Opisthorchiasis and intestinal fluke infections in northern Thailand.

Four hundred and thirty-one residents from 16 provinces in northern Thailand who had previously been found positive for Opisthorchis viverrini or Opisthorchis viverrini-like eggs were given praziquantel 40 mg/kg. The stool was collected for 4 to 6 times and examined for adult worms. The prevalence of Opisthorchis viverrini in this group was 11.6%. Intestinal flukes, Haplorchis taichui and Haplorchis yokogawai, were predominantly found in 63.11% and 10.44% respectively. Other intestinal flukes (Centrocestus caninus, Echinostoma malayanum, Haplorchis pumilio, Phaneropsolus bonnei, Plagiorchid flukes, Prosthodendrium molenkampi and Stellantchasmus falcatus) were also found in small numbers.

Human infection of Centrocestus caninus in Thailand.

Examination of fecal samples, collected after treatment with praziquantel, of the persons positive with opisthorchioid eggs residing in the northern provinces of Thailand, was carried out. Five adults Centrocestus were recovered in one sample from Doi Saket, Chiang Mai and one adult was found in another fecal sample from Wiang Pa Pao, Chiang Rai. The worms had 26-30 spines arranging in two rows around the oral sucker which agreed with the character of C. caninus. This is the first record of natural human infection with Centrocestus in Thailand.

Intradermal simulated rabies postexposure prophylaxis using purified chick embryo rabies vaccine.

The antibody responses of 65 volunteers receiving an i.d. regimen (0.1 ml given at two sites on days 0, 3, 7 and 0.1 ml given at one site on days 30 and 90) were compared with the control group of 35 volunteers receiving the standard i.m. regimen. By day 14, seroconversion was observed in all vaccinees in both groups. Geometric Mean Titers remained higher than 0.5 IU/ml throughout the study period. At the end of the observation period on day 365, antibodies persisted in all subjects. The multisite i.d. PCEC regimen has been proved as immunogenic as the standard i.m. regimen. Both regimens were well tolerated. Thus, it would be the effective and cheapest available rabies post-exposure treatment using tissue culture vaccine.

Intradermal simulated rabies postexposure prophylaxis using purified chick embryo rabies vaccine.

The antibody responses of 65 volunteers receiving an i.d. regimen (0.1 ml given at two different sites on days 0, 3, 7 and 0.1 ml given at one site on days 30 and 90) were compared with a control group of 35 volunteers receiving the standard i.m. regimen. By day 14, seroconversion was observed in all vaccinees in both groups. Geometric mean titers remained higher than 0.5 IU/ml throughout the study period. At the end of the observation period on day 365, antibodies persisted in all subjects. The multisite i.d. PCEC regimen has been proved as immunogenic as the standard i.m. regimen. Both regimens were well tolerated. Thus, it would be the effective and cheapest available rabies postexposure treatment using tissue culture vaccine.