| dc.description.abstract | Introduction: Livestock abortigenic agents, which are microorganisms that lead to
premature foetal death and expulsion before completion of the gestation period, are common in
Africa and Asia. Abortion events cause economic losses by lowering reproduction (and hence
herd/flock sizes) and effects on milk production. Despite the importance of livestock production for
food security and livelihoods of millions of the world’s poorest communities, very little is known
about the scale, magnitude or causes of livestock abortion in Africa. The aim of this review was to
determine the current status of the burden of livestock abortion and surveillance measures adopted
for livestock abortigenic pathogens in Africa and Asia, and to explore feasible surveillance
technologies. Methodology: A systematic literature search was conducted using Preferred
Reporting of Systematic Reviews and Meta-analyses (PRISMA) guidelines in four databases for
studies published between 1 Jan 1990 and 31 July 2021 that reported epidemiological surveys of
livestock abortigenic pathogens in cattle, goats and sheep in Africa and Asia including; Brucella spp.,
Neospora caninum, Toxoplasma gondii, Rift valley fever virus, Coxiella burnetii, Chlamydia, Leptospira and
Bovine viral Diarrhoea Virus. A meta-analysis was used to estimate the species-specific prevalence of
the abortigenic diseases and the region where they were detected. Results: In the systematic
literature search, 48 full papers were included which in total included 50 species-specific
surveillance reports from Africa and 19 from Asia. Adjusted median seroprevalence calculations
estimated Brucella at 6.85% (range 1.2-11.6) of 9071 sheep, 3.35% (range 0.90-5.40) of 17,007 goats,
8.95% (range 0.50-63.60) of 171,733 cattle, Neospora at 6.80% (range 6.80 -6.80) of 555 sheep, 10.80
(range 10.80-10.80) of 185 goats, 12.65% (range 3.40- 25.60) of 3775 cattle, Toxoplasma at 27.50% (range
1.40 – 75.90) of 2284 sheep, 32.0% (range 20.00- 64.80) of 1226 goats, 7.50% (range 7.50 - 7.50) of 174
cattle, Coxiella at 9.20 (range 9.20 – 9.20) of 184 sheep, 24.20% (range 24.20-24.20) of 91 goats, 13.80%
(range 13.80-13.80) of 217 cattle, Rift valley fever virus at 7.70 (2.40-40.00) of 874 sheep, 20.95 (range
2.50-40.00) of 547 goats, 7.45% (range 3.60-11.30) of 309 cattle, Bovine viral diarrhea virus at 78.90
(range 78.90 – 78.90) of 398 cattle, Leptospira at 70.50 (range 70.50 – 70.50) of 373 cattle and
Chlamydia at 6.60 (6.60-6.60) of 803 sheep. We found that most studies, 45 (89%) used serological
surveys, 1 (2%) used molecular and 1 (2%) reported to have used Mobile-phone based surveillance
approach. Three studies (6.25%) of the 48 included were embedded in the national surveillance
programs of the respective countries they were conducted, majority 89% were stand-alone cross-
sectional studies. Conclusion :In conclusion, livestock abortigenic pathogens are still a burden in
many African and Asian countries. | en_US |
