Endemic Cryptosporidium and Giardia lamblia infections in a Thai orphanage.

We conducted a point prevalence survey for enteric protozoa in 205 institutionalized orphans 1-61 months of age in Bangkok, Thailand. Cryptosporidium was identified in 17 children (8%), Giardia lamblia in 42 (20%), and 3 children (1%) had both parasites. At the time of diagnosis, diarrheal symptoms were present in a minority of subjects: 36% of children with Cryptosporidium alone, 10% with G. lamblia alone, and in 20% of those with neither parasite. Although chronic nutritional status (height/age) was similar in all groups, acute nutritional status (weight/height) was lower only in children with Cryptosporidium (Z score = -1.39 +/- 0.13) compared with children with G. lamblia (mean Z score +/- SEM = -0.56 +/- 0.26) or neither parasite (Z score = -0.78 +/- 0.13; P = 0.05). Detectable levels of Cryptosporidium-specific IgG antibodies by ELISA were identified in 15 of 16 Thai children with Cryptosporidium and in 17 of 19 Thai children without Cryptosporidium (mean OD +/- SEM = 1.27 +/- 0.18 vs. 1.06 +/- 0.13, respectively), but in only 1 of 18 sera from toddlers in day-care centers in Denver, CO (OD = 0.128 +/- 0.03). Although neither infection with Cryptosporidium nor G. lamblia was consistently associated with acute diarrheal symptoms, Cryptosporidium was more often associated with depressed acute nutritional status than G. lamblia. The high prevalence of specific antibodies to Cryptosporidium in Thai orphans suggests an association between high rates of exposure with asymptomatic excretion of the parasites.

Human infection with Bertiella studeri in Thailand.

Bertiella studeri infection in a-26-year old Thai female was reported from Thailand. The intermittent diarrhoea and evacuation of a segment of the tapeworm brought the patient to the hospital. The parasitological description of the tapeworm specimen is reported.

Treatment of Opisthorchiasis viverrini in hamsters with albendazole.

Efficacy of many drugs against Opisthorchis viverrini in man were shown by the percentages of egg reduction and the absence of egg in faeces. In some cases, however, the eggs reappeared after a period of time. The pathological changes of the bile duct could cause partial or even complete obstruction of the bile passages, thus resulting in the occurrence of natural egg reduction. Albendazole, a broad spectrum anthelmintic was used to treat opisthorchiasis viverrini in hamsters. At dosage of 100 mg per kg body weight twice daily for three consecutive days, the drug yielded an average of 81.5% of worm reduction at four months after medication. In this study complete cure was not obtained.

Man, an accidental host of Cyclodontostomum purvisi (Adams, 1933), and the occurrence in rats in Thailand.

Two adults of Cyclodontostomum purvisi were recovered from faecal specimen of a 47 year-old male who had suffered from capillariasis, in Kaeng Khoi District, Saraburi Province, Thailand; Adults of C. purvisi were also recovered from the large intestine of B. savilei and B. indica trapped in the same area and in Pak Philli District, Nakhon Nayok Province. This is the first record of human infection with C. purvisi and of the occurrence in B. savilei and B. indica in Thailand.

Mekong schistosomiasis. 4. A parasitological survey of wild rodents, domestic pigs and cattle on Khong Island, Laos.

No evidence of infection with the Mekong Schistosoma was found in 12 Rattus exulans, 81 R. r. molliculus, and 10 Bandicota savilei caught in the vicinity of and downstream from the schistosomiasis transmission focus on Khong Island, South Laos, and examined by dissection and portal perfusion. Likewise, no eggs of the Mekong Schistosoma were detected in faeces of 15 domestic pigs or 43 domestic cattle examined on Khong Island both by merthiolate-iodine-formalin concentration and by the hatching technique. These results suggested that the wild rodents listed above, as well as pigs and cattle in the vicinity of Khong Town, may not contribute significantly to the transmission of the Mekong Schistosoma under present conditions.

Diagnosis of intestinal amebiasis using salivary IgA antibody detection.

