Human Health Risks Related to Penicillin G and Oxytetracycline Residues Intake Through Beef Consumption and Consumer Knowledge About Drug Residues in Maroua, Far North of Cameroon.

In Cameroon, a leading livestock production country, previous study highlighted the extensive misuse of veterinary drugs in the Far North Region, where we found the second cattle population of the country. Based on former work describing the presence of penicillin G (PEN) and oxytetracycline (OTC) residues in beef sold for human consumption in Maroua, the capital city of the Far North Region, this study was designed to determine the risk of PEN and OTC residue intake via beef consumption by the population of Maroua and to evaluate the consumer's knowledge on drug residues. Dietary exposure determined here was based on the average consumption of beef (found during a survey of 202 households randomly selected in Maroua) and the average concentration of the two antibiotic residues in beef (obtained after liquid chromatography-tandem mass spectrometry analysis of samples of liver and muscle collected from 202 cattle selected randomly in all the slaughterhouses of Maroua) found in our previous studies. The estimated daily intakes per capita of OTC and PEN residues from beef consumption were 22.81 and 2.37 µg, respectively. The risk was then assessed as high [9.6%; range from 6.4 to 15.4% of acceptable daily intake (ADI)] and considerable (2.2% range from 1.5 to 3.5% of ADI) for PEN and OTC residues, respectively. Based on the mean value, it can be concluded that the estimated risk of antibiotic daily intake through beef in Maroua is high (5.9% of ADI). Also, 98% of the surveyed population is not aware that meat can be contaminated by residues of veterinary drugs administered to slaughter animals. This ignorance would also increase the risk of contamination of the population of Maroua with antibiotic residues. This work clearly highlights the high risk of consuming beef by the population of Maroua. Taking into consideration the evidence of the intake of antibiotic residues from others sources, it is therefore very imperative that measures be taken by the government to ensure food safety in order to guarantee the health of the populations of this region in particular and Cameroon in general, hence the need for the establishment of a national food safety plan.

A comparison of Taenia solium and Taenia hydatigena infection in pigs using serological diagnosis and post-mortem inspection methods in Benoué division, North Cameroon.

The metacestodes of Taenia solium and Taenia hydatigena are the cause of cysticercosis in pigs. T. solium is also responsible of the taeniosis/neurocysticercosis complex in humans, constituting a main cause of epilepsy cases across endemic countries. T. hydatigena is non-zoonotic, but its occurrence in pigs contributes significantly to false positive reactions should genus-species serological methods be used for diagnosis of T. solium porcine cysticercosis. T. hydatigena is often considered not common in pigs in Africa compared to T. solium. On the basis of the evidence that these two cestodes coexist in Cameroon, we examined the viscera of 305 pigs for the identification of the metacestodes of T. hydatigena in Bénoué division, North Region of Cameroon. Tongue, masticatory muscles and heart were sliced for the identification of T. solium cysticerci (TMH dissection test). Twenty seven (8.85%) and 16 (5.24%) pigs were found infected with the metacestodes of T. solium and T. hydatigena, respectively. The difference between the two rates of infection was not statistically significant (P > 0.05). Serum samples were also collected for the evaluation of an inhibition ELISA (i-ELISA) specific to antibodies anti- T. solium or anti-T. hydatigena cysticerci. After incubation of these sera with cyst fluid of T. solium, T. hydatigena, T. multiceps multiceps, T. multiceps gaigeri and T. saginata to eliminate cross-reactions among cestodes parasites, the i-ELISA indicated that 26.56% and 28.52% slaughtered pigs had predominant specific antibodies to cyst fluid of T. solium and T. hydatigena, respectively. Combination of TMH dissection test, i-ELISA and a standard indirect ELISA in a Bayesian simulation approach revealed a true prevalence of 19.27% (0.7-49.27, CI 95%) and 24.85% (5.17-48.34, CI 95%) of porcine cysticercosis due to T. solium and T. hydatigena, respectively. These results indicated that T. hydatigena is as prevalent as T. solium in pigs in the North of Cameroon.

Taenia solium taeniosis/cysticercosis in Africa: risk factors, epidemiology and prospects for control using vaccination.

Poor sanitary conditions, free-roaming of domestic pigs and lack of awareness of the disease play an important role in the perpetuation of the Taenia solium taeniosis and cysticercosis in Africa. Traditional pig production systems known as the source of T. solium taeniosis/cysticercosis complex are predominant in the continent, representing 60-90% of pig production in rural areas. It has been reported that T. solium cysticercosis is the main cause of acquired epilepsy in human population and results in considerable public health problems and economic costs to the endemic countries. Although the socioeconomic impact and public health burden of cysticercosis have been demonstrated, up to now no large-scale control programme has been undertaken in Africa. Most disease control trials reported in the literature have been located in Latin America and Asia. This review discusses the risk factors and epidemiology of T. solium cysticercosis in Africa and critically analyzes the options available for implementing control of this zoonotic disease in the continent.

Elimination of Taenia solium transmission to pigs in a field trial of the TSOL18 vaccine in Cameroon.

A pilot field trial of the TSOL18 vaccine was undertaken in Cameroon. Two hundred and forty, 2-3 month-old piglets were distributed to 114 individual households in pairs. Vaccinated animals received three immunisations with 200 microg TSOL18 plus 5 mg Quil A and 30 mg/kg oxfendazole at the time of the second immunisation. Necropsies were undertaken when the pigs were approximately 12 months of age. Viable Taenia solium cysticerci were identified in 20 control pigs (prevalence 19.6%); no cysticerci were found in any of the vaccinated animals (P<0.0001). Combined application of TSOL18 vaccination and a single oxfendazole treatment in pigs may be a relatively simple and sustainable procedure that has the potential to control T. solium transmission in endemic areas and, indirectly, reduce the number of new cases of neurocysticercosis in humans.

Neurocysticercosis and epilepsy in Cameroon.

During January 2002 the frequency of Taenia solium cysticercosis was studied in a series of 504 epileptic patients from 3 rural localities in the West and North-West provinces of Cameroon using an enzyme-linked immunosorbent assay for both circulating antigen (Ag-ELISA) and antibody (Ag-ELISA) detection. Taenia solium antigens were detected in the sera of 1.2% of the patients whereas specific antibodies against the parasite were present in 44.6% of the patients. Significantly less seropositive results in Ab-ELISA were recorded in Batibo than in Bandjoun and Bamendjou, whereas a borderline significant difference was recorded with increasing age. Furthermore, 56.2% of patients with late-onset epilepsy showed antibodies against cysticercosis. Taenia solium cysticercosis appears to be an important cause of epilepsy in Cameroon.