经性途径传播的HIV感染者性行为特征及对二代传播率的影响

目的：了解经性途径传播的HIV感染者的性行为特征，并估计其二代传播率。方法：通过现场调查和文献查阅对新报告的经性途径感染的HIV阳性者感染告知前6个月内的相关情况进行调查，应用二代传播率数学模型估计二代传播率。结果：共调查HIV感染者769例，其中女性186人，异性性行为男性(men who have sex with women，MSW) 286人，男男性行为者(men who have sex with men，MSM)242人，双性性行为男性(men who have sex with men and women，MSMW)55人；其平均性伴数分别为2.29，1.61，3.32和4.10；6个月的性频次分别为26.03，20.97，14.77和25.51次；不安全性行为比例分别为74.14%，73.53%，59.60%和72.06%；6个月的二代传播率分别为0.0095，0.0151，0.1759和0.1985。在其他因素固定不变的条件下，如果性伴数减少1个、每月性频次减少1次、不安全性行为比例降低20%，则二代传播率将分别下降30.13%~82.00%，23.00%~49.51%和16.10%~19.09%。结论：在HIV感染者中，MSMW有最大的二代传播风险，性行为特征改变能显著降低HIV的二代传播风险。

Characteristics of HIV’s sexual behavior and their effect on the secondary transmission rate

Objective: To analyze the sexual behavior characteristics of the sexually transmitted HIV-positive people and to estimate the secondary transmission rate.Methods: Field investigation and literature review were conducted among sexually transmitted HIV-positive people to collect general information during the last 6 months before notification of HIV infection. A mathematical model was used to estimate the secondary transmission rate.Results: A total of 769 HIV-positive people were recruited for the study, 186 of them were women, 286 were men who have sex with women (MSW), 242 were men who have sex with men (MSM) and 55 were men who have sex with men and women (MSMW). During 6 months, the average sex partner among these 4 groups were 2.29, 1.61, 3.32 and 4.10, respectively; the sexual behavior frequency were 26.03, 20.97, 14.77 and 25.51, respectively; the rates of non-use of condom were 74.14%, 73.53%, 59.60% and 72.06%, respectively; the secondary transmission rate were 0.0095, 0.0151, 0.1759 and 0.1985, respectively. Under constant conditions of other factors, the secondary transmission rates decreased by 30.13%-82.00%, 23.00%-49.51%, and 16.10%-19.09%, respectively, if there was a reduction in 1 sex partner, 1 time/month for the sexual frequency and 20% of rate for non-use of condom.Conclusion: The HIV secondary transmission from MSMW HIV-positive people to general population was the highest. Change in sexual behavior of the HIV-positive people can decrease the HIV secondary transmission rate significantly.