[A clustered epidemic investigation of non-marital non-commercial heterosexual contact of HIV in Zhejiang Province].

Objective: To identify the transmission relationship between HIV infection cases the non-marital non-commercial heterosexual contact in Zhejiang Province. Methods: When HIV positive was informed during January 2020 to January 2022, the staff conducted an epidemiological investigation to collect cases information on sociodemographic characteristics, mobility information, past HIV testing history, high-risk sexual behaviors, sexual partners, and etcetera. At the same time, 6-8 ml of blood from the new diagnosis of people infected with HIV before antiviral treatment was collected to separate the bleeding plasma. pol gene was amplified by nucleic acid extraction and PCR, sequenced by Sequencer 5.0 software, and Cytoscape 3.6.0 software was used to draw HIV molecular transmission network. Results: From January 2020 to January 2022, 88 HIV infected individuals were found in Pujiang County, of which 74 were transmitted through heterosexual transmission, of which 31 were infected through non-marital non-commercial heterosexual contact. Preliminary case studies have found that three female cases have engaged in unprotected non-marital non-commercial heterosexual contact with one male case. Among the 4 infected individuals, 2 of their spouses tested positive for HIV antibodies. Molecular transmission network monitoring was carried out on 65 newly diagnosed cases of heterosexual transmission with acquired sequences, forming 9 transmission clusters. The largest cluster contained 10 cases. A total of 11 HIV-infected individuals were involved in this HIV cluster epidemic. They were 3 males and 8 females, all over 50 years old and were farmers or rural housewives. They were traced to 7 sexual partners (6 negatives of HIV, 1 undetected). Among the 18 respondents' sexual social network relationships, there were 6 couples, 8 permanent partners, and 3 temporary partners. Among 11 HIV infected individuals, there were 9 cases of non-marital non-commercial heterosexual transmission and 2 cases of intramarital transmission. The epidemiological association between 7 non-married non-commercial heterosexual partners and case 2 (56-year-old male farmer), 3 cases confirmed by epidemiological investigation and molecular transmission cluster results, 3 cases confirmed by molecular transmission cluster and epidemiological investigation results, and 1 case confirmed by epidemiological investigation results. Conclusions: The transmission mode of this cluster epidemic was to spread HIV through heterosexual sex with a male case as the core, then cause the transmission within marriage and between fixed sexual partners. The combination of epidemiological investigation and molecular transmission network traceability survey supports the conclusion of this study.

[Prevalence of syphilis in HIV-infected patients with transmission risk and influencing factors in Zhejiang Province].

Objective: To investigate the prevalence of syphilis in HIV-infected patients with transmission risk and influencing factors in Zhejiang Province. Method: The information about the HIV-infected patients, who were alive, had been diagnosed with HIV for >1 year, had received no antiviral treatment or had HIV viral load ≥50 copies/ml, and were aged ≥15 years, reported in Zhejiang as of December 31, 2018 were collected from China Information System for Disease Control and Prevention. The information included general demographic characteristics, sexual behavior characteristics and antiretroviral therapy and syphilis serological test results. The prevalence of syphilis and the influencing factors were analyzed by logistic regression model. The SPSS 19.0 software was used for statistical analysis. Results: A total of 2 275 HIV-infected patients were at risk of HIV transmission, and 75.5% (1 717/2 275) of them were tested for syphilis, the prevalence rate of syphilis was 8.7% (150/1 717). Among the HIV-infected patients with syphilis, 11.3% (17/150) received no antiviral treatment, 38.7% (58/150) had viral load of 50-999 copies/ml and 50.0% (75/150) had ≥1 000 copies/ml. Multivariate logistic regression analysis showed that being men (aOR=2.04, 95%CI:1.06-3.96), homosexual transmission (aOR=1.53, 95%CI:1.04-2.27), history of sexually transmitted diseases (STDs) before HIV diagnosis (aOR=1.98, 95%CI:1.35-2.92) and HIV viral load ≥1 000 copies/ml (aOR=1.90, 95%CI:1.09-3.30) were the risk factors for syphilis. Marriage (aOR=0.47, 95%CI: 0.29-0.76) was a protective factor for syphilis. Conclusions: The prevalence of syphilis was high in HIV-infected patients with transmission risk in Zhejiang. It is urgent to carry out classified management and targeted intervention in HIV-infected patients, explore multi-disease prevention and treatment mechanism, strengthen syphilis screening and treatment in HIV-infected patients to reduce the transmission of HIV and syphilis.

