Multi-infection with helminths in adults from northeast Thailand as determined by post-treatment fecal examination of adult worms.

Six hundred and eighty-one residents from 16 provinces in northeast Thailand who had previously been found positive for Opisthorchis viverrini and Taenia spp. eggs were given 40 mg Praziquantel (Bayer, Germany), per kg body weight. The total stool output for one to three days was collected and examined for adult worms. The prevalence of O. viverrini in this group was 92.4%. The intestinal flukes Echinostoma malayanum, E. ilocanum and E. revolutum were found to be high in males, with 8.3%, 8.1% and 0.8%, respectively. Minute intestinal flukes such as Haplorchis taichui, H. pumilio, H. yokogawai, Phaneropsolus bonnei, Plagiorchis harinasutai, Prosthodendrium molenkampi and Stellantchasmus falcatus were found to be 7.8%, 6.2%, 2.9%, 15.0%, 0.7%, 19.4% and 0.3%, respectively.