Molecular epidemiology of hepatitis B virus infection in Tanzania.

Autor: Forbi JC; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Dillon M; CDC Tanzania, Division of Global HIV/AIDS, Center for Global Health, Centers for Disease Control and Prevention, Dar es Salaam, Tanzania., Purdy MA; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Drammeh BS; HIV Prevention Branch, Division of Global HIV/AIDS, Center for Global Health, CDC, Dar es Salaam, Tanzania., Tejada-Strop A; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., McGovern D; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Xia GL; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Lin Y; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Ganova-Raeva LM; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Campo DS; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Thai H; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Vaughan G; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Haule D; Tanzania National Blood Transfusion Services, Ministry of Health and Social Welfare, Dar es Salaam, Tanzania., Kutaga RP; US Centers for Disease Control and Prevention, Dar es Salaam, Tanzania., Basavaraju SV; HIV Prevention Branch, Division of Global HIV/AIDS, Center for Global Health, CDC, Dar es Salaam, Tanzania., Kamili S; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA., Khudyakov YE; Division of Viral Hepatitis, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, Atlanta, Georgia, USA.
Jazyk: angličtina
Zdroj: The Journal of general virology [J Gen Virol] 2017 May; Vol. 98 (5), pp. 1048-1057.
DOI: 10.1099/jgv.0.000776
Abstrakt: Despite the significant public health problems associated with hepatitis B virus (HBV) in sub-Saharan Africa, many countries in this region do not have systematic HBV surveillance or genetic information on HBV circulating locally. Here, we report on the genetic characterization of 772 HBV strains from Tanzania. Phylogenetic analysis of the S-gene sequences showed prevalence of HBV genotype A (HBV/A, n =671, 86.9 %), followed by genotypes D (HBV/D, n =95, 12.3 %) and E (HBV/E, n =6, 0.8 %). All HBV/A sequences were further classified into subtype A1, while the HBV/D sequences were assigned to a new cluster. Among the Tanzanian sequences, 84 % of HBV/A1 and 94 % of HBV/D were unique. The Tanzanian and global HBV/A1 sequences were compared and were completely intermixed in the phylogenetic tree, with the Tanzanian sequences frequently generating long terminal branches, indicating a long history of HBV/A1 infections in the country. The time to the most recent common ancestor was estimated to be 188 years ago [95 % highest posterior density (HPD): 132 to 265 years] for HBV/A1 and 127 years ago (95 % HPD: 79 to 192 years) for HBV/D. The Bayesian skyline plot showed that the number of transmissions 'exploded' exponentially between 1960-1970 for HBV/A1 and 1970-1990 for HBV/D, with the effective population of HBV/A1 having expanded twice as much as that of HBV/D. The data suggest that Tanzania is at least a part of the geographic origin of the HBV/A1 subtype. A recent increase in the transmission rate and significant HBV genetic diversity should be taken into consideration when devising public health interventions to control HBV infections in Tanzania.
Databáze: MEDLINE