Prevalence of cysticercosis in cattle slaughterhouses in the western region of Minas Gerais, Brazil (2013-2020): Influence of sanitary regulations in reducing risks to human health.

Abstract

Bovine cysticercosis is a foodborne zoonosis that has a worldwide distribution, and its highest prevalence is found in developing countries with a large volume of cattle production, such as Brazil. The objective was to evaluate the prevalence of cysticercosis during seven years in three slaughterhouses located in the western region of Minas Gerais state, Brazil, and the impacts of the legislation on the identification and destination of infected carcasses. Three slaughterhouses (Sl) were selected for this study with averages of 200 (SlA), 721 (SlB) and 1138 (SlC) bovines slaughtered per day. The monthly number of slaughtered cattle, infected carcasses with cysticercosis and destination were used to calculate the condemnation occurrence index (COI) and the adjusted seasonal index (ASI). To assess the impact of the legislation, the prevalence rate and destination of infected carcasses were subdivided into the PRE (January 2013 to March 2017) and POST (April 2017 to December 2020) period of Decree 9013 of 2017 and the results were compared by chi-square (P<0.05). SlA recorded the highest cysticercosis rate with 1.54 % and SlC the lowest rate with 0.33 %. In addition, it was observed that in the POST period there was an increase in the identification of infected carcasses in SlA and B (P<0.05). The POST period also resulted in a change in the relative frequency of infected carcasses destination in the three slaughterhouses (P<0.05). The ASI identified an increase in infected carcasses in February and a decrease in November for SlB, proving to be an important tool for planning the inspection team trainings. These results show that the disease is still present in the studied region and highlight the benefits of using the One Health concept in the evaluation of a time series prevalence of bovine cysticercosis by: identifying seasonality of the disease, trends during the time period and impacts brought by updates in the national sanitary legislation.