This study evaluated the anti-giardial activity of chloroform, methanol and water extracts of 12 medicinal plants (39 extracts), commonly used as self medication by AIDS patients in southern Thailand. The plant extracts and a standard drug, metronidazole, were incubated with 2x10(5) trophozoites of Giardia intestinalis per millilitre of growth medium in 96-well tissue culture plates under anaerobic conditions for 24 h. The cultures were examined with an inverted microscope and the minimum inhibitory concentration and the IC50 value for each extract was determined. The chloroform extracts from Alpinia galanga, Boesenbergia pandurata, Eclipta prostrata, Piper betle, Piper chaba, Zingiber zerumbet, and the methanol extracts from B. pandurata and E. prostrata were classified as "active", i.e. with an IC50 of <100 microg/ml, whereas the chloroform extract from Murraya paniculata was classified as being "moderately active". This study shows that extracts from some medicinal plants have potential for use as therapeutic agents against G. intestinalis infections.

Cryptosporidium species are frequently associated with diarrhea among AIDS patients in Thailand, and dairy herds are a possible source of some of these infections. A cross-sectional study was performed to determine if Cryptosporidium is present among dairy cows in Thailand. Fecal samples were randomly collected from 363 Holstein-Friesian dairy cows from 108 of 860 farms in the Nong Pho region of central Thailand. The average prevalence of Cryptosporidium among dairy cows was 9.4%, according to an assay for Cryptosporidium-specific antigen (CSA) and 0.6% by microscopic examination of acid-fast stained feces. CSA was detected in all host age categories tested, but was most prevalent among calves (15.1%). Overall, 31.5% of farms were contaminated with Cryptosporidium infections. Fifty percent of poorly managed farms had CSA-positive cows, which were more likely to contaminate water and raw milk, while 12.9% of farms with acceptable management practices had CSA-positive cows. There was no association between the detection of Cryptosporidium and other gastrointestinal parasites. These results indicate that Cryptosporidium is enzootic among Thai dairy cattle, and suggest that cattle could have a role in zoonotic cryptosporidiosis in Thailand.

We report a case of sinusitis caused by mixed free-living amoebae, Acanthamoeba and Naegleria, in an immunocompetent host; this has not been documented before. Free-living amoebae should be considered in the differential diagnosis of pathogens that cause sinusitis with or without central nervous system involvement, especially when bacteria or fungi are not found by smear, biopsy or culture.