สถาบันวิจัยวิทยาศาสตร์สาธารณสุข

National Institute of Health of Thailand

Authors : Piyada Wangroongsarb1, Tomoko Kohda2, Chutima Jittaprasartsin1, Karun Suthivarakom1, Thanitchi Kamthalang1, Kaoru Umeda3, Pathom Sawanpanyalert4, Shunji Kozaki2, Kazuyoshi Ikuta5*

 

Affiliations : 

1 Department of Medical Sciences, National Institute of Health, Nonthaburi, Thailand,
2 Department of Veterinary Science, Osaka Prefecture University, Osaka, Japan,
3 Department of Microbiology, Osaka City Institute of Public Health and Environmental Sciences, Osaka, Japan,
4 Department of Medical Sciences, Nonthaburi, Thailand,
5 Department of Virology, Osaka University, Osaka, Japan

 

Source :

PLOS ONE; January 2014: Vol.9 : Issue 1: e77792

 

Language :

English

 

Abstract :

 
 

Background: Thailand has had several foodborne outbreaks of botulism, one of the biggest being in 2006 when laboratory investigations identified the etiologic agent as Clostridium botulinum type A. Identification of the etiologic agent from outbreak samples is laborious using conventional microbiological methods and the neurotoxin mouse bioassay. Advances in molecular techniques have added enormous information regarding the etiology of outbreaks and characterization of isolates. We applied these methods in three outbreaks of botulism in Thailand in 2010.


Methodology/Principal Findings: A total of 19 cases were involved (seven each in Lampang and Saraburi and five in Maehongson provinces). The first outbreak in Lampang province in April 2010 was associated with C. botulinum type F, which was detected by conventional methods. Outbreaks in Saraburi and Maehongson provinces occurred in May and December were due to C. botulinum type A1(B) and B that were identified by conventional methods and molecular techniques, respectively. The result of phylogenetic sequence analysis showed that C. botulinum type A1(B) strain Saraburi 2010 was close to strain Iwate 2007.

Molecular analysis of the third outbreak in Maehongson province showed C. botulinum type B8, which was different from B1–B7 subtype. The nontoxic component genes of strain Maehongson 2010 revealed that ha33, ha17 and botR genes were close to strain Okra (B1) while ha70 and ntnh genes were close to strain 111 (B2).


Conclusion/Significance: This study demonstrates the utility of molecular genotyping of C. botulinum and how it contributes to our understanding the epidemiology and variation of boNT gene. Thus, the recent botulism outbreaks in Thailand were induced by various C. botulinum types.

 

 

Link :

PLOS One : http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0077792
NCBI : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3903786/