title: Molecular detection and isolation of pathogenic Leptospira from asymptomatic humans, domestic animals and water sources in Nan province, a rural area of Thailand.
abstract: Leptospirosis is an important zoonotic disease that is often associated with animal carriers and contamination of the environment via infected urine. This study aimed to assess pathogenic leptospiral carriage in Nan province, a rural area of Thailand where leptospirosis is endemic. Samples from 20 villages were obtained during the period 2013 to 2016, comprising urine samples collected from asymptomatic people (n=37) and domestic animals (n=342), and environmental water samples (n=14). Leptospira were cultured in Ellinghauson McCullough Johnson and Harris (EMJH) media. An rrs nested PCR identified 9.92% (95% confidence interval (CI) 6.96-12.88) of the urine and water samples as being positive for Leptospira spp., and phylogenetic analysis was conducted on the 443bp amplicons. Leptospira weilii, which has not previously been identified in Thailand, was recovered from 13 cattle, 9 pigs, 2 dogs, 2 water samples and 1 goat. L. interrogans was found in 4 dogs, 3 pigs, 3 cattle, 1 human and 1 water sample. Four leptospiral strains were isolated and multilocus sequence typing (MLST) analysis was performed on these. Three novel sequence types were identified, including two singletons of L. interrogans in ST26 and ST33, and one of L. weilii in ST94, with this having a close relationship to previous isolates from cases of human leptospirosis in Laos and China. Our results revealed that pathogenic Leptospira occur commonly in asymptomatic domestic animals, humans and environmental water samples in Nan Province, and emphasize the high potential for zoonotic transmission in the province.
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Alongkorn
authors.initials: A
authors.lastname: Kurilung
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Pattrarat
authors.initials: P
authors.lastname: Chanchaithong
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Kittitat
authors.initials: K
authors.lastname: Lugsomya
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Waree
authors.initials: W
authors.lastname: Niyomtham
authors.affiliation: Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
authors.forename: Vanaporn
authors.initials: V
authors.lastname: Wuthiekanun
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand. Electronic address: Nuvee.P@chula.ac.th.
authors.forename: Nuvee
authors.initials: N
authors.lastname: Prapasarakul
mesh_terms: D000818:Animals; D000829:Animals, Domestic; D006801:Humans; D007919:Leptospira / Q000235:genetics / Q000302:isolation & purification*; D007922:Leptospirosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D013785:Thailand / Q000453:epidemiology; D014871:Water Microbiology; D015047:Zoonoses
keywords: Domestic animals; Leptospira weillii; Nan province; Pathogenic Leptospira; Thailand; Zoonosis