Prevalence of Parasitic Infections with Zoonotic Potential in Tilapia: A Systematic Review and Meta-Analysis

Simple Summary The consumption of fish represents a healthy and affordable alternative for a large sector of the population; among the species with the highest consumption worldwide are tilapia. However, its consumption may be associated with health risks of a parasitic type. Through the analysis of the available scientific literature on parasitic prevalence in tilapia, it was observed that fish obtained from the wild and aquaculture represent a risk of parasitosis in human populations. Additionally, a high prevalence of cestodes and a greater diversity of trematodes were found. Finally, the presence of the genus Gnathostoma must stand out. This synthesis of information can be useful as a platform for the develCopment of intervention programs for parasite control, and it also suggests continuing with the study of zoonotic parasites related to the consumption of tilapia in geographical areas of high consumption. Tilapia has a high socioeconomic value in many countries worldwide. However, it has been identified as a zoonotic parasite reservoir. A systematic literature search and meta-analysis were carried out in order to estimate the global prevalence of zoonotic parasites that affect tilapia. The search was performed by three field experts to avoid reviewer bias. Polled prevalence was estimated using a logistic-normal random-effect regression model in the R software. We dealt with the heterogeneity among studies through subgroup analysis, taking into account the continent, country, genus of the host, parasite taxonomic group, sample origin, and type of diagnostic test as moderator variables. Fifty-two eligible articles were identified covering five tilapia genera with a pooled prevalence of 0.14 (95% CI: 0.10-0.20) showed significant heterogeneity (I-2 = 98.4; p < 0.001). The subgroup analysis revealed that the most affected host was Sarotherodon, with a prevalence of 0.42 (95% CI: 0.22-0.65). Cestode was the taxonomic group with the largest prevalence (0.40; 95% CI:0.32-0.48), followed by amoeba (0.24; 95% CI: 0.16-0.35) and nematode (0.22; 95% CI: 0.11-0.38), among which, Schyzocotyle spp., Opistorchis spp., Gnathostoma spp. and Vermamoeba spp. have an impact on public health. Significant differences (p < 0.004) were found among continents and countries, with the highest value of prevalence detected in the African continent (0.28; 95% CI: 0.20-0.37), specifically in Tanzania (0.56; 95% CI: 0.22-0.87) and Egypt (0.43; 95% CI: 0.20-0.55). The origin of samples had a significant effect (p < 0.0001) on the detected prevalence, especially from those that showed the highest prevalence (0.24; 95% CI: 0.17-0.33). Finally, there were no differences in prevalence according to the diagnostic test (p = 0.97). Our results provide useful information on the development of epidemiological programs for the control of zoonoses associated with parasites in tilapia and in the design, planning, and implementation of future research.