OBJECTIVEThe migrant population is a vulnerable group for HIV infection in China. Understanding potential epidemic trends among migrants is critical for developing HIV preventative measures in this population.

METHODSThe Estimation and Projection Package (EPP) model was used to process prefecture and county-level surveillance data to generate HIV prevalence and epidemic trends for migrant populations in China.

RESULTSThe prevalence of HIV among migrants in 2009 was estimated at 0.075% (95% CI: 0.042%, 0.108%) in China. The HIV epidemic among migrants is likely to increase over the next 5 years, with the prevalence expected to reach 0.110% (95% CI: 0.070%, 0.150%) by 2015.

CONCLUSIONAlthough the 2009 estimates for the HIV/AIDS epidemic in China indicate a slower rate of increase compared with the national HIV/AIDS epidemic, it is estimated to persistently increase among migrants over the next 5 years. Migrants will have a strong impact on the overall future of the HIV epidemic trend in China and evidence-based prevention and monitoring efforts should be expanded for this vulnerable population.

China ; epidemiology ; Condoms ; Epidemics ; statistics & numerical data ; Female ; HIV Infections ; epidemiology ; Humans ; Male ; Models, Theoretical ; Prevalence ; Risk Factors ; Safe Sex ; Sexual Behavior ; Transients and Migrants

Objective To understand the trends on HIV and syphilis infections,as well as on risk behaviors and intervention among MSM in China from 2010 to 2013 so as to provide information for the development of intervention strategies for MSM. Methods Study population involved MSM who were recruited for the national HIV sentinel surveillance between 2010 and 2013. Demographic information,HIV related risk behaviors,and results on HIV and syphilis infections were described and trend analysis was performed. Results Between 2010 and 2013,the total number of MSM under survey was 149 848. As for sources of the studied population,12.3% of them were from public bathrooms (Group A),30.1% from internet (Group B),and 57.5% were others (Group C). Proportions of three groups were similar between 2010 and 2013. The proportion of always using condom in the last six months increased from 30.2%to 37.8%,from 34.7%to 42.9%and from 35.3%to 43.1%in group A,B or C( trend:P<0.01),from 2010 to 2013. The proportion of using condom in group A was the lowest among the three groups. The prevalence rate of HIV increased from 7.8%in 2010 to 9.2%in 2013 among group A,from 5.0%in 2010 to 6.8%in 2013 among group B,from 5.6%in 2010 to 6.5%in 2013 among group C(trend:P<0.01). The prevalence rate of syphilis decreased from 13.2% in 2010 to 9.5% in 2013 among group A,from 6.1% in 2010 to 5.7% in 2013 among group B,from 8.7% in 2010 to 6.2% in 2013 among group C (trend:P<0.01). In this MSM population,77.1%of them were at age 21-40,9.4%were at age 41-50 and 2.8%were older than 50 years of age. Both the prevalence rates of HIV and syphilis were the highest-10.1%and 13.6%,among age group of over 50s,respectively. Conclusion HIV prevalence among MSM increased rapidly in the last four years,especially in older age groups and from public bathrooms. More intervention efforts should be targeting on MSM with the above mentioned characters.

Objective To analyze the characteristics on demographical,spatial distribution and transmission mode of HIV infections among 50-year-old population.Methods Related information on demography,spatial distribution,high risk behavioral and history of HIV infections among 50-year-old population were collected and analyzed.Possible time of infection based on their first CD4 testing results right after the HIV diagnoses,was estimated.Results Since 2008,the number of new HIV/AIDS cases among the over-50-year-olds was reported increasing annually.The number of aged 50 and above in 2014 was 4.2 times than the number in 2008.50-year-old or older population were infected mainly through heterosexual behavior (88.0％).Among these cases,83.9％ self-reported as having histories on extramarital sex intercourse and the number was increasing yearly.Among male cases who admitted as having heterosexual experience,95.1％ of them reported as having histories of extramarital sex intercourse while 53.4％ of the female cases reported as having the same experiences.46.6％ of spouses of the females or with fixed partners were HIV positive.Through estimating the time of infection and the time interval between infection and diagnosis,we found that the proportion was 15.5％,from infection to diagnosis as 3 years among the 50 and older age groups,but the proportion of 8 years from infection to diagnosis was 43.6％.We estimated that 66.5％ of the new HIV cases who were at age 50 and over,were infected when they were at that age span.The average time from infection and being tested was (6.8 ± 2.7) years.Conclusion The increasing number of being diagnosed on HIV among the 50-year-olds population might be related to both high risk exposure and belated diagnoses among this population,calling for the necessity of deriving the sources of HIV infection and tailoring the HIV prevention strategies in this population.

