Gnathostoma infective stage larvae in swamp eels (Fluta alba) at a metropolitan market in Bangkok, Thailand.

A total of 1,788 livers from swamp eels (Fluta alba), purchased at a market in Bangkok, Thailand, from April to July 2002, were studied for the prevalence and intensity of Gnasthostoma third stage larvae (L3s). Of all livers, 466 were infected with Gnasthostoma L3s (infection rate = 26%). The larvae recovered averaged 0.43 +/- 0.51 larvae/liver. All larvae were identified as Gnasthostoma spinigerm by morphological criteria. The prevalence of G. spinigerum L3s in the eels was much higher in the rainy season (June and July, 74%) than during April and May (8%). Therefore, prevention programs for gnathostomiasis should be emphasized during the rainy season.