HIV-1 Diversity in Tanzania and its Implication toward Development of Effective Vaccines: A Review Article

Abstract

Background: Human immunodeficiency viruses (HIV) are characterized by extremely high genetic variability. This extensive heterogeneity resulted from high error rate of reverse transcriptase enzyme in combination with fast turnover of virions among HIV-infected individuals. With geographical distribution of subtypes its evolution and unpredictable process and intermixing of HIV-1 variants is inevitable. Recombinant viruses contribute already substantially to the global pandemic especially in sub-Saharan African. East Africa studies has shown more complex mixture of HIV-1 Subtypes and associated recombinant virus especially in Tanzania. Objective: To review past and current literature on HIV-1 diversity and challenges emerging toward effective, safe and cheap HIV-1 Vaccine in Tanzania and gives out some recommendations that could help in tackling these challenges. Methods: A Pub med, HINARI, Springer online archives and Google Scholar literature of publication on HIV-1 Subtypes and Vaccine was performed to identify articles on ‘HIV-1 diversity’, ‘HIV-1 Subtypes’, ‘HIV-1 and vaccine’ , ‘HIV-1 Evolution’, ‘HIV-1 subtypes and vaccine’ and HIV-1 diversity and vaccine in Tanzania. Articles resulting from these searches in the articles were reviewed. Findings: The predominant HIV-1 subtypes across African continent are HIV-1 Subtype C with few cases of Subtypes A in east Africa and recombinant forms in West Africa. In Tanzania the predominant subtype was HIV-1 Subtype A in Northern side compared with HIV-1 subtype C in the western and central part of the country. We also reported few cases of HIV-1 Subtype D and B in the shore of lake Victoria near Uganda border. Conclusion: With regard to HIV infection, we are facing a unique challenge where by a concept of vaccine as a standalone prevention measure to end the epidemic is unlikely. Therefore it is a high time to join global effort to come up with a new paradigm of joining potentially promising ideas toward effective HIV/AIDS vaccine. In area like Tanzania where HIV-1 is very diverse can be taken as an opportunity to harness the possibility of finding broad neutralizing antibodies across all strains for a good candidate of HIV-1 vaccine.