POPLINE Document Number: 194671
Author(s):
Mulders MN
Venard V
Njayou M
Edorh AP
Oyefolu AO
Source citation:
Journal of Infectious Diseases, 2004 Jul 15;190(2):400-408.
Abstract:
Sub-Saharan Africa suffers from an excessively high endemicity of hepatitis B virus (HBV), but little is known about the prevalent genotypes. In this study, we investigated the PreS1/PreS2/S genes of 127 viruses obtained from 12 locations in Mali, Burkina Faso, Togo, Benin, Nigeria, Cameroon, and the Democratic Republic of Congo. Except for those obtained from the Cameroon HIV cohort (18/22 HBV genotype A), 96 of 105 sequences belonged to HBV genotype E (HBV/E), and viral DNA was very similar (1.67% diversity) throughout this vast HBV/E crescent, which spans 6000 km across Africa. The low diversity suggests that HBV/E may have a short evolutionary history. Considering a typical mutation rate of DNA viruses, it would take only 200 years for the strain diversity of HBV/E viruses to develop from a single introductory event. The relatively recent introduction of HBV/E into humans would also explain its conspicuous absence in the Americas, despite the forced immigration of slaves from west Africa, until the early 19th century. Infection during infancy is mostly associated with chronic carrier status, and this combination can account for the explosive spread of virtually identical viruses within a community, but whether other routes of long-range transmissions must be considered becomes an important question. (author's)
Keywords:
Africa, WesternIndex page
Research Report
Adults
Hepatitis
HIV Infections
Disease Transmission Control
Laboratory Examinations and Diagnoses
Developing Countries
Africa, Sub Saharan
Africa
Age Factors
Population Characteristics
Demographic Factors
Population
Viral Diseases
Diseases
Prevention and Control
Examinations and Diagnoses