[Status of personal information sharing on HIV between sexual partners among men who have sex with men who met casual sexual partners on the internet in Zhejiang province].

Objective: To identify the status and determinants of sharing personal HIV information with sexual partners among men who have sex with men (MSM) meeting their casual sexual partners on the internet. Methods: A cross-sectional study was conducted in five cities (Hangzhou, Ningbo, Wenzhou, Taizhou and Shaoxing) in Zhejiang province. The recruitment was enrolled by MSM social organization and in voluntary counseling and testing clinics, with a sample size of 793. A self-designed network questionnaire collected essential characteristics, HIV knowledge, sexual behavior, and sharing personal HIV status. SPSS 20.0 software was used for statistical analysis. Results: Among 767 MSM enrolled 302 MSM who reported finding casual sexual partners on the internet were enrolled in the analysis. MSM reported finding casual partners on the internet only, finding sexual partners online and in places were 62.6% (189/302) and 37.4% (113/302), respectively. Among those reporting web-based sexual behavior in the last six months, 54.6% (165/302) informed their partners of their HIV status, 49.2% (146/297) inquired about HIV status, and 42.9% (82/191) knew HIV status before sex intercourse, 75.8% (113/149) reported consistent condom use with HIV negative partners. The multivariable logistic regression analysis showed that related factors of inconsistent inquired HIV status of partners included 25-34 years old (aOR=2.17, 95%CI: 1.20-3.91), >2 partners on the internet in the last six months (aOR=2.13, 95%CI: 1.27-3.57), low-risk perception of HIV infection with online partners (aOR=1.96, 95%CI:1.14-3.35), numbers of HIV testing >1 times (aOR=0.38, 95%CI: 0.22-0.66). Conclusions: The willingness to know the HIV status of partners among MSM who met sexual partners on the internet was high but with a low rate of knowing their sex partner's HIV status in Zhejiang province. However, the successful implementation proportion was low. Therefore, it is necessary to pay attention to people who are elderly, with less conscience about the risk of the sex partners on the internet, have more sex partners, and have received few HIV tests. In addition, peer education was needed to promote related intervention programs.

[Mechanical analysis of the impact of the morphology of the iris and ciliary body on the central vault after posterior chamber phakic intraocular lens implantation].

