A Hepatitis A outbreak occurred in Mukim Hulu Langat, Hulu Langat district from April 2002 to October 2002. Of the 51 cases notified, most were among students and the ethnic groups involved were Malays and the Orang Asli (local indigenous community). Epidemiological investigations revealed that the cases were localized along rivers used for recreational activities in this area. River water analysis indicated human faecal contamination and it was believed that the contamination was due to the Orang Asli community living upstream. This occurred due to lack of toilet facilities, water at point of use and the existing traditional practices of the Orang Asli community. Control measures instituted were intense health education to the Orang Asli to avoid using the rivers for defecation, multi agency efforts to provide sanitary toilets and adequate water to the villages affected. Future measures include conducting a sero- prevalence survey to determine the feasibility of Hepatitis A immunization to the susceptible population in this area. The outbreak that began in April 2002 was controlled by October 2002.
Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm(2) resulted in transfer of 9.2% +/- 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% +/- 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.