Epidemic dynamics of HIV/AIDS in Anhui province: a traceback study

  Objective  To traceback the epidemic dynamics of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) in Anhui province.

  Methods  Using Bayesian phylogenetic method, we displayed the epidemic dynamics of HIV/AIDS in Anhui province with time-dependent changes in effective reproductive number (Re) estimated based on genomic sequences of the two main subtypes (CRF 01AE and CRF 07BC) of HIV in the province.

  Results  The HIV subtype CRF 01AE was estimated to have been originated in 1982 (95% highest posterior density HPD: 1973 – 1990); while the subtype CRF 07BC was estimated to have been originated in 1992 (95% HPD: 1976 – 1998). A more obvious time-dependent change in Re from 2011 to 2014 was observed when combining the Bayesian phylogeny of the two main HIV subtypes and the Re median varied from the lowest of 1.34 (95% HPD: 0.94 – 1.80 ) to the highest of 2.20 (95% HPD: 1.67 – 2.84) during the period.

  Conclusion   Gene sequence analysis on prevalent HIV strains can reveal the trajectory of HIV/AIDS epidemic transmission in Anhui province.