appears to be an important but overlooked cause of epilepsy in Angonia. The main recommendation for reducing the prevalence of human cysticercosis is to provide more effective education campaigns and proper sanitary facilities with improved health care and socioeconomic status of the people in developing countries, aimed at preventing both T. solium infection and cysticercosis.