A Systematic Review and Meta-Analysis of the Efficacy of Biosecurity in Disease Prevention and Control in Livestock Farms in Africa.

In Africa, livestock production plays a crucial role for sustainable food security and economic growth. However, the development of this sector has been delayed by livestock diseases, one of the main constraints, which can cause important production and economic losses. To overcome these constraints, farmers extensively use antimicrobials, which in turn can lead to antimicrobial resistance (AMR), one of the main threats to global health and food security. Biosecurity has been identified as a key strategy to reduce livestock diseases. Therefore, the current systematic review and meta-analysis, conducted according to the Cochrane guideline, aimed at determining the efficacy of biosecurity in preventing and controlling infectious diseases in livestock farms in Africa. Of the 1408 records retrieved from five different databases, only 16 met the inclusion criteria. These studies were conducted in Egypt (31.2%), Nigeria (31.2%), Uganda (18.8%), Ethiopia (12.5%) and Tunisia (6.3%) and concerned poultry (62.4%), pigs (18.8%) and cattle (18.8%). Investigations focused mainly on avian influenza (AI) (15.0%) and coccidiosis (10.0%) in poultry and African swine fever (ASF) (10.0%) in pigs. In poultry farms, the results of the pairwise meta-analysis showed that biosecurity measures related to visitors and farmworkers could be effective at reducing the risk of introduction and spread of AI viruses (odds ratio [OR] = 0.48; 95% confidence interval [CI] 0.28-0.82). Moreover, inadequate biosecurity seemed to be a factor promoting coccidiosis (OR = 4.20; 95% CI 2.4-7.4) and AI (OR = 1.74; 95% CI 1.23-2.48). Prevention of ASF was significantly associated with the application of biosecurity measures related to animals' transport, removal of carcasses and manure (OR = 0.33; 95% CI 0.12-0.88). Despite their importance, these findings cannot be translated to the entire African continent, since no studies were available for more than 90% of its countries. More research should be carried out to fill in the gaps identified by this review.