Feline strongyloidiasis: An insight into its global prevalence and transmission cycle

Abstract

The potential cross-transmission of Strongyloides stercoralis between dogs and humans has become an increasing focus of strongyloidiasis research and control programs. However, the role of cats and wild felids in the maintenance and transmission cycles of human and canine strongyloidiasis has received sparse attention. Feline strongyloidiasis epidemiology remain enigmatic. We conducted a systematic review and meta-analysis to assess the global prevalence of Strongyloides spp. in felines and reviewed cross-species infection studies to elucidate the transmission cycle of some feline Strongyloides species. Literature searched from seven databases identified 42 eligible prevalence studies published between 1985 and 2024. Of these, 44 datasets from 40 studies were included in the meta-analysis. Using a random effect model combined with the Rogan-Gladen method, we estimated the pooled global prevalence of Strongyloides spp. in felines at 13.3% (95% CI: 8.3–18.3%), with rates of 12.2% (95% CI: 6.7–17.8%) in domestic cats (Felis catus) and 20.0% (95% CI: 14.9–25.2%) in wild felids. Feline strongyloidiasis was distributed across all six WHO regions, with Africa (49.7%; 95% CI: 40.0–59.3%) and the Western Pacific (46.9%; 95% CI: 42.6–51.1%) showing the highest pooled prevalence. Subgroup analysis revealed a significantly higher prevalence of Strongyloides infection in stray domestic cats (29.2%; 95% CI: 6.3–52.1%) compared to pet cats (9.3%; 95% CI: 3.7–14.9) and shelter cats (4.4; 95% CI: 0–9.0). Historical cross-species transmission studies demonstrated variable susceptibility of cats to human- or canine-derived S. stercoralis. It remains inconclusive whether cats act as a reservoir for S. stercoralis infection in humans or vice versa. Feline strongyloidiasis is a prevalent condition in wild, stray, pet and shelter cats. Much of the available prevalence data does not discriminate to species level, and the role of cross-species transmission in feline S. stercoralis infections remains obscure. Future studies would benefit from utilising molecular genotyping tools to enable species-level phylogenetic differentiation.