The selling and importing of puffer fish species and their products was banned in Thailand in 2002, because of possible neurotoxic effects. However, the sale of their flesh is still happening in Thai markets. Standard methods for toxin quantification (HPLC and LC-MS) have significant limitations, therefore a lateral flow, immuno-chromatographic test (TTX-IC) was developed as a tool for rapid detection of toxin. A total of 750 puffer fishes (387 Lagocephalus lunaris(LL), and 363 Lagocephalus spadiceus (LS)) and 100 edible fishes were caught in Thailand from June 2011-February 2012. Screening of TTX from their flesh by TTX-IC revealed that 69 samples (17.8%) of LL possessed TTX at dangerous levels but LS and edible fishes did not. A selected 339 samples were quantified by LC-MS/MS, showing 50 LL possessed TTX at dangerous levels. Comparison of results with LC-MS/MS showed the TTX-IC to have 94.0% sensitivity and 92.4% specificity. The TTX-IC will be a useful tool for TTX screening of a large number of samples, reducing the testing required by LC-MS/MS, thus reducing costs. All positive cases found should be confirmed by standard methods.

This study demonstrated the potential application of antibody-conjugated Rubpy dye-doped silica nanoparticles for immunofluorescence microscopic detection ofVibrio choleraeO1. The particle synthesis of 20X of the original ratio was accomplished yielding spherical nanoparticles with an average size of45±3 nm. The nanoparticles were carboxyl functionalized and then conjugated with either monoclonal antibody or polyclonal antibody againstV. choleraeO1. The antibody-conjugated nanoparticles were tested with two target bacteria and three challenge strains. The result showed that monoclonal antibody-conjugated Rubpy dye-doped silica nanoparticles could be effectively used as signal amplification to detectV. choleraeO1 under a fluorescence microscope. Their extremely strong fluorescence signal also enables the detection of a single cell bacterium.

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This paper describes an application of Rubpy dye-doped silica nanoparticles (RSNPs) as signal reporter in a dot fluorescence immunoassay strip for rapid screening ofVibrio choleraO1 (VCO1). These nanoparticles have a spherical shape with an average diameter of 45 nm. They appear luminescent orange when excited with a 312 nm UV lamp. Based on the sandwich immunoassay principle, a test strip was made of a nitrocellulose membrane dotted with monoclonal antibodies against VCO1 as analyte capture molecules. After introducing a test sample, followed by polyclonal rabbit anti-VCO1 antibody conjugated RSNPs as detection reporters and one washing step, the presence or absence of the target bacteria could be identified under UV light by naked eyes. A positive sample would signal a bright orange dot on the strip. The proposed assay had a detection limit of4.3×103 cfu/mL and was successfully applied as a rapid screening test for VCO1 in food samples with high sensitivity, specificity, and accuracy.

Introduction-Thailand conducted a national laboratory assessment of core capacities related to the International Health Regulations (IHR) (2005), and thereby established a baseline to measure future progress. The assessment was limited to public laboratories found within the Thai Bureau of Quality and Safety of Food, National Institute of Health and regional medical science centres.

Of SO patients in Thailand suspected clinically of having exanthem subiturn, 31 (62%) were serodiagnosed as HHV-6 infection. Sixteen strains of HHV-6 from 31 patients (52%) whose antibody titers had converted during convalescence were isolated during the acute phase. The disease occurred in infants from 3 months to 1 year of age and most frequently at age 4-6 months. Antibody only to HHVB converted in 23 of SO patients (46%), and seroconversion to HHV-6 and dengue virus was observed in 7 patients (14%), and to HHV-6 and Coxsackie B virus in 1 case (2%). In the 23 patients in whom seroconversion only to HHV-6 was observed, all had fever and rash which appeared after subsidence of the fever. Lymphadenopathy and relative lymphocytosis were recognized, associated with diarrhea, vomiting, running nose, cough and hepatomegaly. Febrile convulsions were seen in some cases. All patients recovered completely within a week.