Objective: To investigate the impact of the iris and ciliary body morphology on the central vault after phakic posterior chamber intraocular lens (pIOL) implantation. Methods: This research was based on the retrospective analysis of 123 patients (123 eyes) who underwent pIOL implantation in the Department of Ophthalmology, Affiliated Hospital of Qingdao University between June 2018 and June 2020. The anterior segment structure was observed with an ultrasound biomicroscope before surgery, and all morphological parameters of the iris and ciliary body were measured manually using the ImageJ software, including iris span (IS), iris convexity (IC), iris-ciliary body contact distance (ICCD) and iris-lens contact distance (ILCD). The ICCD was divided into Q1, Q2 and Q3 groups according to the equidistant distance of 0.36 mm. The lens thickness was measured with the IOLMaster. The horizontal corneal diameter and anterior chamber depth were measured using the Pentacam. The central vaults were measured by optical coherence tomography at 1 week, 3 months and 1 year after surgery. The relationships between vault values and preoperative parameters of the anterior segment were evaluated using the Pearson correlation analysis, Spearman correlation analysis, and multiple linear regression. The repeated measures ANOVA was applied to identify changes of vault values over time. Results: The mean values of the vaults at 1 week, 3 months and 1 year after surgery were (723±265) µm, (642±255) µm and (613±280) µm, respectively. The difference among them was statistically significant (F=50.143, P<0.001). The vaults continued to decline within 1 year after pIOL implantation, and the total decline was (122±86) µm. The vaults declined by (69±98) µm from postoperative 1 week to 3 months and by (52±54) µm from postoperative 3 months to 1 year. The regression formula showed that the pIOL size and ILCD were positively related with the vault, while the LT, IS and IC were negatively related with the vault at 1 week postoperatively (adjusted R²=0.404, P<0.001). The pIOL size and ILCD were positively related with the vault, while the IS and IC were negatively related with the vault at 3 months postoperatively (adjusted R²=0.342, P<0.001). The pIOL size was positively related with the vault, while the IS and IC were negatively related with the vault at 1 year postoperatively (adjusted R²=0.661, P<0.001). The vault values were higher in group Q3 compared to group Q1 at every timepoint, and the vault value was higher in group Q2 compared to Q1 at 1 year postoperatively. Conclusions: In the early postoperative period, eyes with a larger pIOL, shorter iris span, longer contact distance between the iris and ciliary body, and longer contact distance between the iris and lens were associated with a higher rate of excessive vaults. Meanwhile, eyes with a thicker lens and larger iris reverse convexity were more likely to obtain insufficient vaults. Within one year after surgery, the pIOL size, IS, IC and ICCD continued to impact on the vault. The ICCD, ILCD and IC can reflect the posterior chamber volume and change the haptic location and force, thus affecting the vault.

[Conducting analysis on HIV tracing and molecular network for promoting precise detection,prevention and control of AIDS].

The current sexual transmission of newly infected HIV cases is complicated in China. It is crucial for interrupting HIV transmission by HIV tracing and molecular network analysis,conducting early detection and precise prevention among HIV-positive individuals. The articles in this issue focused on the global situation of HIV tracing, and molecular network analysis in promoting accurate detection and prevention of AIDS started from analyzing the reported epidemiological characteristics of HIV/AIDS in Ningbo city from 2017 to 2020. Relations of HIV transmission between HIV positive individuals and sex partners by tracing investigation were also, analyzed. Data on HIV transmission mode by combining social and molecular networks were gathered to provide evidence for applied research on precise detection, prevention, and control of AIDS.

[Analysis on the relationship of molecular transmission between HIV infected men who have sex with men and their sexual partners].

Objective: To investigate the relationship between HIV-infected men who have sex with men and their sexual partners in Zhejiang province. Methods: A cross-sectional survey was conducted to recruit newly confirmed HIV/AIDS among MSM from 2015 to 2017, including sexual partner identification and molecular epidemiological study. Plasma was collected to extract RNA, and the pol gene of HIV-1 was amplified by RT-PCR/nested PCR. Phylogenetic tree and molecular transmission cluster were analyzed to identify the transmission relationship between sexual partners. Results: A total of 937 HIV/AIDS among MSM were recruited to promote HIV testing for their sexual partners, and 173 positive sexual partners were identified. 50.8% (61/120) of the gene sequences were clustered among the positive sex partners. Seven pairs of clustered sex partners combined with the results of recent infection preliminarily determined the transmission direction. In the clusters, there were statistical differences between the partners who were diagnosed in the same year (OR=12.190, 95%CI: 1.563-95.054) or with current residence in the different districts (OR=17.054, 95%CI: 1.742-166.982). Conclusions: Combined with a molecular transmission network, HIV test for the sexual partners of HIV/AIDS among MSM can improve the accurate tracking of cases and preliminarily determine the direction of transmission, according to the results of recent infection. It is suggested that after HIV is confirmed for HIV/AIDS among MSM, HIV tests should be carried out as soon as possible for their sexual partners, including a cross-regional sexual partner tracking test, which is helpful to improve the tracing procedure.

