[Incidence and risk factors of HIV infection among sero-negative spouses of HIV patients in Dehong prefecture of Yunnan province].

OBJECTIVE: To study the HIV incidence and risk factors among sero-negative spouses of HIV patients in Dehong prefecture of Yunnan province. METHODS: A cohort of sero-negative spouses of the HIV patients had been developed and followed up since November, 2005. HIV new infections and related behaviors had been investigated every six months. RESULTS: By the end of June, 2008, 790 sero-negative spouses of HIV patients had been recruited, of whom 702 were followed-up for at least one time. During the total 1202.35 person-years, 31 new HIV infections were identified, with an overall incidence of 2.58/100 person-years. The HIV incidence rates were 2.22/100 person-years in 2006, 2.95/100 person-years in 2007 and 2.74/100 person-years in 2008. Data from the Cox proportional hazard regression model indicated that those who resided in Yingjiang county [hazard ratio (HR) = 4.37, 95%CI: 1.48 - 12.90, P = 0.008], ever using drugs (HR = 3.49, 95%CI: 1.09 - 11.18, P = 0.035), or having an HIV-infected spouse who never exposed to antiretroviral treatment (HR = 3.60, 95%CI: 1.41 - 9.16, P = 0.007) were at higher risk for HIV infection. CONCLUSION: Sero-negative spouses of HIV patients in Dehong prefecture of Yunnan province had a relatively high incidence of HIV new infection during 2006-2008. More efforts should put on those people living in these areas, having a history of drug use or having an HIV-infected spouse who had never been exposed to antiretroviral treatment.

[Tracing the sources of newly reported HIV infections in Dehong prefecture of Yunnan province].

OBJECTIVE: To trace and provide HIV-testing among those having contacts with HIV-infected individuals at various levels in Dehong prefecture, Yunnan province and to evaluate the effectiveness and feasibility of such investigation as a supplemental strategy for HIV testing and control. METHODS: Newly reported HIV infections from August throughout October in Dehong prefecture, in 2008 were asked to provide contact information of persons whom they had high risk contacts with. Persons having had risk contacts with HIV-infected cases were here of interviewed and their blood tested on the sero-status of HIV. RESULTS: A total of 335 HIV cases were newly reported during this three-month period. A total of 309 cases of them and 148 HIV infections identified thereafter from their risk contacts were under informed consent, to participate in this study. A total number of 3395 risk contacts were reported, of whom only 20.7% (704/3395) had 'contact information' and 51.3% (361/704) were successfully located and interviewed, including 117 previously confirmed HIV infections and 244 people with unknown HIV status. The majority of them (203 or 83.2% of 244) were then tested for HIV and 56 (27.6% of 203) were tested positive for HIV. The proportion of having detailed contact information and the proportion of being traced or followed among reported risk contacts of HIV infections were 68.8% and 68.2% for spouses of HIV patients, respectively, which were much higher than those among commercial sex partners (1.2% and 16.7%), casual sex partners (37.3% and 22.3%) and peers who sharing needles (34.1% and 56.4%). CONCLUSION: Newly reported HIV infections reported a large number of risk contacts and new HIV infections were identified among them. It was extremely difficult to trace commercial sex partners or casual sex partners on their HIV infection status. Nevertheless, tracing the risk contacts of newly reported HIV infections seemed to be helpful in identifying new HIV infections and in understanding the nature of transmission towards controlling the HIV epidemics.

[Study on herpes simplex virus 2 infection and risky sexual behavior among HIV-infected patients in a county of Yunnan province].

