[Study on the characteristics of sexual networks for men who have sex with men recruited at different sites in Harbin].
OBJECTIVE
To identify the characteristics of the sexual networks and HIV/AIDS related high-risk behaviors among MSM in Harbin city, and to evaluate the possibility of HIV transmission among MSM and from MSM to general population.


METHODS
A face to face questionnaire investigation was conducted among 673 MSM aged above 18 years older from May to July, 2006 in Harbin, Heilongjiang province. The Key-informant sampling and time-location sampling methods were used at different sites to recruit objectives, including bars, bathrooms, parks and social networks.Mixing matrices were computed based on the demographic characteristics of MSM and their sexual partners. Sexual networks analysis by egocentric methods, such as network size, density and sexual mixing patterns.


RESULTS
A total of 647 questionnaires were completed. The number of them recruited from bars, bathrooms, parks and social networks were 229, 291, 36 and 91. The average size of sexual networks was 14 persons, the least network density was 0.14. The proportion of having sexual relationship in the past year was 30.5% (647/2123). Of which recruited at bars, bathrooms, parks and social networks, the proportions of having long-term relationship with their sex partners were 22.8% (159/699), 35.9% (329/917), 26.4% (28/106) and 32.7% (131/401), respectively. There was statistical significance in MSM having sexual relationship with their partners at different recruited places (chi(2) = 34.07, P < 0.01). Sexual networks of MSM from public bathroom was larger with an average number of 18. Only 35.9% (329/917) of them had long-term relationship with their sex partners. A tendency for age and marriage pairing to cluster around main diagonal suggesting that MSM were similar to choosing sexual partners in the respect of age and marriage status. The proportions of consistent condom use in the past 6 months were 40.9% (647/2123).


CONCLUSIONS
MSM from different sites have greatly different sexual networks characteristics. Sexual mixing patterns are weakly assertive in the MSM and potential of HIV spread among MSM exists.
National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Hou-lin
HL
Tang
Fan
F
Lü
Da-peng
DP
Zhang
Yu-hua
YH
Wu
Jie
J
Zhang
D000163:Acquired Immunodeficiency Syndrome / Q000209:etiology; D000293:Adolescent; D000328:Adult; D000368:Aged; D018451:Homosexuality, Male / Q000523:psychology* / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D044382:Population Groups; D011998:Recreation; D012309:Risk-Taking; D012725:Sexual Behavior; D012944:Social Support; D011795:Surveys and Questionnaires; D055815:Young Adult