[Analysis on the HIV-1 molecular transmission characteristics of newly confirmed HIV/AIDS in Jiaxing city, 2017-2018].

Objective: To analyze the relationship between infection and transmission of HIV/AIDS, explore the characteristics of the HIV-1 transmission network, and provide evidence for formulating targeted prevention and control measures. Methods: The newly confirmed HIV/AIDS in Jiaxing from 2017 to 2018 were selected for the study. The sociodemographic and infection transmission-related information was gathered. The blood samples were collected and RNA was extracted, RT-PCR and nested PCR amplified the pol gene of HIV-1. The phylogenetic tree was constructed by Mega 6.0 software for subtype analysis. The genetic distance between strains was calculated, and the molecular transmission network was drawn by using Cytoscape 3.6.0 software. The results of the epidemiological study based on the molecular transmission network were analyzed. Results: There were fifteen HIV-1 gene subtypes in 517 cases of HIV/AIDS. The main subtypes were CRF01_AE (37.1%)、CRF07_BC (36.2%) and CRF08_BC (11.8%). Under the 1.0% gene distance threshold, 87 molecular clusters were established, and the total clustering rate was 45.8% (237/517). The cluster risk factors were 60-81 age group (compared with 14-24 age group, OR=2.690, 95%CI:1.058-6.844), married (compared with unmarried, OR=1.698, 95%CI:1.003-2.875), CRF07_BC subtype (compared with CRF01_AE, OR=2.203, 95%CI:1.426-3.404). The largest molecular cluster, CRF07_BC-1, consisted of 50 cases (including 21 cases confirmed in 2017 cases and 29 confirmed in 2018). Multivariate analysis showed that characteristics of unmarried (compared with married, OR=2.482, 95%CI:1.140-5.402), gays (compared with heterosexual, OR=3.163, 95%CI:1.543-6.483), cases with high-risk transmission (compared with other cases, OR=7.631, 95%CI:1.783-32.654), confirmed in Nanhu and Pinghu districts of Jiaxing (compared with other districts, OR=2.225, 95%CI:1.074-4.608) were risks for entering the largest molecular cluster. There were seven suspected high-risk transmission MSM in the largest molecular cluster. The first debut of homosexual behavior was from 2010 to 2018, and the median number of gay partners was 20 (P25, P75：10, 100) within two years before being diagnosed. Six reported a recent history of looking for gay partners in an MSM dating place in Nanhu district. Conclusions: The HIV-1 subtypes of newly confirmed HIV/AIDS were diverse, mainly sporadic in Jiaxing from 2017 to 2018. There were geographical aggregation characteristics and suspected some high-risk transmission cases, suggesting that rapid transmission and targeted intensive intervention are needed.

[Willingness of post-exposure prophylaxis and possible related factors in men who have sex with men].

Objective: To analyze the willingness of post-exposure prophylaxis (PEP) to prevent HIV transmission and related factors in men who have sex with men (MSM). Methods: Cross sectional survey design was used in this study. After informed consent, MSM aged 18 years or above and having had homosexual anal or oral sex in the past 6 months were recruited through "i WeChat" official account between September and November, 2019. Results: Of 1 517 MSM were surveyed, the proportion of MSM who had ever heard of PEP were 72.5% (1 100/1 517) and 87.9%(1 333/1 517) of the MSM said they would like to use PEP if it is needed.Multivariate logistic regression analysis suggested that aged above 25 year (OR=1.807, 95%CI: 1.090-2.995), HIV test history (OR=1.953, 95%CI: 1.171-3.256) and being aware of PEP (OR=2.163, 95%CI: 1.468-3.186) were the positive factors for PEP use, but an aware of the HIV status of sexual partner was the negative factor for PEP (OR=0.602, 95%CI: 0.407-0.890). Among MSM who had ever heard of PEP, the positive factors for PEP use included living in Zhejiang (OR=1.942, 95%CI: 1.097-3.438), aged above 25 years (OR=2.431, 95%CI: 1.331-4.439), being aware of PEP (OR=3.714, 95%CI: 1.532-9.007) obtaining information about PEP service from MSM organization/volunteer/health organization. Conclusions: MSM's willingness to use PEP services was relatively high. Age, awareness of PEP related knowledge, and awareness of sexual partner's HIV infection status were the related factors. MSM organization/volunteer/health organization were the main forces for PEP promotion in MSM.

