Hepatitis B viral infection in South west Saudi Arabia.

n a recent issue of Saudi Medical Journal Ayoola et al1 reported a decline in the prevalence rates for hepatitis B virus (HBV) surface antigen (HBsAg) among Saudis domiciled in the Gizan Region of Saudi Arabia. Certainly, health care authorities would ensure an uninterrupted immunization with HBV vaccines in early infancy and ensure further reduction in the quantum of blood donors being positive for at least one HBV marker. A comprehensive analysis of apparently healthy Saudi volunteers with 3 serological markers revealed 33 Saudis exclusively positive for antibodies to HBV core antigen (anti-HBc). Aliquots from such patients, if available, should be tested for any low-level carriage of HBV. They might have been infected with the virus a long time ago, but with no development of antibodies to HBsAg, or antibodies level might subsequently have fallen to undetectable levels. They might have experienced recent clearance of HBsAg from the blood after a bout of acute hepatitis, or they might have a chronic HBsAg carrier stage. Alternatively, they might have had a low level carrier state with undetectable levels of HBsAg.2 To distinguish these possibilities, it might have been preferable to test them for circulating DNA of HBV. Furthermore, low level carriers could be tested for active viral replication by measuring levels of HBV e antigen (HBeAg) and HBV DNA. These tests might assist in selecting those eligible for therapeutic antiviral intervention with interferon and lamivudine. During the late 1990's among those aged less than 10 years, the HBsAg prevalence rate was 0.9%.1 This accumulated figure, from 10 hospitals in the Gizan region appears to be in sharp contrast to the HBsAg prevalence recorded during the 1980s among children less than 12-years-old at one of the hospitals in the region. Among Saudi children seeking treatment for minor ailments at the Gizan General Hospital, the prevalence rate for HBsAg was 11.1%.3 An in depth analysis of the HBsAg prevalence rate among the current Saudi infants and children reporting for minor ailments at the Gizan General Hospital would be desirable. Such an exercise would more than substantiate the reported efficacy of the existing immunization services in the region.1 Ayoola et al1 have quoted the 1980's overall HBV exposure rate of 46.5% and HBsAg prevalence of 12.7% among 724 Saudi adults residing in the Gizan Region. The sera from 724 Saudis screened were drawn from cord blood with 72 cases, infants aged less than one year with 41 cases, aged 1-11 years with 173 cases, aged 12-19 years with 112 cases, aged 20-39 years with 251 cases and those aged more than 40 years with 75 cases.4 In all probability the 1990s data from Group A comprising of 14883 blood donors has been drawn mainly from males aged 20-40 years. I Correspondence