Research On Dynamics Of HIV Drug Resistance Transmission Based On Bayesian Evolutionary Analysis

Background AIDS is one of the greatest threats to global public health.With the con-tinuous advancement of drug treatment,the problem of drug resistance gradually appears.Therefore,the study of the transmission trend of HIV/AIDS drug-resistant strains can pro-vide important reference value for the formulation and evaluation of prevention and control measures.Methods For the gene sequence of the four main subtypes(CRF01AE,CRF07BC,CR-F08BC and CRFBC,912 in total)of HIV/AIDS transmission in heterosexual populations in China,we applied Bayesian phylogenetic methods to infer the most recent common ancestor and its effective reproduction number(R_e)to trace the history of heterosexual HIV transmis-sion in China.At the same time,based on the transmission characteristics of HIV/AIDS among heterosexuals,we established a dynamic model to predict the transmission trend of HIV resis-tant strains in the future.Through using Markov Monte Carlo(MCMC)to fit the two effective reproduction numbers(R_e)from the two different methods above,we got some the uncertain parameters in the dynamic model.Considering the implementation of different measures to prevent and control the spread of HIV drug resistance,the dynamic model was numerical-ly simulated to predict and compare the effects of different measures on the transmission of drug-resistant strains.Results Based on the Bayesian phylogenetic analysis of 912 HIV-Pol gene sequences,we inferred that the most recent common ancestor of four sequences(CRF01AE,CRF07BC,CR-F08BC and CRFBC)were 1994(95%HPD:1991-1997)?1990(95%HPD:1986-1993)?1993(95%HPD:1991-1996)?1989(95%HPD:1979-1997),respectively.The weighted average effective reproductive number R_e~gdropped from 1.95 in 1994 to 1.73 in 2018.The effective reproductive number R_e~gof HIV/AIDS transmission among heterosexuals in China decreased from 1.95 in1994 to 1.73 in 2018,showing a trend of first increasing,then decreasing and finally becoming stable.Numerical simulation and prediction of the dynamic model found that merely increasing the treatment rate had very little effect on reducing infection and resulted in serious resistance problems.However,the”ideal-treatment effect”can significantly reduce the infection and can effectively improve the drug resistance problems caused by only increasing the treatment rate.In addition,we also studied the effects of different prevention and control measures on the dynamics of multiple drug resistance,and found that dual and triple drug resistance increased under both baseline and control measures,and that only increasing treatment rate would accel-erate the rate of increase.If the”ideal-treatment effect”is considered,the overall prevalence of HIV/AIDS will still show an upward trend,but it will slow down the increasing rate of multiple drug resistance and effectively reduce the occurrence of single drug resistance.