Objective To compare the prevalence of HIV/STD and related health care seeking behaviors among male STD clinic attendees between Xi'an and Xianyang cities.Methods During June and July 2016,206 male STD clinic attendees were studied in Xi'an city,with another 221 male STD clinic attendees in Xianyang city.Cross-sectional questionnaire survey was used to collect attendees' behavioral information.Blood samples were collected via HIV/HCV/Syphilis testing.Results The prevalence rate of HIV infection was 2.4％ (5/206) in Xi'an and 0.9％ (2/221) in Xianyang,with no statistical significant difference between the two cities.The prevalence rate of syphilis was 4.9％ (10/206) in Xi'an,which was significantly lower than 13.6％ (30/221) in Xianyang.The proportion of respondents,diagnosed with other sexually transmitted diseases,in Xi'an was higher than that of Xianyang.The proportions of commercial heterosexual sex and sex with temporary sexual partners in the past 3 months were 18.0％ (37/206) and 15.5％ (32/206) in Xi'an,lower than 46.6％ (103/221) and 15.8％ (35/221) in Xianyang (x2 =39.70,P ＜0.01;x2 =-0.01,P=0.93).The proportions of condom use with commercial sex workers or temporary sexual partners in the past 3 months among Xi'an were 37.8％ (14/37) and 6.3％ (2/32),lower than 93.1％ (95/102)and 57.1％ (20/35) in Xianyang (x2=49.06,P＜0.01;x2=19.63,P＜0.01).Conclusion Differences were noticed between Xi'an and Xianyang city in terms of STD and HIV prevalences,behaviors related to commercial sex and use of condoms among the male STD clinic attendees that calling for targeted actions in control of high risk behaviors in both HIV/AIDS and STDs transmission.

Objective To analyze the serological results and sexual behavior among different types of drug users (DUS) at the HIV sentinel surveillance sites.Methods Sentinel surveillance programs were conducted between April and June annually.DUS were those involved in custodies,living at the communities and those attending the methadone maintenance treatment clinics but with positive urine tests one month before blood sampling collected and questionnaire survey started.Results 116 279 drug abusers were included in the analysis.The prevalence rates of HIV,Syphilis and HCV among traditional drug(heroin,etc.)users were 5.0％,4.4％ and 49.4％,while the prevalence rates of new narcotic (meth,etc.) users were 0.5％,4.6％,15.2％,respectively.The prevalence rates of HIV,syphilis among traditional drug uses were higher than the new narcotic users (P＜0.01).The proportion of sexual behavior in last month and the proportion of sexual behavior with casual and commercial sexual partners were 46.3％,87.2％ and 28.1％ among the new narcotic users,respectively,which were higher than those among traditional drug users (40.7％,82.8％ and 22.2％).The proportion of using condom in last sexual contact with casual sexual partner was 33.3％ among the new narcotic users which was less than traditional drug users (36.2％).The proportion of condom use in the last commercial sexual contact was 65.l％ which was higher than those traditional drug users (62.9％).The proportion of never using condom with casual and commercial sexual partners in the past year was 43.2％ and 19.0％ among the traditional drug users,which were higher than those among new narcotic users (41.3％,15.3％).Conclusion Compared with the traditional drug abusers,the sexual behavior of new narcotic users seemed more active,less engaging in condom use but with higher risk of HIV transmission through sexual contact.