OBJECTIVE: To explore the sero-prevalence and risk factors for herpes simplex virus 2 (HSV-2) infection and unprotected sexual behavior in an ethnically diverse population of HIV-infected subjects in a county of Yunnan province. METHODS: HIV-infected individuals attending for routine follow-up by local Center for Disease Control and Prevention (CDC) were recruited to participate in the study under 'informed consent'. A face-to-face questionnaire interview was administered to each participant. Blood was drawn for HSV-2 testing by HerpeSelect HSV-2 ELISA (Focus Diagnostics) and CD(4)(+) T counting. RESULTS: A total of 300 HIV-infected individuals participated in the study. The mean age of the subjects was 37.6 years with 76.7% as males. Ethnically, Han, Dai and Jingpo accounted for 44.3%, 37.3% and 16.0% of the sample, respectively. Half of the subjects reported HIV acquisition through injection drug use. The sero-prevalence of HSV-2 was 35.0%. Results from multiple logistic regression analysis indicated that individuals who acquired HIV through heterosexual contact were more likely to be HSV-2 positive than those who acquired HIV through injection drug use (OR = 4.244, 95%CI: 1.924 - 9.364), whereas Dai (OR = 0.300, 95%CI: 0.152 - 0.593) and Jingpo (OR = 0.376, 95%CI: 0.167 - 0.850) were less likely to be HSV-2 positive than the Hans. Among 105 people who were co-infected with HIV/HSV-2, 60 had sexual intercourses in the past 3 months and 41.7% of them reported no or inconsistent use of condoms. Most unprotected sexual contacts occurred within married couples. CONCLUSION: HSV-2 infection was highly prevalent among HIV-infected individuals in this county, and a significant proportion of HIV/HSV-2 co-infected subjects engaged in unprotected sex. HSV-2 testing, behavioral and biomedical interventions among HIV-infected individuals and their sexual partners should be involved in the local HIV prevention and control programs.

[Epidemiologic study on STD/HIV infections among tin mining workers in Gejiu, Yunnan province].

OBJECTIVE: To estimate human immunodeficiency virus (HIV)/sexually transmitted diseases (STDs) related knowledge, the prevalence and risk factors for HIV/STDs among tin miners in Gejiu, Yunnan Province. METHODS: A cross-sectional study was conducted in tin miners working at 5 mining regions from March to June 2006 in Gejiu City, Yunnan Province. A total of 1796 miners were enrolled in the study, and a standardized questionnaire was administered probing socio-demographic factors, knowledge of HIV/STDs and sexual behavior. 7 ml-volume venous blood and 15 ml urine specimens were collected for HIV/STDs testing. RESULTS: Twelve participants [0.7%] (12/1760) were identified HIV positive. While, the positive proportions for syphilis, herpes simplex virus type-2 (HSV-2), Neisseria gonorrhea and Chlamydia trachoma were 1.8% (31/1760), 9.6% (169/1760), 0.8% (14/1773), 4.8% (85/1773), respectively. The total prevalence of STDs was 14.9% (264/1776). Factors associated with HIV infection were illegal drug use (adjusted OR = 17.8; 95% CI: 4.0 - 78.8), frequencies of visiting female sex workers in the past twelve months (adjusted OR = 8.7; 95% CI: 1.9 - 39.0), tattoos (adjusted OR = 6.6; 95% CI: 1.8 - 24.0), surgical operation experiences (adjusted OR = 6.0; 95% CI: 1.6 - 22.5) and toothbrush sharing (adjusted OR = 5.6; 95% CI: 1.0 - 31.3). Factors associated with STDs infection were race (adjusted OR = 2.0; 95% CI: 1.5 - 2.7), age (adjusted OR = 1.7; 95% CI: 1.0 - 2.9), illegal drug use (adjusted OR = 2.3; 95% CI: 1.0 - 5.2), living with spouses (adjusted OR = 1.4; 95% CI: 1.1 - 1.9) and visiting female sex workers (adjusted OR = 1.9; 95% CI: 1.4 - 2.6). Only 4.1% (49/1201) of respondents aware the correct transmission routes of HIV. 21.6% (339/1569) of the miners who had previous sexual experience self-reported visiting female sex workers. CONCLUSION: HIV and other STDs are highly prevalent amongst miners in this region. In addition, the awareness of HIV/STDs is low and multiple routes of HIV transmission, such as heterosexual intercourse and IDU, were also observed in these study subject. HIV/STDs interventions should therefore be reinforced among the miners in this region.