Limits...
Sexual risk factors for HIV infection in early and advanced HIV epidemics in sub-Saharan Africa: systematic overview of 68 epidemiological studies.

Chen L, Jha P, Stirling B, Sgaier SK, Daid T, Kaul R, Nagelkerke N, International Studies of HIV/AIDS (ISHA) Investigato - PLoS ONE (2007)

Bottom Line: We used random-effects methods and stratified results by gender, time, background HIV prevalence rates and other variables.These risks changed little over time and stratification by lower and higher HIV background prevalence showed that risk ratios for most variables were larger in high prevalence settings.Even in high prevalence settings, prevention among people with high rates of partner change, such as female sex workers and their male clients, is likely to reduce transmission overall.

View Article: PubMed Central - PubMed

Affiliation: Centre for Global Health Research, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.

ABSTRACT

Background: It is commonly assumed that sexual risk factors for heterosexual HIV transmission in sub-Saharan Africa, such as multi-partner sex, paid sex and co-infections, become less important as HIV epidemics mature and prevalence increases.

Methods and findings: We conducted a systematic review of 68 African epidemiological studies from 1986 to 2006 involving 17,000 HIV positive adults and 73,000 controls. We used random-effects methods and stratified results by gender, time, background HIV prevalence rates and other variables. The number of sex partners, history of paid sex, and infection with herpes simplex virus (HSV-2) or other sexually-transmitted infections (STIs) each showed significant associations with HIV infection. Among the general population, the odds ratio (OR) of HIV infection for women reporting 3+ sex partners versus 0-2 was 3.64 (95%CI [2.87-4.62]), with similar risks for men. About 9% of infected women reported ever having been paid for sex, versus 4% of control women (OR = 2.29, [1.45-3.62]). About 31% of infected men reported ever paying for sex versus 18% of uninfected men (OR = 1.75, [1.30-2.36]). HSV-2 infection carried the largest risk of HIV infection: OR = 4.62, [2.85-7.47] in women, and OR = 6.97, [4.68-10.38] in men. These risks changed little over time and stratification by lower and higher HIV background prevalence showed that risk ratios for most variables were larger in high prevalence settings. Among uninfected controls, the male-female differences in the number of sex partners and in paid sex were more extreme in the higher HIV prevalence settings than in the lower prevalence settings.

Significance: Multi-partner sex, paid sex, STIs and HSV-2 infection are as important to HIV transmission in advanced as in early HIV epidemics. Even in high prevalence settings, prevention among people with high rates of partner change, such as female sex workers and their male clients, is likely to reduce transmission overall.

Show MeSH

Related in: MedlinePlus

HSV-2by lower and higher background HIV prevalence. Notes:* Heterogeneity is tested by chi-square (p<0.05 indicates a significant heterogeneity). The size of the square is proportional to the weight of the respective OR. Different scales are used for HSV-2 studies
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC1994584&req=5

pone-0001001-g006: HSV-2by lower and higher background HIV prevalence. Notes:* Heterogeneity is tested by chi-square (p<0.05 indicates a significant heterogeneity). The size of the square is proportional to the weight of the respective OR. Different scales are used for HSV-2 studies

Mentions: Figure 4, 5 and 6 provide results for studies documenting 3 or more sex partners versus 0–2, history of STI, and HSV-2 infection, grouped by lower and higher antenatal clinic prevalence (as a proxy for background prevalence). While the analyses used a 20% prevalence to delineate the comparison groups, the actual mean background prevalence varied as shown. For women, there were no significant differences in risk of HIV infection with 3 or more sex partners versus 0–2 between lower (OR = 3.65) and higher (OR = 3.63) background HIV prevalence. Similarly, there were few differences in risk of HIV with STI history between lower (OR = 2.35) and higher (OR = 2.41) background HIV prevalence. Finally, there was no major difference in risk of HIV with HSV-2 infection between lower (OR = 4.27) and higher (OR = 5.97) background HIV prevalence, although the comparisons are limited because only two heterogeneous studies were included in higher prevalence settings.


