African animal trypanosomiasis: a systematic review on prevalence, risk factors and drug resistance in sub-Saharan Africa

Okello, I. and Mafie, E. and Eastwood, G. and Nzalawahe, J. and Mboera, L. E. G.

Journal of Medical Entomology (2022) 59: 1099–1143

DOI: 10.1093/jme/tjac018

Abstract

African animal trypanosomiasis (AAT) a parasitic disease of livestock in sub-Saharan Africa causing tremendous loses. Sub-Saharan continental estimation of mean prevalence in both large and small domestic animals, risk factors, tsetse and non-tsetse prevalence and drug resistance is lacking. A review and meta-analysis was done to better comprehend changes in AAT prevalence and drug resistance. Publish/Perish software was used to search and extract peer-reviewed articles in Google scholar, PubMed and CrossRef. In addition, ResearchGate and African Journals Online (AJOL) were used. Screening and selection of articles from 2000-2021 was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Articles 304 were retrieved; on domestic animals 192, tsetse and non-tsetse vectors 44, risk factors 49 and trypanocidal drug resistance 30. Prevalence varied by, host animals in different countries, diagnostic methods and species of Trypanosoma. Cattle had the highest prevalence with Ethiopia and Nigeria leading, T. congolense (11.80-13.40%) and T. vivax (10.50-18.80%) being detected most. This was followed by camels and pigs. Common diagnostic method used was buffy coat microscopy. However; polymerase chain reaction (PCR), CATT and ELISA had higher detection rates. G. pallidipes caused most infections in Eastern regions while G. palpalis followed by G. mortisans in Western Africa. Eastern Africa reported more non-tsetse biting flies with Stomoxys leading. Common risk factors were, body conditions, breed type, age, sex and seasons. Ethiopia and Nigeria had the highest trypanocidal resistance 30.00-35.00% and highest AAT prevalence. Isometamidium and diminazene showed more resistance with T. congolense being most resistant species 11.00-83.00%.

Citation

Okello, I., Mafie, E., Eastwood, G., Nzalawahe, J., & Mboera, L. E. G. (2022). African animal trypanosomiasis: a systematic review on prevalence, risk factors and drug resistance in sub-Saharan Africa. Journal of Medical Entomology, 59(4), 1099–1143. https://doi.org/10.1093/jme/tjac018 Animals, Prevalence, techniques, systematic reviews, disease prevalence, epidemiology, literature reviews, drug resistance, disease vectors, domestic animals, hosts, infections, livestock, parasites, parasitoses, protozoal infections, risk factors, vectors, diagnosis, diagnostic techniques, detection, breeds, trypanosomiasis, ELISA, Africa South of the Sahara, vector-borne diseases, analytical methods, age, polymerase chain reaction, seasonality, antiprotozoal agents, Animal Shells, diminazene, geographical variation, isometamidium chloride, marine areas, microscopy, tsetsefly-borne diseases

Keywords

• Animals
• Prevalence
• techniques
• systematic reviews
• disease prevalence
• epidemiology
• literature reviews
• drug resistance
• disease vectors
• domestic animals
• hosts
• infections
• livestock
• parasites
• parasitoses
• protozoal infections
• risk factors
• vectors
• diagnosis
• diagnostic techniques
• detection
• breeds
• trypanosomiasis
• ELISA
• Africa South of the Sahara
• vector-borne diseases
• analytical methods
• age
• polymerase chain reaction
• seasonality
• antiprotozoal agents
• Animal Shells
• diminazene
• geographical variation
• isometamidium chloride
• marine areas
• microscopy
• tsetsefly-borne diseases