Cystic echinococcosis and Taenia spp. infections in Nigeria: A systematic review and meta-analysis of prevalence and geographical distribution

Abstract

Cystic echinococcosis (CE) and Taenia spp. infections are major zoonotic helminthiases with substantial public health and economic burdens, particularly in endemic regions. Despite their classification as neglected tropical diseases (NTDs), these tapeworm infections remain understudied in Nigeria. Accurate epidemiological data are essential for evidence-based control strategies, yet comprehensive estimates of their prevalence and geographical distribution in Nigeria are lacking. This systematic review and meta-analysis provide the first nationwide synthesis of CE and Taenia spp. infections in both human and animal populations, elucidating high-risk areas and guiding targeted interventions.

A comprehensive systematic search was conducted across four major databases (PubMed, Google Scholar, Africa Journal Online, and ScienceDirect) to identify relevant studies published between 1979 and October 2024. Eligible studies were selected based on predefined inclusion criteria and subjected to meta-analysis using RStudio (RStudio Team, 2024). Heterogeneity was evaluated using Cochran’s Q test and the I² statistic, while publication bias was assessed through the Luis Furuya-Kanamori (LFK) index, funnel plot asymmetry, and Egger’s regression test to ensure robustness of the findings.

The study compiled 156 datasets from 80 publications, primarily abattoir surveys. Of 86 reports on cystic echinococcosis (CE) in animals, half were from the Northwest. The South-South and North-Central regions had the most reports on Taenia infection (21.9% each). Post Mortem Examination and Microscopy (PME/MCS) were used in 76.5% of CE studies, while microscopy alone detected Taenia in 84.4% of cases. Among 5,542,336 hosts examined, 14,216 infections were identified, yielding an overall pooled prevalence of 0.26% (95% CI: 0.174–0.346%) likely an underestimate due to diagnostic limitations. Meta-analysis of CE in animals and human Taenia infections showed high variability (Q= 83,102.51; I²= 99.9%, P= 0.000), with individual study prevalence ranging from 0.00 to 27.91%. Human studies had weights of 2–3.5% (Q= 1003.05; I²= 96.9%, P<0.0001).

This study reveals a high prevalence of cestode infections, particularly in Northern Nigeria, emphasizing the persistent burden of these neglected diseases. Findings highlight critical gaps in surveillance, diagnostics, and species data, underscoring the urgent need for integrated One Health interventions and targeted public health strategies. Enhanced research and regular monitoring are essential for effective control.