[Epidemiological characteristic of newly reported HIV/AIDS cases with non-martial and non-commercial heterosexual behaviors in Zhejiang province, 2017-2019].

Objective: To understand the epidemiological characteristics and transmission routes of newly reported HIV/AIDS cases with non-martial and non-commercial (NMNC) heterosexual behaviors in Zhejiang province. Methods: A retrospective survey was conducted among HIV/AIDS cases that had NMNC heterosexual behavior history and diagnosed with HIV infection in Zhejiang between January 1st, 2017 and September 30th, 2019. The multiple correspondence analysis (MCA) was used to explore the association of social demographic characteristics with NMNC heterosexual partner types in the cases. Results: A total of 406 participants with NMNC heterosexual behaviors before HIV diagnoses were recruited in this study. Most of them were males (67.2%, 273/406), aged 25-49 years at HIV diagnoses (59.1%, 240/406). Prior to HIV infection confirmation, 36.0% (146/406) participants only had casual sexual partners, 52.0% (211/406) only had regular sexual partners, and 12.0% (49/406) had both. Statistical differences in marital status, occupation and income level were found among participants with different types of NMNC heterosexual partners (all P<0.05). Result of MCA indicted that monthly income ≤3 000 yuan RMB, self-employed, being married were only associated with casual NMNC heterosexual partner; working in service industry, education level of junior high school were only associated with regular heterosexual partner; working in enterprise, high school education level or above, monthly income ≥5 000 yuan RMB were associated with both casual and regular sexual partner. Conclusion: The HIV/AIDS cases with NMNC heterosexual behaviors before HIV diagnoses accounted for a large proportion in Zhejiang province during 2017-2019. Active intervention efforts should be made to improve the health awareness of the public to reduce the risk behaviors for HIV transmission.

[Analysis of new HIV-1 infection in MSM with seroconversion determined by limiting antigen avidity enzyme immunoassay].

Objective: To evaluate the applicability of limiting antigen avidity enzyme immunoassay (LAg-Avidity EIA, LAg for short) in determining the new HIV-1 infection status of MSM population with seroconversion and make correlation analysis of other biological indicators. Methods: The 15 cases with HIV seroconversion were found in a MSM observation cohort for calculating the HIV prevalence in Zhejiang.The subjects were conducted epidemiological investigation and sampled.The interval of infection time was estimated according to the exposure history and the time of HIV-positive confirmation.LAg, immunoblotting, CD4 cell counting and viral load test were applied in the testing of the related blood samples. McNermar test was conducted for consistency of the two methods. Results: Of 15 cases, the average age was (31.5±8.0) years old, ranging from 24 to 57 years old. The interval of infection time ranged from 40 days to 366 days, and the median was 134 days, with inter-quartile range from 89 to 180 days. A total of 7 cases were classified as new HIV-1 infection by LAg, and 8 cases were classified as chronic infection.The consistent rate was high to 86.67%, and kappa value was 0.73.The samples lacking at least two bands in p31, p51, p66 and gp120 by immunoblotting were determined as recent infection, of which the new infection proportion was significantly higher than that of other samples (P=0.029).There was no statistical difference in the distribution of CD4 counts (P=0.533) and viral loads (P=0.467) between the new infection and chronic infection groups that divided by LAg. Conclusion: By combining with exposure history, the limiting antigen avidity enzyme immunoassay can be used to estimate the new HIV-1 infection.The other biological indicators such as immunoblotting bands, CD4 cell counts and viral loads, can be used as accessory indicators in evaluating the status of new HIV-1 infection.

