title: Seroprevalence and risk factors of Mycoplasma suis infection in pig farms in central China.
abstract: Mycoplasma suis, the causative agent of porcine infectious anemia, causes large economic losses to the swine industry worldwide. A questionnaire-based survey was conducted in 69 pig farms in Hubei Province, China, from November 2011 to August 2013 to ascertain the prevalence and associated risk factors of M. suis. Four thousand and four blood samples from pigs of all the age groups were tested for M. suis antibodies using the established rMSG1-ELISA assay. Among these 4004 samples, 1615 blood samples from multiparous sows were examined to identify the association between seroprevalence and different seasons. Information on risk factors collected from farmers or attending veterinarians was recorded on a pre-designed questionnaire. The overall test seroprevalence of M. suis infection at the animal level was 31.9% (1277/4004; 95% CI: 30.5%, 33.4%), whereas at the farm level, this value was 95.65% (66/69; 95% CI: 87.8%, 99.1%). The seroprevalence of M. suis was higher in replacement gilts (40.6%; 95% CI: 35.1%, 46.3%), multiparous sows (48.2%; 95% CI: 45.8%, 50.7%) and boars (44.4%; 95% CI: 34.5%, 54.8%), as compared to piglets (13.0%; 95% CI: 9.4%, 17.3%), weaned-piglets (10.8%; 95% CI: 8.9%, 13.0%), and growing-finishing pigs (25.0%; 95% CI: 22.0%, 28.3%). In terms of seasons, the prevalence of M. suis in pigs was significantly higher in summer (65.3%; 95% CI: 61.0%, 69.5%) and autumn (65.0%; 95% CI: 59.0%, 70.6%) compared to spring (30.1%; 95% CI: 26.0%, 34.4%) and winter (36.4%; 95% CI: 31.4%, 41.5%). Farm-level risk factors were identified by multivariable logistic regression analysis. The associated factors retained in the final multivariable logistic regression model were drug treatment, presence of mosquitoes and flies, and frequency of disinfection. Drug treatment (OR=0.24; 95% CI: 0.07, 0.88; P=0.031) and frequency of disinfection (OR=0.23; 95% CI: 0.06, 0.90; P=0.035) were protective factors, and the presence of mosquitoes and flies (OR=5.994; 95% CI: 1.56, 23.00; P=0.009) was a risk factor for M. suis infection on farms. The results of the present study provide the first insight into the impact of associated determinants on M. suis infection in central China.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Qiqi
authors.initials: Q
authors.lastname: Song
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Weijing
authors.initials: W
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Weijiao
authors.initials: W
authors.lastname: Song
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Zehua
authors.initials: Z
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Muhammad Kasib
authors.initials: MK
authors.lastname: Khan
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Lan
authors.initials: L
authors.lastname: He
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Rui
authors.initials: R
authors.lastname: Fang
authors.affiliation: Department of Nosocomial Infection, Henan Provincial People's Hospital, Zhengzhou 450000, Henan, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Yanqin
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
authors.forename: Min
authors.initials: M
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Key Laboratory of Animal Epidemical Disease and Infectious Zoonoses, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China. Electronic address: zhaojunlong@mail.hzau.edu.cn.
authors.forename: Junlong
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002681:China / Q000453:epidemiology; D003625:Data Collection; D005260:Female; D008297:Male; D009174:Mycoplasma / Q000145:classification*; D009175:Mycoplasma Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D009792:Oceans and Seas; D016017:Odds Ratio; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D011795:Surveys and Questionnaires; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000382:microbiology*
keywords: Central China; Mycoplasma suis; Pigs; Risk factors; Seroprevalence