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The prevalence of Non-typhoidal Salmonella (NTS) and extended-spectrum ß-lactamase (ESBL) producing bacteria was assessed in samples of imported prawn and shrimp obtained from retail markets in Japan. The overall prevalence of NTS and ESBL producing bacteria was 4%, and 14%, respectively. We identified 4 NTS isolates, including S. enterica subspecies salamae, and 3 serovars of S. enterica subspecies enterica, including Weltevreden, Abony, and Stanley. ESBL producing bacteria were isolated from 14 of 100 samples, thirteen of which harbored Stenotrophomonas maltophilia and that harbored Chryseobacterium indologenes. Among the S. maltophilia-positive samples, six had been imported from India, five samples came from Indonesia, one sample was from Thailand, and 1 was from Vietnam. These 14 ESBL isolates were susceptible to moxalactam, chloramphenicol, nalidixic acid, ofloxacin, and sulfamethoxazoletrimethoprim; however, all isolates were resistant to carbapenems. These findings indicate that to increase food safety, information regarding contamination by foodborne pathogens including Salmonella should be provided as feedback to the food's country of origin. Additionally, more detailed studies regarding the epidemiological significance of S. maltophilia and C. indologenes contamination of imported food are needed for both food-exporting and -importing countries. [ABSTRACT FROM AUTHOR]

More than 30 species of bartonellae that are highly prevalent in a wide variety of vertebrates have been described. Bartonella bacilliformis, B. henselae, and B. quintana are well-known human pathogens, [...]

A study was conducted to determine the prevalence of Campylobacter with antimicrobial resistance from chickens, pigs, dairy cows, healthy farm workers, and children hospitalized with diarrhea in northern Thailand. Resistance was highest in pig samples and lowest in healthy farm workers. Resistance to fluoroquinolones and tetracycline was high in all study populations. The increased prevalence of resistant isolates from meat samples collected at markets, compared to isolates collected from animals on the farm or the slaughterhouse, suggests that contamination after carcasses leave the slaughterhouse is an important factor in the spread of resistant bacteria into the human food chain. [ABSTRACT FROM AUTHOR]

We identified Bartonella vinsonii subsp. arupensis in pre-enriched blood of 4 patients from Thailand. Nucleotide sequences for transfer-messenger RNA gene, citrate synthase gene, and the 16S-23S rRNA internal transcribed spacer were identical or closely related to those for the strain that has been considered pathogenic since initially isolated from a human in Wyoming, USA. [ABSTRACT FROM AUTHOR]

Bartonella bovis is commonly detected in cattle. One B. bovis strain was recently isolated from a cow with endocarditis in the USA, suggesting its role as an animal pathogen. In the present study, we investigated bartonella infections in 893 cattle from five countries (Kenya, Thailand, Japan, Georgia, and Guatemala) and 103 water buffaloes from Thailand to compare the prevalence of the infection among different regions and different bovid hosts. We developed a multi-locus sequence typing (MLST) scheme based on nine loci (16S rRNA, gltA, ftsZ, groEL, nuoG, ribC, rpoB, ssrA, and ITS) to compare genetic divergence of B. bovis strains, including 26 representatives from the present study and two previously described reference strains (one from French cows and another from a cow with endocarditis in the USA). Bartonella bacteria were cultured in 6.8% (7/103) of water buffaloes from Thailand; all were B. bovis. The prevalence of bartonella infections in cattle varied tremendously across the investigated regions. In Japan, Kenya, and the Mestia district of Georgia, cattle were free from the infection; in Thailand, Guatemala, and the Dusheti and Marneuli districts of Georgia, cattle were infected with prevalences of 10–90%. The Bartonella isolates from cattle belonged to three species: B. bovis (n=165), B. chomelii (n=9), and B. schoenbuchensis (n=1), with the latter two species found in Georgia only. MLST analysis suggested genetic variations among the 28 analyzed B. bovis strains, which fall into 3 lineages (I, II, and III). Lineages I and II were found in cattle while lineage III was restricted to water buffaloes. The majority of strains (17/28), together with the strain causing endocarditis in a cow in the USA, belonged to lineage I. Further investigations are needed to determine whether B. bovis causes disease in bovids. [ABSTRACT FROM AUTHOR]