Objective To understand the epidemiological characteristics and changing patterns of HIV transmission through heterosexual contact since 2008,and to project the influences of heterosexual transmission mode on the HIV epidemic in China.Methods Demographic data and history of exposure in newly identified HIV/AIDS cases aged 15 years or older,through heterosexual transmission mode from 2008 to 2014,were collected and analyzed.Results The number of HIV/AIDS cases caused by heterosexual transmission increased from 23 402 in 2008,to 68 671 in 2014.The proportion of heterosexual transmission mode increased from 8.7％ in 2008 to 66.4％ in 2014.Among these cases,the proportion of males increased from 55.3％ in 2008 to 68.2％ in 2014.Among those who reported acquiring HIV through heterosexual contact,the proportion of cases through extra-marital sexual acts out of all the newly report ones,increased from 78.2％ in 2008 to 88.2％ in 2014.This mode of infection accounted for 85.2％ in the age 15 to 49 years group,comparing to 84.2％ in the age group of 50 years old or above.The proportion of reported HIV infections through extra-marital sexual acts appeared 93.8％ on males while 69.0％ on females,with statistically significant difference (x2=36 000.000,P＜0.001).Conclusion As the predominant factor of HIV/AIDS epidemic,currently in China,heterosexual transmission showed diversities in different sub-epidemic areas,gender or age groups.Tailored strategies were urgently needed for health education and high-risk behavioral intervention,according to the local epidemic driven factors,respectively.

Objective To analyze the factors of people living with HIV/AIDS and mobility in 2013 who were reported before 2012 in China.Methods Data were collected through China HIV/AIDS case reporting information system in 2012 and 2013.A total of 300 349 HIV/AIDS cases reported before 2012 have been included in this study and have been visited in 2013.SPSS software was used to conduct multivariate logistic regression model.Results A total of 300 349 HIV/AIDS cases have been included in the study and 5.4% ( 16 088/300 349 ) objects have changed their residential locations in 2013.The movements mostly happened inside local province , which accounted for 69.1% ( 11 114/16 088 ).In Yunnan,Guangdong,and Guangxi province,the mobile percentage were 85.8% (2 377/2 771),58.5%(1 534/2 621) and 78.1% (1 470/1 883) that movements happened inside local province.Multivariate logistic regression analysis showed that male (12 478 cases,OR=1.97,95%CI:1.03-1.12),HIV infection (12 125 cases,OR=1.99,95%CI:1.92-2.0),15-49 age group (15 144 cases,OR=2.16,95%CI:2.00-2.32) were more mobile.Conclusion The movements mostly happened inside local province in 2013 in China and population movements tends to happen in young men infected with HIV .

Objective To characterize the migration patterns of men who have sex with men (MSM) living with HIV/AIDS in the period 2008-2015 and to characterize the determinants of their migration.Methods All identified HIV/AIDS cases transmitted through self-reported homosexual contact reported to the National Case Reporting System(CRS) by the end of December 31,2015 were included in this study.Data of basic demographic characteristics,household registration and address of the research objects were collected.Retrospective cohort study was used to analyze the migration characteristics of HIV/AIDS cases between 2008 and 2015.We used the x2 test to analyze their migration patterns and epidemiological characteristics,and multilevel logistic regression to investigate the determinants of migration.Results While mobile cases comprised 46.1％ of the sample (n=54 714),we detected a significant rising trend (x2=130.93,P＜0.001) as this proportion rose from 42.0％ (1 335/3 182) in 2008 to 47.9％ (15 623/32 610)in 2015.Of the 13 580 mobile cases with Hukou registration in Eastern China,89.8％ (12 201) migrated to other parts of Eastern China.Meanwhile,52.0％ of the 26 088 cases registered in Central China (n=13 570)and 30.5％ of the 14 106 registered in Western China (n=4 298) migrated to Eastern China.Furthermore,96.2％ of mobile cases (n=52 627) resided in the urban areas,of which 40.8％ (n=21 452) migrated from rural areas to urban areas and 58.4％ (n=30 722) migrated between urban areas.The annual proportion of cases who changed their address within 1 year of diagnosis ranged from 12.0％-18.5％.The results of the multilevel model showed that cases who were aged 25-49 years (OR=1.30,95％CI:1.26-1.34),single (OR=1.95,95％CI:1.87-2.02),and had a high school education or above (OR=1.68,95％CI:1.64-1.73)were more likely to migrate.AIDS (OR=0.71,95％CI:0.69-0.74),Hukou registration in an urban area (OR=0.63,95％CI:0.61-0.65),in Central China (OR=0.84,95％CI:0.73-0.97),Western China (OR=0.75,95％CI:0.64-0.87),and in regions with a high population density or above-average gross domestic product (GDP) per head (OR=0.77,95％ CI:0.69-0.87 and OR=0.70,95％ CI:0.62-0.79,respectively) were negatively associated with migration.Conclusion The number and proportion of mobile HIV cases showed a rising annual trend.Age,marital status,level of education and disease severity,in addition to the population density and level of economic development of cases' place of origin,were significant determinants of migration.