Attempts were made to use soluble antigen extract of strain HK-9 of Entamoeba histolytica to detect salivary IgA antibodies in intestinal amebiasis patients by using ELISA. Total salivary samples of 109 individuals were divided into four groups. Group I comprised 32 patients whose stools were positive only for E. histolytica cysts and/or trophozoites. Group II comprised 12 individuals whose stools were positive for E. histolytica and other intestinal parasites. Group III comprised 36 individuals whose stools were negative for E. histolytica but contained other intestinal parasites such as E. coli, E. nana, Blastocystis hominis, Trichomonas hominis, Giardia lamblia, Opisthorchis viverrini, and hookworm. Group IV comprised 29 healthy individuals whose stools were free from any intestinal parasitic infections. Based on the mean optical density, OD + 2SD of the results from 29 parasitologically negative healthy individuals, the cut-off OD value for salivary IgA antibodies was 1.265. Therefore, the assays were positive in 14 out of 32 (43.75%) of group I and 2 out of 12 (16.6%) of group II. The assays were positive in 16 out of 36 (44.44%) for group III whereas 2 out of 29 (6.90%) for group IV were positive. The overall sensitivity and specificity of the assays were 36% and 72%, respectively. The false positive rate was 28% and the false negative rate was 64%. The predictive values of positive and negative results were 47% and 63%, respectively. The diagnostic accuracy of ELISA for the presence of salivary IgA antibodies was 58%.

Intestinal capillariasis from Maha Sarakham Province, northeast Thailand: report of a case.

Intestinal capillariasis cases in Thailand were reported from the areas where people customarily ate raw freshwater fish. The present case came from Maha-Sarakham Province, Northeast of Thailand with the chief complaint of diarrhoea for one month. Eggs, larvae and adult Capillaria philippinensis were found in the faeces. The authors observed that protein-losing enteropathy was an early manifestation on this disease.

Amebiasis at an evacuation site on the Thai-Cambodian border.

Symptomatic intestinal amebiasis was highly endemic among the Cambodians living at Green Hill, an evacuation site on the Thai-Cambodian border between June 1987 through May 1989. Monthly incidence rates of intestinal amebiasis were determined to be inversely proportional to cumulative monthly rainfall. The highest incidence of amebic dysentery was 63/1000 in children 12-23 months old. Behavioral risk factors were investigated by conducting a case-control study. A questionnaire was administered to 73 families, each having at least one member with confirmed intestinal amebiasis within the past 3 months, and to 95 randomly selected control families having no individual with diarrhea for at least 3 months. Individuals from families with greater than 4 members were at higher risk for acquiring intestinal amebiasis. No significant differences in behavioral risk factors were identified between case and control families. Eighty-six percent of 51 water samples drawn from wells where amebiasis patients obtained their drinking water had greater than 10 coliforms/100 ml. The main route of transmission of E. histolytica was not identified, but was most likely via the fecal-oral route.

Control trial of soil-transmitted helminthic infections with pyrantel pamoate.

Pyrantel pamoate at dosage of 10 mg per kilogramme body weight was given to each villager at 4-6 weeks intervals for three times. The infection rates of hookworms among those who received and did not received the drug decreased from 60.5% pre-treatment to 19.6% after the third treatment and then increased to 32.4% one year after the third treatment. Infection rates of A. lumbricoides and Strongyloides spp. among the villagers who received and did not received the drug decreased from 27.5% pre-treatment to 2.2% after the third treatment and then increased to 20.1% one year later for the former, while the latter decreased from 6.5% pre-treatment to 2.3% after the third treatment and 0.4% one year later. The infection rate of T. trichiura was found to increase as pyrantel pamoate had no effect on this nematode. The authors suggested that to obtain more satisfactory results the anthelmintic drug used must likewise be effective against T. trichiura particularly in areas where this nematode is a public health problem. It was also suggested that the duration of treatment should be prolonged.

Ocular thelaziasis in Thailand: a case report.

Ocular thelaziasis in an 1-year-old boy from Phetchabun province was reported. A total of eleven worms was removed from his right conjunctival cul-de-sac. Only three males and four females were available for parasitological examination, and identified as Thelazia callipaeda, based on the position of the vulva relative to the esophagointestinal junction in the females, the pattern and number of caudal papillae and the presence of unequal spicules in the males. Subsequent survey of dogs in the vicinity of patient's home revealed the same species as those from the patient. Possible mode of infection in this patient was discussed.