Molecular Epidemiology of Giardia Species in Different Hosts in Africa: A Systematic Review and Meta-Analysis.

PURPOSE: Giardia duodenalis is a widespread flagellated protozoan parasite that infects the small intestines of many vertebrate hosts. The purpose of this study was to better understand the molecular epidemiology of G. duodenalis infections in Africa.

METHODS

The PRISMA for Systematic Reviews and Meta-Analyses criteria were used and five academic databases were searched for literature on the molecular detection of giardiasis in humans and animals in Africa. The study used a random-effects model and heterogeneity to estimate the pooled prevalence across studies that met the inclusion criteria. Fifty articles were included in the final analysis from a total of 1,121 identified articles.

RESULTS

The overall pooled molecular prevalence of giardia was higher in humans at 32.2% (95% CI: 24.8; 40.5) and lower in animals at 14.1% (95% CI: 0.9; 21.7). These studies have also identified variations in the distribution of Giardia duodenalis assemblages with Morocco having the highest pooled prevalence of assemblages A in human giardiasis (81.8%), while Mozambique had the lowest (8.2%). Similarly, Mozambique has the highest pooled prevalence of assemblage B (90.4%), whereas South Africa has the lowest (1.7%). Assemblage E, which appears in cattle, sheep, and goats, was the most common, with Rwanda having the lowest pooled prevalence (10%) and the Central African Republic having the highest (95.3%).

CONCLUSION

The high heterogeneity across all studies suggests these results should be used cautiously, however, the findings highlight the importance of ongoing research on G. duodenalis in humans and animals in order to inform public health policy and enhance management methods aimed at reducing zoonotic transmission.