FIRST REPORT OF ISOLATION OF VIBRIO PARAHAEMOLYTICUS FROM CHRYSOMYA MEGACEPHALA (DIPTERA: CALLIPHORIDAE) IN TAK PROVINCE, THAILAND

Foodborne illness is a major public health problem caused by various pathogens, one such being Vibrio parahaemolyticus producing gastroenteritis. There is no previous report on whether the pathogen is transmitted by blow fly Chrysomya megacephala, the most predominant species of Thailand and a mechanical vector of various pathogens. Prevalence of Vibrio spp-carrying C. megacephala and genetic relationship among Vibrio isolates from blow flies, food and water samples were determined in three sites of Mae Sot District, Tak Province, Thailand (December 2016). Only V. parahaemolyticus was detected, with a prevalence of 7% in C. megacephala and in three seafood samples but none in water samples. All V. parahaemolyticus isolates (n = 10) were resistant to ampicillin and streptomycin, and one isolate from C. megacephala (14%) carried tdh, encoding a thermostable hemolysin. Enterobacteria repetitive intergenic consensus-PCR revealed four different amplicon size profiles, with one profile present in five strains from C. megacephala and three from seafood samples, all obtained at the same market. This is the first report of C. megacephala as a mechanical vector of V. parahaemolyticus in Tak Province, Thailand.