Pakpoom Tadee

Occurrence and characterization of livestock-associated methicillin-resistant Staphylococcus aureus in pig industries of northern Thailand.

This study was conducted to determine the prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in pigs, farm workers, and the environment in northern Thailand, and to assess LA-MRSA isolate phenotypic characteristics. One hundred and four pig farms were randomly selected from the 21,152 in Chiang Mai and Lamphun provinces in 2012. Nasal and skin swab samples were collected from pigs and farm workers. Environmental swabs (pig stable floor, faucet, and feeder) were also collected. MRSA was identified by conventional bacterial culture technique, with results confirmed by multiplex PCR and multi locus sequence typing (MLST). Herd prevalence of MRSA was 9.61% (10 of 104 farms). Among pigs, workers, and farm environments, prevalence was 0.68% (two of 292 samples), 2.53% (seven of 276 samples), and 1.28% (four of 312 samples), respectively. Thirteen MRSA isolates (seven from workers, four from environmental samples, and two from pigs) were identified as Staphylococcal chromosomal cassette mec IV sequences type 9. Antimicrobial sensitivity tests found 100% of the MRSA isolates resistant to clindamycin, oxytetracycline, and tetracycline, while 100% were susceptible to cloxacillin and vancomycin. All possessed a multidrug-resistant phenotype. This is the first evidence of an LA-MRSA interrelationship among pigs, workers, and the farm environment in Thailand.

Comparative Phenotypic and Genotypic Characterization of Salmonella spp. in Pig Farms and Slaughterhouses in Two Provinces in Northern Thailand

Salmonella spp. are an important group of bacterial zoonotic pathogens which can cause acute food-borne diseases in humans. Pork products are the main source of salmonellosis, but the origins and transmission routes of the disease have not been clearly determined. The purpose of this study was to characterize Salmonella spp. isolated in pig production lines both from pig farms and from slaughterhouses in Chiang Mai and Lamphun provinces in northern Thailand. The study focuses on the association among serotypes, antimicrobial resistance patterns and Pulse Field Gel Electrophoresis (PFGE) patterns to investigate possible sources of infection and to provide information which could help strengthen salmonellosis control programs in the region. A total of 86 strains of Salmonella comprising five majority serotypes were identified. Antibiotic resistance to tetracycline was found to be the most prevalent (82.56%) followed by ampicillin (81.40%) and streptomycin (63.95%). Seven clusters and 28 fingerprint-patterns generated by PFGE were identified among strains recovered from various locations and at different times, providing information on associations among the strains as well as evidence of the existence of persistent strains in some areas. Study results suggest that Salmonella control programs should be implemented at slaughterhouse production lines, including surveillance to insure good hygiene practices, in addition to regular monitoring of large populations of farm animals.

Distribution, quantitative load and characterization of Salmonella associated with swine farms in upper-northern Thailand.

This study was conducted to analyze the prevalence and quantitative loads of Salmonella spp. on pig farms in Chiang Mai, Lamphun, Thailand to assess loading levels before slaughtering. The serotype diversity, antimicrobial-resistance pattern and pulse-field type of Salmonella spp. were also characterized to assess the dynamic propagation of the pathogen. The Salmonella-positive prevalence was 246/805 (30.56%), and the quantitative loads varied from 1.48~4.04 Log10MPN/g, with a mean ± standard deviation of 2.11 ± 0.57. AMP/S/TE (ampicillin/streptomycin/tetracycline) was the highest frequency antimicrobial resistance pattern found in this study. In addition, Salmonella Rissen was the primary serotype in this region. PFGE results indicated the occurrence of infection by cross contamination among pig farms. Our study showed that pork is easily contaminated with this pathogen. Farm control programs must be based on strict biosecurity and hygienic measures, which could further reduce the contamination pressure at slaughterhouses or retail shops.

An integrative approach to enhancing small-scale poultry slaughterhouses by addressing regulations and food safety in northern -Thailand

BackgroundIn Asian countries, small-scale rural poultry meat production can face challenges due to food safety policies that limit economic growth and hinder improvement of sanitation and disease prevention. In this study, an integrative, participatory research approach was used to elucidate the sanitation and disease prevention practices in small-scale poultry slaughterhouses in rural northern Thailand.MethodsInitial steps included the identification of key stakeholders associated with the meat production chain, development of a research framework, and design of a methodology based on stakeholder consultations. The framework and methodology combine issues in five major areas: (1) public health, (2) socioeconomics, (3) policy, (4) veterinary medicine, and (5) communities and the environment. Methods used include questionnaires, direct observation, focus groups, and in-depth interviews. In addition, a microbiological risk assessment approach was employed to detect Salmonella contamination in meat processing facilities. The microbial risk assessment was combined with stakeholder perceptions to provide an overview of the existing situation, as well as to identify opportunities for upgrading slaughterhouses in order to more effectively address matters of food safety, processing, and government licensing.ResultsThe conceptual framework developed elucidated the complex factors limiting small-scale slaughterhouse improvement including a lack of appropriate enabling policies and an apparent absence of feasible interventions for improvement. Unhygienic slaughterhouse management was reflected in the incidence of Salmonella contamination in both the meat and the surrounding environment.ConclusionThere is potential for the use of an integrative approach to address critical problems at the interface of rural development and public health. The findings of this study could serve as a model for transdisciplinary studies and interventions related to other similar complex challenges.