Prevalence and related factors of Enterocytozoon bieneusi in cattle: A global systematic review and meta-analysis

Enterocytozoon bieneusi (E. bieneusi) is an important zoonotic microsporidian pathogen that has a variety of hosts. Cattle are reservoir hosts of E. bieneusi, and play an important role in the epidemiology of E. bieneusi. However, no systematic research on the prevalence of E. bieneusi in cattle has been reported. Here, a systematic review and meta-analysis was performed to determine the prevalence of E. bieneusi in cattle. Six databases (PubMed, Web of Science, Springlink, Wanfang, CNKI, and VIP) were used for searching for relevant studies. The quantity of E. bieneusi infection in cattle was extracted and subjected to an estimation for the prevalence in cattle by using a random effects model. In total, forty articles from 12 countries were chosen from 524 studies from inception to 1st June 2021. An overall E. bieneusi prevalence (95% CI) in cattle was 12.9% (2566/19,791, 9.0–14.6%). The highest prevalence of E. bieneusi was 17.3% (13.9–20.3) in South America, and the lowest was 6.5% (4.1 – 9.4) in Africa 6.5%. The prevalence of E. bieneusi after 2016 (11.1%) was lower than 2016 and before (12.3%). Cattle aged 3–12 months had a higher prevalence (14.8%) as compared with cattle aged > 12 months (8.2%). The combined prevalence of E. bieneusi in the dairy cattle was 14.4%, which was higher than that in other species. In the subgroup of season, E. bieneusi prevalence in cattle was higher in spring (17.4%) and autumn (19.7%) than in summer (8.5%) and winter (8.5%). E. bieneusi prevalence in naturally grazed cattle was 3.6% and 13.7% in intensively fed cattle. A total of 83 E. bieneusi genotypes were prevalent in cattle, of which 15 genotypes found in the cattle had previously been found in humans. The global prevalence of E. bieneusi in cattle related to geographical and climate variables were evaluated as well. These data indicated that E. bieneusi was ubiquitous in cattle worldwide and carried a potential risk of infection in humans. Thus, the farm managers should provide a scientific mix of nutrients to improve cattle immunity, keep the environment clean, and disinfect regularly. Collectively, the control of E. bieneusi transmission in cattle is of importance for economic and public health.