A study of HIV-1 genetic diversity in the Czech Republic: 1986-2007.

SUMMARY Background: The global HIV/AIDS epidemic consists of a number of regional epidemics caused by different HIV-1 subtypes prevailing in different regions. Objectives: To study changes in genetic diversity of HIV-1 strains isolated in the Czech Republic (CR) over a more than twenty-year period (1986–2007). Study Design: HIV-1 strains isolated in CR from 1986 to 2007 were subtyped by pol gene sequencing followed by phylogenetic analysis. The role of HIV-1 subtyping in molecular epidemiology was considered. Results: A wide range of HIV-1 subtypes were found, with subtype B, into which 76.6 % of 534 HIV-1 isolates were classified, being predo minant during the whole study period. An increasing number of non-B subtypes A1, C, D, F1, G and some recombinant forms (CRF 01_AE, CR F 02_AG and CRF 06_cpx) were identified after 1990. Conclusions: The absolute predominance of subtype B among HIV-1 strains in the Czech Republic ended in 1991 when different non-B subtypes had been introduced into the country. The East-West migration is responsible for the introduction of HIV-1 subtypes prevalent i n Eastern European and some Asian countries. Genetic analysis of HIV-1 isolates from a given region can be helpful in tracing the course of the HIV/AIDS epidemic.