Objective To analyze the factors of people living with HIV/AIDS and mobility in 2013 who were reported before 2012 in China.Methods Data were collected through China HIV/AIDS case reporting information system in 2012 and 2013.A total of 300 349 HIV/AIDS cases reported before 2012 have been included in this study and have been visited in 2013.SPSS software was used to conduct multivariate logistic regression model.Results A total of 300 349 HIV/AIDS cases have been included in the study and 5.4% ( 16 088/300 349 ) objects have changed their residential locations in 2013.The movements mostly happened inside local province , which accounted for 69.1% ( 11 114/16 088 ).In Yunnan,Guangdong,and Guangxi province,the mobile percentage were 85.8% (2 377/2 771),58.5%(1 534/2 621) and 78.1% (1 470/1 883) that movements happened inside local province.Multivariate logistic regression analysis showed that male (12 478 cases,OR=1.97,95%CI:1.03-1.12),HIV infection (12 125 cases,OR=1.99,95%CI:1.92-2.0),15-49 age group (15 144 cases,OR=2.16,95%CI:2.00-2.32) were more mobile.Conclusion The movements mostly happened inside local province in 2013 in China and population movements tends to happen in young men infected with HIV .

Objective To characterize the migration patterns of men who have sex with men (MSM) living with HIV/AIDS in the period 2008-2015 and to characterize the determinants of their migration.Methods All identified HIV/AIDS cases transmitted through self-reported homosexual contact reported to the National Case Reporting System(CRS) by the end of December 31,2015 were included in this study.Data of basic demographic characteristics,household registration and address of the research objects were collected.Retrospective cohort study was used to analyze the migration characteristics of HIV/AIDS cases between 2008 and 2015.We used the x2 test to analyze their migration patterns and epidemiological characteristics,and multilevel logistic regression to investigate the determinants of migration.Results While mobile cases comprised 46.1％ of the sample (n=54 714),we detected a significant rising trend (x2=130.93,P＜0.001) as this proportion rose from 42.0％ (1 335/3 182) in 2008 to 47.9％ (15 623/32 610)in 2015.Of the 13 580 mobile cases with Hukou registration in Eastern China,89.8％ (12 201) migrated to other parts of Eastern China.Meanwhile,52.0％ of the 26 088 cases registered in Central China (n=13 570)and 30.5％ of the 14 106 registered in Western China (n=4 298) migrated to Eastern China.Furthermore,96.2％ of mobile cases (n=52 627) resided in the urban areas,of which 40.8％ (n=21 452) migrated from rural areas to urban areas and 58.4％ (n=30 722) migrated between urban areas.The annual proportion of cases who changed their address within 1 year of diagnosis ranged from 12.0％-18.5％.The results of the multilevel model showed that cases who were aged 25-49 years (OR=1.30,95％CI:1.26-1.34),single (OR=1.95,95％CI:1.87-2.02),and had a high school education or above (OR=1.68,95％CI:1.64-1.73)were more likely to migrate.AIDS (OR=0.71,95％CI:0.69-0.74),Hukou registration in an urban area (OR=0.63,95％CI:0.61-0.65),in Central China (OR=0.84,95％CI:0.73-0.97),Western China (OR=0.75,95％CI:0.64-0.87),and in regions with a high population density or above-average gross domestic product (GDP) per head (OR=0.77,95％ CI:0.69-0.87 and OR=0.70,95％ CI:0.62-0.79,respectively) were negatively associated with migration.Conclusion The number and proportion of mobile HIV cases showed a rising annual trend.Age,marital status,level of education and disease severity,in addition to the population density and level of economic development of cases' place of origin,were significant determinants of migration.