DISTRIBUTION OF ENTOMOPATHOGENIC NEMATODES IN LOWER NORTHERN THAILAND.

Entomopathogenic nematodes (EPNs) are used successfully for biological control of subterranean larval pests leading to reduced environmental contamination if chemical control measures are employed. Their diversity and distribution in Thailand are unclear, so the present study sought to obtain a better understanding these EPN populations in the lower northern region of Thailand. We collected 930 soil samples from 186 sites of Kamphaeng Phet, Nakhon Sawan, Phetchabun, Phichit, Phitsanulok, Sukhothai, Tak, Uthai Thani, and Uttaradit Provinces, Thailand from December 2011 to November 2012. Galleria mellonella was used as host for isolating and propagating EPNs. Seventy soil samples (7.5%) yielded EPNs of two genera, Steinernema (3.0%) and Heterorhabditis (4.5%). The majority of the isolated EPNs were found in loam at 26°C-33°C and pH values of 5.0-7.0. Molecular identification from partial 28S rDNA sequences revealed S. websteri, isolated from soil samples from Nakhon Sawan and Uthai Thani. Phylogenetic analysis of these EPNs showed they are closely related to S. websteri JC1032. The identification that S. websteri was the predominant EPN should enable its application for biological control in the local prevailing soil conditions.

Distribution among Thai children of methicillin-resistant Staphylococcus aureus lacking cna, fnbA and icaAD.

Staphylococcus aureus is a bacterium causing infections in both community and hospitals. S. aureus nasal colonization increases the risk of acquiring S. aureus infection. In this study, the prevalence of S. aureus nasal colonization was determined in Thai children, showing that nasal colonization was found in 78 of 217 subjects and the methicillin-resistant S. aureus (MRSA) carriage rate was present in 5 of 217 children. Among 78 S. aureus isolates, resistance to penicillin, erythromycin, clindamycin, chloramphenicol, trimethoprim/sulfamethoxazole, oxacillin and cefoxitin was found in 99%, 8%, 1%, 4%, 1%, 8% and 6% of the isolates, respectively. The presence of 3 adhesin genes, investigated by PCR, revealed that among 78 isolates, fnbA, icaAD and cna was detected in 73, 72 and 48 isolates, respectively but not in the 5 MRSA isolates. Ninety-five percent and 31% of S. aureus isolates were able to form strong and weak biofilms, respectively. Four MRSA isolates that lacked icaAD were non-biofilm-forming strains. These results revealed a high prevalence of S. aureus nasal colonization in healthy Thai children with 2% being MRSA. Effective strategies to prevent S. aureus transmission and infection are therefore needed in the Thai community.