[Situation of anal sex among low-tier female sex workers in the Demonstration Areas of Comprehensive AIDS Responses in Zhejiang province].

Objective: To analyze the prevalence of anal sex and related factors in low-tier female sex workers (FSWs) in the demonstration areas of comprehensive AIDS responses (DACAR) in Zhejiang province. Method: In 2013, a survey on low-tier FSWs was carried out in 21 Demonstration Areas of AIDS Responses in Zhejiang. Experience of having anal sex with clients in the last month was taken as dependent variable while independent variables would include perception and characteristics related to behavior of the FSWs. The multivariate logistic regression analyses were conducted to identify the factors related to anal sex in low-tier FSWs. Results: A total of 2 645 low-tier FSWs were interviewed. Among these FSWs, 67.9% (1 796/2 645) were over 26 years old, 89.9% (2 378/2 645) were with education level of junior high school or below, 58.4% (1 546/2 645) were married, 78.2% (2 068/2 645) were from other provinces, 68.6% (1 814/2 645) had income level less than 4 000 Yuan, and rates of anal sex with client in the last month were 5.03% (133/2 645). Results from the multivariate logistic regression analysis of related factors of anal sex with client in the last month showed that among the low-tier FSWs, the venues of having commercial sex were in hair salons/massage parlors (OR=7.31, 95%CI: 2.27-23.59), roadside shops (OR=7.89, 95%CI: 2.27- 27.40) or other places (OR=4.65, 95%CI: 1.23-17.53), when compared with the street-women service. FSWs often engaged in commercial sex business in three or more counties (OR=1.68, 95%CI: 1.01-2.81), when compared with FSWs often engaged in commercial sex business just one county. FSWs had sex with only middle-aged and the elderly clients (OR=0.45, 95%CI: 0.30-0.66), when compared with FSWs had sex with young or middle-aged and the elderly clients. FSWs had risk perception for sexually transmitted disease (STD) (OR=2.00, 95%CI: 1.20-3.32), when compared with FSWs with no risk perception. FSWs had oral sex experience with their clients in the last month (OR=7.29, 95%CI: 4.78-11.12), when compared with the ones without oral sex. The above said factors were all related to the incidence of anal sex. Conclusions: Certain numbers of low-tier FSWs had anal sex experiences with their clients, especially those who had oral sex were more likely to have anal sex in DACAR in Zhejiang province. Attention should be paid to anal sex behavior when conducting behavior-related intervention programs, targeting on the low-tier FSWs.

[Characteristics of subtypes and transmission of HIV-1 infected persons among student MSM in Zhejiang province, 2013-2015].

Objective: To investigate the characteristics of subtype diversity and transmission on HIV-1 among 12 to 30 years old student MSM in Zhejiang province. Methods: A total of 290 newly diagnosed HIV infected student MSM were selected as the research objects for molecular studies on HIV, in Zhejiang province during 2013 to 2015. Data on epidemiology and plasma samples of these people were collected. HIV-1 nucleotide sequences of pol gene regions were amplified using the RT-PCR/nested PCR method and sequenced. Phylogenetic analysis was performed to determine the HIV-1 genotypes. Characteristics of transmission mode among these cases were also analyzed. Results: A total of 290 cases, 50.3% were diagnosed in Hangzhou and 81.0% had college or above degrees. 178 sequences including 10 subtypes, were obtained, with the main subtypes as CRF01_AE (49.4%, 88/178) and CRF07_BC (39.3%, 70/178). A total of 18 molecular transmission clusters were formed (42 cases, cluster size from 2 to 4), with the proportions of clusters as 23.6% (42/178). 61.9% (26/42) of student MSM with their schools located in the same district within the transmission clusters. Their sexual partners would include both student MSM and non-student MSM. The proportion of clusters among middle school students was 38.2% (13/34), higher than that of college students (20.1%, 29/144) ( χ(2)=4.996, P<0.05). Conclusions: The HIV-1 subtypes of student MSM in Zhejiang province appeared diversity, which indicated with the diversity of sources of infection. The geographical distribution of cluster cases is relatively centralized. In order to effectively control the spread of AIDS, more attention should be paid to the sexual partners involved and to specific programs on intervention.

