Epidemiology of XXXX in Somalia: inference from a cross-sectional survey of serological markers.

@entity1 @entity281 @entity1956
@entity1956 markers were determined by radioimmunoassay in 383 adults from different areas of Somalia and in 135 pregnant females and 428 @entity1 from Mogadishu. The highest incidence of HBsAg among adults was among nomadic males (20/85; 23%). The frequencies were lower in males from the agricultural and coastal area, i.e. 16/93 (17%) and 14/98 (14%) respectively. The lowest frequency of HBsAg was among @entity1 from the coastal area (6/72; 8%). Among the pregnant @entity1 14 were positive for HBsAg, none of whom had HBeAg. Low levels of positivity for HBsAg were found both among @entity1 under 4 years and among those between 4 and 13 years of age - 3/94 (3%) and 5/128 (4%) respectively. In the age group 15-19 years, 50% showed seroconversion from HBeAg to anti-HBe. 7 out of 41 HBsAg carriers of ages over 20 had HBeAg. Early seroconversion from HBeAg to anti-HBe and a low level of HBsAg positivity in @entity1 indicate that vertical transmission is not important in Somalia. The low frequency of HBsAg in Mogadishu @entity1 may have one of the following explanations: (i) the @entity281 occurs during adolescence, (ii) Mogadishu is a low-prevalence area and the examined adults were not born in Mogadishu, or (iii) a change in @entity1956 has taken place in the area during the last 2 decades and the relatively higher prevalence of HBsAg in adults might reflect higher rates of @entity281 in their childhood.
