Sero-epidemiological study of hepatitis A virus infection among hill-tribe youth and household environmental sanitation, a hill-tribe community in northern Thailand.

A cross-sectional analytic study of 190 hill-tribe youth in a community in the north of Thailand was conducted to investigate the sero-prevalence of HAV and factors related to positive anti-HAV antibody. The studied youth, whose ages ranged from 15 to 24 years, were interviewed about socio-economic status and personal hygiene. Blood specimens were collected to detect anti-HAV by ELISA commercial kit. Household environmental sanitation conditions were observed and drinking water samples were screened for bacterial contamination using SI2 medium. Following the anti-HAV assay, the studied youth were divided into two groups: anti-HAV positive, and anti-HAV negative. The studied variables of the two groups were analyzed by chi2 test to find factors related to anti-HAV positivity. The results revealed that 87% of the studied youth were positive for anti-HAV. There was no statistically significant difference between age group/gender and anti-HAV positivity, p = 0.46 and 0.16, respectively. Approximately 35.79 to 45.79% washed their hands with soap before preparing food, before eating and after using the latrine. About 88% did not improve the potability of their drinking water. The results of screening for bacterial contamination in drinking water samples found that 73.53% were contaminated with coliform bacteria. Factors related to positive anti-HAV antibody included monthly income, number of household members, use of latrine, hand-washing with soap after using latrine, household refuse management and control of insects and rodents; p = 0.04, 0.007, 0.013, 0.008, <0.001 and <0.001, respectively. The findings suggested that appropriate household environmental management should be improved in this community to reduce HAV transmission.

Aluminium leaching from aluminium cooking utensils into foods.

Leaching of aluminium content from those aluminium utensils into foods could have an effect on health. Study on factors affecting the leaching amount of aluminium from the aluminium cooking utensils into food being cooked was undertaken. For types of foods were cooked using alminium cooking utensils under different conditions as follows: sour soup cooked at pH of 3.0 and 4.0; clear soup cooked with salinity of 4.0 and 8.0 ppt; fish fried for 4 and 6 minutes; and swamp cabbage (Chinese) stir fired at temperature of 200 oC and 300oC. Stainless-steel cooking utensils were used as control units. All the cooked foods were analyzed for aluminium content by means of atomic absorption spectrophotometry. Results revealed that pH level of foods as well as cooking temperature affected the amount of aluminium leaching from the aluminium cooking utensils into foods; that is aluminium content increased with lower pH or higher temperature. In contrast, neither level of salinity of foods nor cooking time affected the aluminium content leaching from the aluminium cooking utensils into foods. In general, the amount f aluminium leaching from aluminium utensils into foods being cooked was not found to be high in this study.