Bacteriological quality of drinking water in punjab: evaluation of H2s strip test

OBJECTIVE: To assess bacteriological quality of drinking water in Punjab and to evaluate usefulness of H2S strip test in comparison with multiple tube test. METHOD: Samples of water were tested using H2S strips and multiple tube test. Maximum bacterial contamination was observed in water from domestic pumps [95.83%]. Followed by tap water in rural areas of Punjab [91.30%] and tap water in Lahore [42.85%]. Bacterial contamination was significantly higher [p < 0.001] in rural areas as compared to urban areas. Comparison of results of testing water samples by H2S strip test and multiple tube test revealed that H2S strip is 87.24% sensitive and 100% specific for detection of bacterial contamination with a positive predictive value of 100%. It was also observed that 100% water samples negative for total coliforms were also negative by H2S strip method. Moreover, with increase in number of total coliforms in the water samples, positivity by H2S strip method also increased [samples with more than 10 total coliforms/100 ml were 100% positive by H2S strip method]. Therefore, H2S strip test can be used as alternative to multiple tube test for detection of bacterial contamination of water supplies. It is concluded that bacterial contamination of water is a significant problem in Punjab. It can be improved by regular monitoring of water supplies. For this purpose use of H2S strip test is advocated at house hold level

Chronic viral hepatitis: factors influencing response to alpha interferon

Viral hepatitis is a cause of considerable morbidity and mortality, both from acute infection and its chronic sequelae. Hepatitis B virus [HBV], hepatitis D virus [HDV] and hepatitis C virus [HCV] are the most important in terms of causing major morbidity and mortality throughout the world. According to the World Health Organization [WHO] estimates, 2.000 million people have been infected by HBV worldwide. About 5% of all HBsAg carriers are estimated to be infected with HDV. Although not as prevalent as HBV infection in terms of worldwide figures, HCV more often results in chronic hepatitis [40 - 60% of post transfusion hepatitis patients], progressing to cirrhosis in 20% of cases and sometimes to hepatocellular carcinoma. Recently, a new flavivirus hepatitis G virus [HGV] has been identified as an uncommon cause of post transfusion hepatitis, which has infected 1.5% of blood donors