[Analysis on the transmission characteristics of newly reported human immunodeficiency virus/acquired immunodeficiency syndrome cases based on the molecular transmission network in Huzhou, Zhejiang, 2017].

Objective: Using field epidemiological investigation and molecular analysis to construct the molecular transmission network of human immunodeficiency virus/acquired immunodeficiency syndrome cases (HIV/AIDS) newly diagnosed in Huzhou in 2017, Zhejiang Province. Methods: A total of 160 participants were obtained through a web-based system from Chinese Center for Disease Control and Prevention (CCDC) with the features of diagnosed in Huzhou in 2017 who also had been collected samples for the first follow-up. The basic information of demographic characteristics and risk factors was extracted from the website. RNA was extracted from plasma samples of untreated cases, followed by RT-PCR and nest-PCR for pol gene amplification, sequencing. Phylogenetic tree was constructed by MEGA software for HIV gene subtyping. TN93 model was used for calculating the distance between two sequences. Cytoscape software was used for drawing molecular transmission network. And then an epidemiological survey was conducted to cases in the primary cluster. Results: A total of 138 sequenced individuals (86.3%) were acquired from 160 individuals. Among which, 123 (89.1%) were male. The highest proportion of subtype was CRF07_BC (60, 43.5%), followed by CRF01_AE (46, 33.3%), and with four cases of Unique Recombinant Form (URF, CRF01_AE and CRF07_BC) and one case of URF (subtype B and C). A total of 18 molecular clusters included 56 individuals (40.6%) were found in the transmission network under the optimal genetic distance threshold (1.0%). The clustering proportion of CRF07_BC (66.1%, 37 cases) was higher than that of CRF01_AE. There were 9 clusters formed among CRF07_BC, including 37 cases (accounting for 61.7%, 37/60). The primary transmission cluster contained 11 cases, among which 9 cases were transmitted by homosexual sex. The first time of the cases to have homosexual behavior is range from 2010 to 2016, whose media number (P(25), P(75)) of partners was 6 (3.5, 8.5). Most of the cases come from Anhui Province and engaged in garment industry (5 cases), between which there were 8 cases used Blued software to seek for casual partners, 1 case seeking for casual partners in garden. Conclusion: With CRF07_BC and CRF01_AE predominantly circulating, HIV genetic diversity had been noticed in this area. The primary cluster was consisted of high proportion of locally new infections, and a specific population aggregation in limited place existed.

[Status and associatied factors of anal sexual intention in casual sex behavior among heterosexual college students in Zhejiang Province].

Objective: To identify the status and risky factors of anal sexual intention in casual sex behavior in Zhejiang province. Methods: Stratified cluster sampling was conducted among college students in 13 colleges in 11 cities between October to November, 2018. 482 students were enrolled who self-reported "heterosexuality "and" ever had casual sex behavior". A self-designed network questionnaire was complimented containing basic information, knowledge of HIV, sexual behavior. Chi-square test was used to compared the difference of anal sex intention between different characteristic. The multivariate logistic regression methods was used to analyze the influence factors. Results: Among 482 students, the age was (20±1.442) years old. And 87.3% (421) were male and 29.0% (140) were from other province. The rate of anal sex intention were 19.4% (94/482) in total, with the rates of 38.1% (24/63) and 14.4% (53/367) in students with sexual number more than 5 and less than 5 (P<0.001), separately. Compared with students searching casual sexual partner with non-internet access (17.0%, 16/201), students searching sexual partner with internet access had higher risk of anal sex practice (27.8%, 78/281) (P<0.001). The rate of anal sex practice among students reporting "ever had casual sex after drinking "and" never had casual sex after drinking" were 30.5% (64/210) and 9.4% (25/266) (P<0.001). The multivariate logistic regression results revealed that compared with students searching casual sexual partner with non-internet access and reporting "never had casual sex after drinking", subjects searching sexual partner with internet access(OR (95%CI)=2.65 (1.34-5.23)) and "ever had casual sex after drinking" OR (95%CI)=3.02 (1.65-5.33) were more likely had higher risk of anal sex practice. Conclusion: Heterosexual college students in Zhejiang Province tend to have anal intercourse with causal sexual partners. Searching for causal sexual partners on internet or mobile phone dating software and having temporary sexual behavior after drinking were correlated factors.

