Anthelmintic resistance in livestock in Africa: review of the current status

Livestock across the globe are frequently infected with multiple gastrointestinal nematode species, and the use of anthelmintics remains a cornerstone of their control.

However, anthelmintic resistance poses a growing threat to sustainable livestock production, resulting in reduced productivity and compromised animal health and welfare.

Reports of resistance in various helminth species against multiple anthelmintic classes exist in African livestock.

Limited studies

Studies summarizing the extent and burden of this resistance are, however, limited, and systematic monitoring or surveillance efforts are largely absent across the continent.

For this reason, a research team led by scientists from the International Livestock Research Institute (ILRI) conducted a comprehensive scoping review to evaluate the current status of anthelmintic resistance in African livestock.

The study is published in BMC Veterinary Research (Oct 2025).

The systematic search yielded 357 original studies; 28 met the eligibility criteria, covering nine countries and spanning from 1996 to 2024.

All studies involved cattle and/or small ruminants, focusing primarily on two anthelmintic classes—benzimidazoles and macrocyclic lactones—and two gastrointestinal nematode genera: Haemonchus and Trichostrongylus.

Variable study methods

Resistance was reported across most of the studies, although reported prevalence rates were highly heterogeneous, varying considerably with anthelmintic class, livestock species, and geographic location.

The researchers observed variability in study methodologies, including differences in fecal egg count reduction test design, sampling intervals, dosage regimens, and reporting quality, which potentially limited comparability across countries and restricted epidemiological insight.

Need for surveillance

These findings highlight the urgent need to more accurately quantify the burden of anthelmintic resistance and to establish coordinated surveillance systems across Africa.

Equally important is the development of sustainable parasite control strategies and the promotion of responsible anthelmintic use to preserve the efficacy of existing drugs.

Citation

Gatitu, L., Kasudi, M.R., Githigia, S., Moodley, A. and Muloi, D. 2025. Anthelmintic resistance in livestock in Africa: review of the current status. BMC Veterinary Research 21: 615.

Photo: Milking line of cattle in Senegal (credit: ILRI/Karen Marshall)

Curated by Tezira Lore, Communication Officer, ILRI