Prevalence, micro-morphology, and molecular validation of Giardia duodenalis assemblages among domestic dogs and their owners in urban informal settlements of Lusaka, Zambia

African Journal of Parasitology Research | Vol. 14, No. 8, August 2026 | pp. 653–660

DOI: 10.46882/AJPR/140653

Article Type: Full Length Research Paper

Title: Prevalence, micro-morphology, and molecular validation of Giardia duodenalis assemblages among domestic dogs and their owners in urban informal settlements of Lusaka, Zambia

Names of Authors: Chileshe K. Mwamba¹, Mwansa D. Chilufya¹, Josephine N. Banda²

Authors’ Affiliations: ¹School of Veterinary Medicine, University of Zambia, Lusaka, Zambia. ²School of Health Sciences, Department of Biomedical Sciences, University of Zambia, Lusaka, Zambia.

Abstract: Giardiasis is a widespread gastrointestinal infection with significant zoonotic potential where humans and domestic animals live in close proximity. This study evaluated the prevalence, cyst micro-morphology, and genetic assemblages of Giardia duodenalis in 420 domestic dogs and 210 matching owners in informal settlements around Lusaka, Zambia. Fecal samples were concentrated using zinc sulphate flotation and examined via light microscopy. Positive samples were further analyzed using nested PCR sequencing targeting the beta-giardin (bg) and glutamate dehydrogenase (gdh) genes. Microscopic screening revealed a Giardia prevalence of 24.3 percent (n = 102) in dogs and 11.4 percent (n = 24) in human participants. Molecular typing identified host-specific Assemblage C (54.8 percent) and Assemblage D (33.3 percent) as the dominant strains in dogs. However, the zoonotic Assemblage A was detected in 11.9 percent of infected dogs and 75.0 percent of infected human hosts. Identical Assemblage A nucleotide sequences were identified in three matching dog-owner pairs. Logistic regression associated zoonotic strain detection with keeping dogs indoors (odds ratio = 2.88, 95 percent confidence interval [1.44 to 5.76]) and poor household handwashing setups (odds ratio = 3.22, 95 percent confidence interval [1.81 to 5.72]). These findings show clear evidence of anthropozoonotic Giardia transmission, emphasizing that urban sanitation strategies should integrate veterinary health care alongside human hygiene interventions.

Keywords: Giardia duodenalis, Zoonotic assemblages, Beta-giardin, Companion animals, Urban slums, Zambia

Manuscript Timeline: Received: 10 June 2026; Revised: 05 July 2026; Accepted: 27 July 2026; Published: 22 August 2026

Subscribe to read the full article: https://internationalscholarsjournals.org/subscribe-to-read