[HIV infection status and characteristics of non-remunerated blood donors in Hangzhou, 2008-2017].

Objective: To understand HIV infection status and characteristics of non-remunerated blood donors in Hangzhou. Methods: HIV antibody test were conducted for non-remunerated blood donors in Hangzhou and their demographic and epidemiological information were collected from 2008-2017. χ(2) test for trend (liner by liner association chi square test) was used for the comparison of the HIV infection trends in each year. Results: A total of 1 461 129 non-remunerated blood donors were surveyed in Hangzhou during 2008-2017, and 260 blood donors were HIV positive. Most HIV infected blood donors were males (96.5%, 251/260) and aged 18-34 years (72.7%, 189/260). Among 260 HIV positive blood donors, those reporting repeated non-remunerated blood donation accounted for 36.9% (96/260), those reporting homosexual transmission accounted for 53.5% (139/260) and those reporting heterosexual transmission accounted for 44.6% (116/260). The HIV infected persons reporting homosexual behaviors were mainly aged 18-34 years (82.0%, 114/139) and unmarried (71.2%, 99/139). Most HIV infected students reported homosexual transmission (88.4%, 23/26). The crude HIV positive rate was 0.8/10 000-2.5/10 000, the differences in annual HIV positive rate had no significance (trend χ(2)=2.355, P=0.125). The crude HIV positive rate in male blood donors aged 18-24 years increased from 1.1/10 000 in 2008 to 3.7/10 000 in 2017, the difference was significant (trend χ(2)=5.175, P=0.023). Standardized HIV positive rate was 0.9/10 000-2.4/10 000. Conclusions: HIV infection rate was low in non-remunerated blood donors in Hangzhou during 2008-2017. Most HIV infected persons were males and aged 18-34 years. Heterosexual and homosexual contacts were the major transmission routes. The HIV positive rate in males aged 18-24 years showed an increase trend.

[Analysis of oral sexual behavior and related factors among male students from college graduation in Hangzhou].

Objective: To study oral sexual behavior and related factors among male students. Methods: The male students from college graduation in Hangzhou were selected as the study objects, and the inclusion criteria were having had sex and informed the type of behavior. A total of 490 subjects were finally included. Results: Among 490 male students, the 20-22 years old, 23 years old and 24-27 years old age groups accounted for 38.8% (n=190), 37.8% (n=185) and 23.3% (n=114), respectively. A total of 99 (20.2%) cases had oral sexual behavior, of which only 14 (2.9%) cases used condom. After adjusting for unplanned pregnancy, stage of sexual behavior, sexually transmitted diseases infection possibility, sexual orientation factors, normal/unnormal family relationship, more than 2 sexual partners, casual sexual partners, sexual partners from other college, sexual partners from society, sexual behavior in past 1 year were positively associated with oral sexual behavior. The corresponding OR (95%CI) values were 2.77 (1.40-5.50), 2.29 (1.27-4.15), 2.68 (1.23-5.88), 2.45 (1.34-4.48), 2.47 (1.15-5.33) and 2.04 (1.05-3.96), respectively. Use of condoms was negatively associated with oral sexual behavior, the OR (95%CI) value was 0.20 (0.09-0.42). Conclusion: Normal/unnormal family relationship, more than two sexual partners, casual sexual partners, sexual partners from other college, sexual partners from society, sexual behavior in last one year and condom use in each vaginal sexual behavior were associated with oral sexual behavior.