Study On AIDS Dynamics Of Three High-risk Populations In Urumqi,Xinjiang

Objective:By constructing the HIV dynamic model of three high-risk groups（MSM,DUS,FSW）in Urumqi,Xinjiang,the HIV epidemic trend of high-risk groups in Urumqi was preliminarily analyzed and predicted,and the severity of HIV epidemic in Urumqi was quantitatively verified according to the basic regeneration number of each high-risk group.At the same time,the impact of the main interventions that determine the epidemic at different levels of intervention on the AIDS epidemic will be evaluated to provide reference opinions and basis for future disease prevention and control measures.Methods:（1）The sentinel surveillance data of HIV in three high-risk groups in Urumqi from 2009 to 2017 collected by Urumqi Center for Disease Control and Prevention in Xinjiang were processed for data,and the sentinel surveillance data were converted from the number of cases to the incidence rate,which was used to construct the dynamic model of the three high-risk groups in the later period.（2）First,according to the mechanism of AIDS transmission in different types of high-risk groups,corresponding AIDS dynamics models were constructed.Secondly,Matlab R2018a software and R 3.5.1software were used to simulate the dynamic models of high-risk populations,and the basic regeneration number R₀,which determines the transmission of AIDS in each high-risk population,was analyzed.At the same time,according to the HIV surveillance data processed in（1）,statistical methods were used in combination with R language statistical analysis software and MATLAB mathematical statistics software to perform parameter estimation,parameter sensitivity analysis,and model accuracy estimation.Finally,numerical simulations were performed on each dynamic model using the collected and estimated parameters to find the main intervention measures and use the dynamic model to make medium and long-term predictions.According to the analysis results of the dynamic model,determine one or more key factors of HIV infection in each high-risk population,and seek the best control strategy.Results:（1）The established HIV transmission dynamics model of MSM population has a reasonable fitting effect[mean absolute percentage error（MAPE）=10.89%,root mean square percentage error（RMSPE）=25.74%],and the basic regeneration number R₀≈0.2616（95%CI:0.2394⁰.9299）.This model predicts that the HIV positive rate of MSM population in Urumqi will decrease to 2%by 2027.The parameter sensitivity analysis found that the proportion of people developing from low-risk susceptibility to high-risk susceptibility,the proportion of HIV-infected persons developing AIDS,and the proportion of high-risk susceptibility people developing to low-risk susceptibility were the main factors affecting HIV prevalence in MSM populations.（2）The established dynamic model of HIV transmission in DUS population has a reasonable fitting effect[mean absolute percentage error（MAPE）=5.85%,root mean square percentage error（RMSPE）=8.85%],and the basic regeneration number R₀≈0.8417（95%CI:0.7328⁰.9720）.This model predicts that the HIV positive rate of DUS population in Urumqi will decrease to 7%by 2027.The parameter sensitivity analysis found that the infection rate of susceptible individuals,the success rate of detoxification among HIV-infected persons,the mortality rate of HIV-infected persons,and the proportion of HIV-infected persons developing AIDS were the main factors affecting HIV prevalence in DUS populations.（3）The established dynamic model of HIV transmission in FSW population has a reasonable fitting effect[mean absolute percentage error（MAPE）=24.43%,root mean square percentage error（RMSPE）=29.88%],and the basic regeneration number R₀≈2.5832（95%CI:1.8354³.1851）.This model predicts that the HIV positive rate of FSW population in Urumqi will rise to more than 2%by 2027.The parameter sensitivity analysis found that the proportion of FSW population and their male clients using condoms,the natural mortality rate of the male population,the natural mortality rate of the female population,the effectiveness of condoms,the number of sexual intercourses per individual male client population per unit time,the proportion of HIV-infected persons developing AIDS,and the number of sexual intercourses per individual FSW population per unit time were the main factors affecting HIV prevalence in FSW populations.Conclusion:HIV infection in MSM and DUS populations in Urumqi continues to be epidemic,and HIV infection in FSW populations is slowly rising at a low level.In order to effectively control the AIDS epidemic,in addition to adopting conventional control measures（such as condom promotion,strengthening publicity and education,etc.）,different prevention and control measures should be used for different high-risk groups.For the MSM population,it should be advocated to reduce the number of sexual partners,stop high-risk sexual behavior,and correct the separation of knowledge and behavior.Regarding the DUS population,the relevant departments,while combating drug trafficking and drug abuse,further increase the coverage of interventions for drug users,implement compulsory detoxification for drug users,increase the number of methadone maintenance treatment,increase the success rate of drug detoxification for HIV-infected people,and carry out clean needle exchange Use activities and other measures.For the FSW population and its male client population,relevant departments should recommend reducing or stopping high-risk sexual behaviors,and promote condom negotiation strategies among FSW populations.