Sexual risk factors for HIV infection in early and advanced HIV epidemics in sub-Saharan Africa: systematic overview of 68 epidemiological studies.

Chen L, Jha P, Stirling B, Sgaier SK, Daid T, Kaul R, Nagelkerke N, International Studies of HIV/AIDS (ISHA) Investigato - PLoS ONE (2007)

HSV-2by lower and higher background HIV prevalence. Notes:* Heterogeneity is tested by chi-square (p<0.05 indicates a significant heterogeneity). The size of the square is proportional to the weight of the respective OR. Different scales are used for HSV-2 studies
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC1994584&req=5

pone-0001001-g006: HSV-2by lower and higher background HIV prevalence. Notes:* Heterogeneity is tested by chi-square (p<0.05 indicates a significant heterogeneity). The size of the square is proportional to the weight of the respective OR. Different scales are used for HSV-2 studies
Mentions: Figure 4, 5 and 6 provide results for studies documenting 3 or more sex partners versus 0–2, history of STI, and HSV-2 infection, grouped by lower and higher antenatal clinic prevalence (as a proxy for background prevalence). While the analyses used a 20% prevalence to delineate the comparison groups, the actual mean background prevalence varied as shown. For women, there were no significant differences in risk of HIV infection with 3 or more sex partners versus 0–2 between lower (OR = 3.65) and higher (OR = 3.63) background HIV prevalence. Similarly, there were few differences in risk of HIV with STI history between lower (OR = 2.35) and higher (OR = 2.41) background HIV prevalence. Finally, there was no major difference in risk of HIV with HSV-2 infection between lower (OR = 4.27) and higher (OR = 5.97) background HIV prevalence, although the comparisons are limited because only two heterogeneous studies were included in higher prevalence settings.

Bottom Line: We used random-effects methods and stratified results by gender, time, background HIV prevalence rates and other variables.These risks changed little over time and stratification by lower and higher HIV background prevalence showed that risk ratios for most variables were larger in high prevalence settings.Even in high prevalence settings, prevention among people with high rates of partner change, such as female sex workers and their male clients, is likely to reduce transmission overall.

View Article: PubMed Central - PubMed

Affiliation: Centre for Global Health Research, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.

ABSTRACT

Background: It is commonly assumed that sexual risk factors for heterosexual HIV transmission in sub-Saharan Africa, such as multi-partner sex, paid sex and co-infections, become less important as HIV epidemics mature and prevalence increases.

Methods and findings: We conducted a systematic review of 68 African epidemiological studies from 1986 to 2006 involving 17,000 HIV positive adults and 73,000 controls. We used random-effects methods and stratified results by gender, time, background HIV prevalence rates and other variables. The number of sex partners, history of paid sex, and infection with herpes simplex virus (HSV-2) or other sexually-transmitted infections (STIs) each showed significant associations with HIV infection. Among the general population, the odds ratio (OR) of HIV infection for women reporting 3+ sex partners versus 0-2 was 3.64 (95%CI [2.87-4.62]), with similar risks for men. About 9% of infected women reported ever having been paid for sex, versus 4% of control women (OR = 2.29, [1.45-3.62]). About 31% of infected men reported ever paying for sex versus 18% of uninfected men (OR = 1.75, [1.30-2.36]). HSV-2 infection carried the largest risk of HIV infection: OR = 4.62, [2.85-7.47] in women, and OR = 6.97, [4.68-10.38] in men. These risks changed little over time and stratification by lower and higher HIV background prevalence showed that risk ratios for most variables were larger in high prevalence settings. Among uninfected controls, the male-female differences in the number of sex partners and in paid sex were more extreme in the higher HIV prevalence settings than in the lower prevalence settings.

Significance: Multi-partner sex, paid sex, STIs and HSV-2 infection are as important to HIV transmission in advanced as in early HIV epidemics. Even in high prevalence settings, prevention among people with high rates of partner change, such as female sex workers and their male clients, is likely to reduce transmission overall.

Show MeSH
Related in: MedlinePlus