Prevalence and Serotype Diversity of in Apparently Healthy Cattle: Systematic Review and Meta-Analysis of Published Studies, 2000-2017.

Salmonellosis is a leading cause of foodborne illnesses in humans with cattle being one of the reservoirs for . We estimated a pooled prevalence of in apparently healthy cattle and examined serotype diversity through systematic review and meta-analysis of studies published between 2000 and 2017. Peer reviewed publications reporting the prevalence of in cattle were searched through five electronic databases (PubMed, Google scholar, Agricola, Scopus, CAB direct) and through manual search. We obtained 71 publications with 75 datasets consisting a total of 52,766 animals examined and 5,010 positive cattle from 29 countries in six continents (except from Antarctica). Pooled prevalence of in cattle was 9% (95% confidence interval: 7-11%). Significantly high heterogeneity ( = 98.7%, < 0.01) was observed among all studies as well as within continents. Prevalence varied from 2% (Europe) to 16% (North America). Overall, 143 different serotypes were reported with the most diverse serotypes being reported from Africa (76 different serotypes) followed by North America (49 serotypes). The 10 most frequently reported serotypes (Montevideo, Typhimurium, Kentucky, Meleagridis, Anatum, Cerro, Mbandaka, Muenster, Newport, and Senftenberg) accounted for 65% of the isolates for which specific serotype information was reported. Montevideo and . Dublin are the most frequently reported serotypes in North America and Europe, respectively, while . Typhimurium was the most frequent in Africa, Asia and Australasia. Our results indicated variability both in the prevalence and serotype diversity of in cattle across continents. Although all serotypes are potentially pathogenic to humans, five (Montevideo, Typhimurium, Anatum, Mbandaka, and Newport) of the top 10 serotypes identified in this study are among the serotypes most commonly associated with clinical illnesses in humans.