A specific enzyme immunoassay (EIA) for the diagnosis of hepatitis C virus (HCV) infection was developed by recombinant DNA technology. Abbott HCV EIA was used to detect antibody to HCV (anti-HCV) in non-transfused and multiply-transfused thalassemia patients. None of 11 non-transfused patients had anti-HCV but 3 of 52 (5.8%) multiply-transfused patients had anti-HCV. This study showed that the prevalence rate of HCV infection is low in thalassemia patients. However, it is still important to identify hepatitis C virus infected patients in high risk groups because hepatitis C is associated with chronic hepatitis, cirrhosis and hepatocellular carcinoma.
110 normal, healthy adults were tested for antibody to hepatitis A (anti-HA) type IgG and 86 (78.2%) were found to be positive. An age-specific prevalence wasfound to be lowest in the lower agegroup and highest in the higher age-group. Out of 24 IgG positive individuals, only one was found to have type IgM. No significant difference in the incidence ofanti-HA type IgG was found between 42 patients in the Urology Unit, General Hospital, Kuala Lumpur and normal individuals (P > 0.1). 15 patients diagnosed as viral hepatitis were investigated for HA V IgG and IgM antibodies. 13 (86.7%) were positive for type IgG. Of this, only five (33%) were positive for the type IgM, suggesting that HA V is the cause of acute viral hepatitis in 33% of cases admitted to hospital as viral hepatitis.
Sera from 494 non-icteric patients admitted with illnesses other than overt hepatitis into the various hospitals in rural and urban Malaysia were tested for IgG antibody to hepatitis A virus. The overall antibody prevalence rate was 67.0% with rates increasing steadily from childhood 10 years old and under (39.4%) to middle-age and above (96.0%). No significant differences were noted between males (68.4%) and females (65.3%). The highest rate was in the Indians (80.6%), the lowest in the Chinese (55.9%) with Malays occupying intermediate position (70.3%). The rate in the rural patients (74.7%) was higher than that in the urban patients (65.5%) especially in the 21 to 40 year age-group where the rural patients had a rate of 96.7% compared with that in urban patients (61.1%). A comparison of antibody prevalence rates in different countries was made.
Serum samples were obtained within 3 days of capture from 106 cynomolgus monkeys (Macaca fascicularis) in peninsular Malaysia. Fifty-two monkeys were trapped on the fringes of palm oil estates and 54 in dense primary jungle. Sera were tested for antibodies to hepatitis A virus (HAV) with a commercial radioimmunoassay. Twenty-four animals had detectable serum anti-HAV activity (6 of 52 from palm oil estate sites and 18 of 54 from primary jungle sites). Among monkeys at both sites, antibody prevalence was strongly correlated with animal weight: overall only four of 69 monkeys (6%) weighing less than 2.0 kg had serum anti-HAV antibodies, while 14 of 29 (48%) weighing 2.0 to 3.9 kg, and 6 of 8 (75%) weighing 4.0 kg or more, had serum anti-HAV antibodies. These data suggest that wild cynomolgus monkeys in Malaysian jungles become infected with HAV or an HAV-like virus at a rate comparable to that of humans in the same region, and raise the possibility of a sylvatic cycle for HAV.
Sera from one hundred and fifty nine Malaysian individuals were screened for the prevalence of delta markers. These included 15 HBsAg positive homosexuals, 16 acute hepatitis B cases, 9 chronic hepatitis B patients, 13 healthy HBsAg carriers and 106 intravenous (i.v.) drug abusers, of whom 27 were positive for HBsAg only and the rest were anti-HBc IgG positive but HBsAg negative. The prevalence of delta markers in the homosexuals was found to be 6.7%, in the HBsAg positive drug abusers 17.8%, in acute hepatitis B cases 12.5%. No evidence of delta infection was detected in healthy HBsAg carriers, chronic hepatitis B cases and HBsAg negative i.v. drug abusers. With reference to i.v. drug abusers, the prevalence of delta markers was higher in Malays (23%) than in Chinese (7%) although the latter had a higher HBsAg carrier rate. Although the HBsAg carrier rate in the homosexuals was high, their delta prevalence rate was low as compared to drug abusers. In Malaysia, as in other non-endemic regions, hepatitis delta virus transmission appeared to occur mainly via the parenteral and sexual routes. This is the first time in Malaysia that a reservoir of delta infection has been demonstrated in certain groups of the population at high risk for hepatitis B.
We studied the presence of Hepatitis C Virus (HCV) antibodies in a defined Malaysian population and examined the association, if any, between HCV and the Hepatitis B Virus (HBV), using sensitive recombinant DNA second generation Enzyme Immunoassay (EIA) test kits. This sero-prevalence study comprised 1,434 sera from eleven distinct groups comprising intravenous drug users (IVDU), haemophiliacs, male homosexuals, female prostitutes, healthy blood donors, staff of dialysis unit and laboratory personnel, chronic renal failure patients undergoing dialysis (CRFD), patients with liver cirrhosis, chronic active hepatitis, chronic persistent hepatitis and primary liver cancer. Except in laboratory personnel and dialysis staff, HCV antibodies were detected in each group of patients ranging from 3% in blood donors to 85% in IVDU. The main modes of HCV transmission identified were parenteral drug use, transfusion and/or dialysis related. The HBV was found to be the major viral etiological agent in 75% of chronic liver disease (CLD); while in 10% of cases both HCV and HBV were detected. HCV was implicated as the sole viral agent in only a small proportion (1.5%) of patients with chronic liver disease.