A total of 138 isolates of S. Typhimurium and S. 4,[5],12:i:- from humans and swine in Thailand during 2003-2006, were evaluated for antimicrobial sensitivity by the disk diffusion method against 10 antimicrobial drugs and pulsed-field gel electrophoresis (PFGE) with endonuclease Xbal to investigate the epidemiological relationship among isolates. It was found that all isolates were classified into 27 antimicrobial resistance patterns, and 80% of S. Typhimurium and 95.4% of S. 4,[5],12:i:- isolates were resistant to three or more antimicrobial agents. By PFGE testing, the 84 PFGE patterns were categorized into A to Z patterns. Eighty percent of S. Typhimurium and 71.3% of S. 4,[5],12:i:- isolates in 7 major PFGE patterns had close clonal relationships (_85% similarity). Our studies indicate the spread of genetically identical clones of S. Typhimurium and S. 4,[5],12:i:- in humans and swine in Thailand.

In 2005, total of 140 samples of duck meat and intestine from slaughterhouses in Nakhon Pathom Province, Thailand, were analyzed for Campylobacter spp. Twenty-eight samples (20%) were positive for Campylobacter spp using the standard culture method (SCM) with 21 samples of C. jejuni and the other 7 C. coli. Forty-four samples (31%) were positive using multiplex polymerase chain reaction, with 34 samples of C. jejuni and 10 of C. coli. This is the first report of Campylobacter contamination in duck in Thailand.

In Thailand, 51% (36/70) Campylobacter jejuni isolates from humans and 68% (47/69) isolates from poultry were classified into 10 Penner serotypes (serotype B, C, R, E, G, A, K, D, I, and L) and 9 serotypes (serotype A, C, I, K, B, E, S, D, and L), respectively. The rate of antimicrobial drug resistance to nalidixic acid, ciprofloxacin, ampicillin, tetracycline, and erythromycin shown by human isolates were 96%, 96%, 29%, 57%, and 14%, while that shown by poultry isolates were 77%, 77%, 22%, 26%, and 17%, respectively. All quinolone-resistant strains contained a mutation in the gyrA gene (T(86)-->I(86)), suggesting that the strains were already widespread in Thailand.

From November 2004 to March 2005, 50 samples (chicken, pork and beef) of registered meat and non-registered meat were purchased from supermarkets and retail markets located in Bangkok, Thailand. Each sample was evaluated for Salmonella spp by a conventional method using combination of selective enrichment media (RV+MSRV) and compared with selective enrichment medium alone (DIASALM). Our study revealed the performance of RV+MSRV for the detection of Salmonella spp was significantly better than those of DIASALM alone since the recovery of Salmonella spp in both groups of meat was high using RV+MSRV, particularly in the registered meat. In addition, the recovery of serovars in registered meat was significantly higher than those in non-registered meat. Antimicrobial resistance of 62 Salmonella isolates in both groups of meat was determined for 10 antimicrobial drugs using the disk diffusion method. The results show that 100% of isolates from both groups were susceptible to amoxicillin/clavulanic acid, ciprofloxacin, cefotaxime and norfloxacin and 50-60% of isolates from both groups were resistant to tetracycline, streptomycin and ampicillin. Sixty percent of Salmonella isolates from meat showed multiresistance antimicrobial patterns.

We investigated the serotypes, distributions, and antimicrobial resistance of Campylobacter jejuni isolates from humans and animals as a source of infection in poultry between 2002 and 2003. A total of 50 C. jejuni isolates from humans and 29 C. jejuni isolates from poultry were studied for serotype using the Penner serotyping scheme and the drug susceptibilities of the isolates which were determined for 7 antimicrobial drugs using the disk diffusion method. Serotype B (10%), serotype E (8%) and serotype R (8%) were found in humans isolates, while serotype A (27%) was most freguently isolated from poultry, followed by serotype K (21%) and serotype C (13%). Resistance in human isolates to cephalothin was high (100%). Resistance to trimethoprim/sulfamethoxazole, ciprofloxacin, and nalidixic acid were observed in 90, 82 and 78% of isolates, respectively. Most of the isolates (88%) were susceptible to erythromycin. High levels of resistance to drugs (ciprofloxacin and nalidixic acid) were observed in the isolates from poultry. These results indicate the importance of poultry as a reservoir of C. jejuni infection in Thailand is limited. In addition, a high proportion of the isolates were resistant to antimicrobial drugs, particularly the quinolone group.