Horses in southwestern China are a potential source of human infections caused by the diarrhoea-causing parasitic fungus Enterocytozoon bieneusi, researchers report.
E. bieneusi is one of the most common microsporidian species − parasitic fungi capable of causing gastroenteritis in vertebrates and invertebrates.
It is one of most common pathogens that cause diarrhea and gut diseases across a range of hosts. It has been identified in humans, mammals, birds, rodents and reptiles in China, but few studies have reported it in horses.
Sichuan Agricultural University researchers Lei Deng, Wei Li, Zhijun Zhong, and their colleagues set out to learn more about E. bieneusi in horses in southwestern China.
A total of 333 fecal specimens were collected from horses on five farms in the Sichuan and Yunnan provinces.
The study team undertook molecular testing for genetic material in the fungi, determining that E. bieneusi was present in 22.5% of the samples – that’s 75 of the 333 animals.
The researchers noted that the prevalence in horses over 3 years of age was higher (25.0%) than that in horses aged under a year (17.1%).
Altogether, 10 genotypes were identified among the 75 positive samples. Four of these genotypes were already known – horse1, horse2, SC02 and D. However, six were novel – SCH1, SCH2, SCH3, SCH4, YNH1 and YNH2.
The study team, writing in the journal Parasites & Vectors, said the presence of genotype D, which was previously identified in humans, and genotypes SC02 and SCH1, 2 and 3, which belong to a potentially zoonotic grouping, indicate that horses are a potential source of human E. bieneusi infections in China.
“Since the specific routes of transmission of E. bieneusi remain unknown and there are no effective drugs for the complete treatment of E. bieneusi infection in humans or animals, farm managers should be advised to take measures to control environmental contamination,” they wrote.
Molecular characterization and multilocus genotypes of Enterocytozoon bieneusi among horses in southwestern China
Lei Deng, Wei Li, Zhijun Zhong, Chao Gong, Xuehan Liu, Xiangming Huang, Li Xiao, Ruoxuan Zhao, Wuyou Wang, Fan Feng, Yue Zhang, Yanchun Hu, Hualin Fu, Min He, Yue Zhang, Kongju Wu and Guangneng Peng
Parasites & Vectors 2016 9:561 DOI: 10.1186/s13071-016-1844-3