Molecular Transmission Network And Early-warning Study On Recombinant Of HIV Strain In China

Objective1.Using HIV molecular transmission network to study the prevalence of high risk population of HIV-1 CRF01_AE,aim to reveal its network transmission pattern and predict the risk of population for guide of precise intervention and improvement of prevention effect.2.To identify the credibility of self-reported transmission behavior in HIV-infected patients by molecular transmission network and statistical model,and to improve the accuracy of epidemiological data.3.To find and identify new CRFs in China for early-warning of HIV epidemic.Methods1.3561 HIV-1 CRF01_AE sequences sampled in China between 1996 to2014 from the international HIV database and the project of transmitted drug resistance were collected to construct four cumulate molecular transmission networks?CTNs??2008,2010,2012,and 2014?.Parameter of Population Transmission Risk?TR?,Grading TR estimation and the power-law function were applied to elucidation the dynamics of risk groups.2.The linkage of MSM,heterosexual men and heterosexual women in CRF01_AE molecular transmission networks was analyzed.Then,the decision tree model was used to analyze the self-reported persons inconsistent with the linkage for estimation of the error proportion of self-reported sexual behavior.3.The recombination patterns of new circulating recombinant strains from current national HIV molecular epidemiology survey samples were analyzed by RIP,jpHMM and SimPlot.Result1.In 2008 network,heterosexual and MSM each accounted for 16%;CRF01_AE lineage 1 accounted for the highest proportion?45%?,followed by CRF01_AE lineage 4?27%?and lineage 5?14%?.In 2014 network,the proportion of heterosexual increased to 25%,while the proportion of MSM increased rapidly to 41%;CRF01_AE lineage 4 accounted for 45%and ranked first,while the proportion of lineage 1 dropped to the second?25%?.2.In the second level population,MSM accounted for at least 2/3 TR since the 2008 CTN.In the third level population,the proportion of TR of MSM increased from 37%to 70%.In the fourth level population,heterosexuals held the highest proportion of TR?55%?,followed by IDUs?26%?,MSM?10%?and BT+FPDs?8%?in the 2008 CTN.After that,the proportion of TR of MSM gradually rose and almost equaled heterosexuals?44%?in the 2014 CTN.3.The degree power-law curves fitted from MSM and heterosexuals in the2008,2010,and 2012 CTNs intersect.In detail,between the 2008 and 2012CTNs,the frequency of heterosexuals was more than MSM among individuals with a higher degree and less than MSM among individuals with a lower degree.The curves corresponding to 2014 present no intersection?when both degree and frequency were?1?.In other words,the frequency of MSM was not lower than heterosexuals regardless of the degree value.4.After model analysis,99%self-reported MSM were estimated to be homosexual;100%self-reported heterosexual women were estimated to be heterosexual transmission;76%self-reported heterosexual men were estimated to be heterosexual transmission,and other 24%were estimated to be homosexual transmission,of which 10%linked to MSM only and 14%linked to both MSM and heterosexual in the network.5.A new HIV-1 circulating recombinant form?CRF79₀107?with CRF01_AE backbone was identified.CRF79₀107 was composed of three CRF01_AE segments and three CRF07_BC segments.The map of recombinant genome is as follows:I_CRF01AE?790-4328 nt?,II_CRF07BC?4329-4808 nt?,III_CRF01AE?4809-6559 nt?,IV_CRF07BC?6560-8592 nt?,V_CRF01AE?8593-9095 nt?and VI_CRF07BC?9096-9411 nt?.Conclusion1.The high risk population of CRF01_AE in China was changed from heterosexual and IDU to heterosexual and MSM.The risk of MSM shows a trend beyond heterosexual.The use of molecular transmission network can guide the intervention in targeting high-risk populations of HIV transmission.2.In China,approximately 24%self-reported heterosexual men with HIV infection may conceal homosexual behavior,suggesting that molecular epidemiological evidence can improve the accuracy of field epidemiological data.3.For the first time,a new CRF between CRF01_AE and CRF07_BC--CRF79₀107 is found in China,which has been popular among sexual transmissionpopulationinShanxiProvince.TheHIVmolecular epidemiological warning study shows that MSM and heterosexual have a risk of mutual transmission in Shanxi.