A systematic review and meta-analysis of canine, feline and human Toxocara infections in sub-Saharan Africa

J Helminthol. 2019 Nov 4:94:e96. doi: 10.1017/S0022149X19000889.

Abstract

Toxocariasis is an emerging zoonotic disease caused by Toxocara canis and T. cati. Toxocariasis and its etiological agents are of global public health importance, whose burden appears underestimated, especially in sub-Saharan Africa (SSA). The diversity in the transmission routes of these parasites contributes to disease prevalence and often hinders disease control measures. This study aimed to review the epidemiological distribution of Toxocara infections in SSA region. A systematic review and meta-analysis were performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). We identified 94 relevant, peer-reviewed articles, out of which, 75 articles were found eligible based on Toxocara infections in dogs, cats and humans. Overall, 27,102 samples were examined for T. canis in dogs, T. cati in cats and Toxocara serology in humans, out of which 6142 were positive for Toxocara infection: 3717 (13.7%) in dogs (faecal, 3487; necropsy, 180; hair, 50); 266 (1%) in cats (faecal, 101; necropsy, 165); and 2159 (8%) in humans (serology). Overall mean prevalences of 19% (95% confidence interval (CI): 14-23%), 9% (95% CI: 0-28%) and 36% (95% CI: 24-49%) were recorded in dogs, cats and humans, respectively. Substantial heterogeneity was observed between studies and subgroups (I2 = 99%, P < 0.01). Findings from the review showed that studies on the epidemiology of Toxocara infections in the SSA region are limited. We strongly recommend focused, collaborative and coordinated studies to determine Toxocara spp. prevalence in various hosts, including food animals and the environment, through a 'One Health' approach across SSA countries.

Keywords: Prevalence; Toxocara infections; meta-analysis; review; risk factors; sub-Saharan Africa; zoonosis.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Africa South of the Sahara / epidemiology
  • Animals
  • Cat Diseases / epidemiology
  • Cat Diseases / parasitology*
  • Cat Diseases / transmission
  • Cats
  • Dog Diseases / epidemiology
  • Dog Diseases / parasitology*
  • Dog Diseases / transmission
  • Dogs
  • Feces / parasitology
  • Humans
  • Toxocara / classification
  • Toxocara / genetics
  • Toxocara / isolation & purification
  • Toxocara / physiology
  • Toxocariasis / epidemiology
  • Toxocariasis / parasitology*
  • Toxocariasis / transmission
  • Zoonoses / parasitology