Condom and nonoxynol-9 use and the incidence of HIV infection in serodiscordant couples in Zambia. Evidence of marked sexual behavior change associated with low HIV-1 seroconversion in 149 married couples with discordant HIV-1 serostatus: experience at an HIV counselling center in Zaire. HIV infection in sexual partners of HIV-seropositive patients with hemophilia. Heterosexual transmission of HIV by haemophiliacs. No seroconversions among steady sex partners of methadone-maintained HIV-1-seropositive injecting drug users in New York City. Risk of human immunodeficiency virus transmission from heterosexual adults with transfusion-associated infections. Man-to-woman sexual transmission of HIV: longitudinal study of 343 steady partners of infected men. Heterosexual transmission of HIV in Haiti. Evaluation of heterosexual partners, children, and household contacts of adults with AIDS. Antiretroviral treatment of men infected with human immunodeficiency virus type 1 reduces the incidence of heterosexual transmission. Italian Study Group on HIV Heterosexual Transmission. Heterosexual transmission of human immunodeficiency virus type 1 from transfusion recipients to their sex partners. A longitudinal study of human immunodeficiency virus transmission by heterosexual partners. European Study Group on Heterosexual Transmission of HIV. Effect of serotesting with counselling on condom use and seroconversion among HIV discordant couples in Africa. Documented male-to-female transmission of HIV-1 after minimal vaginal exposure in the absence of other cofactors for infection.
We aimed to measure the effectiveness of latex condoms and of nonoxynol-9 [N-9] spermicides, in preventing HIV transmission in heterosexual serodiscordant couples in Lusaka. Each couple was examined at clinic visits scheduled at 3-month intervals for one year or more per couple, or until seroconversion or discontinuation. Couples were given condoms and their choice of 3 N-9 products and advised to use both at every intercourse. Sexual exposure was ascertained from coital logs that recorded coitus and barrier method use. HIV serological testing was done at each clinic visit (ELISA and Western blot if positive). One hundred and ten discordant couples were followed for a mean of 17.6 months. Seventy-eight per cent of coital episodes were protected by condoms, 85% by spermicides and 6.4% were unprotected. Fourteen seroconversions occurred (8.7 infections per 100 couple-years [c-y]). The rate was higher among seronegative men than seronegative women. Among couples who reported using condoms at every intercourse the infection rate was 2.3/100 c-y, compared with 10.7/100 c-y among couples using condoms less consistently (rate ratio [RR] 0.2; 95% confidence interval [CI] 0-1.6). Among couples who reported using N-9 at every intercourse, the seroconversion rate was 6.9/100 c-y; among couples who reported less than full-time N-9 use, the rate was 8.9/100 c-y (RR 0.8; 95% CI 0.2-2.8). Among the subset of female seronegatives, the N-9 RR was 0.5 (95% CI 0.1-3.8). But when we calculated HIV rates according to N-9 consistency in coital acts when condoms were not used, there was no evidence of protection with higher N-9 use. Consistent use of latex condoms reduces the incidence of HIV infection, but the association between N-9 spermicides and HIV is less clear. The current study could not provide compelling data on the impact of N-9 spermicide use on risk of HIV infection. The study's small size, as well as the consistency of concurrent condom use, limited our inferences. Available spermicide products must be studied further. To determine the effect of an HIV-1 counselling program on 149 married Zairian couples with discordant HIV-1 serology, the rates of HIV-1 seroconversion and reported condom utilization have been observed during 382.4 person-years of follow-up (minimum follow-up time per couple of 6 months). Before determination of HIV-1 serostatus and counselling, less than 5% of these couples had ever used a condom. One month after notification of HIV-1 serostatus and counselling, 70.7% of couples reported using condoms during all episodes of sexual intercourse. At 18 months follow-up, 77.4% of the 140 couples still being followed reported continued use of condoms during all episodes of sexual intercourse. At the time of notification of HIV-1 serostatus, 18 couples experienced acute psychological distress. Home-based counselling by trained nurses resolved these difficulties in all but three couples who subsequently divorced. Intensive counselling following notification of HIV-1 serostatus led to low rates of HIV-1 seroconversion (3.1% per 100 person-years of observation) in Zairian married couples with discordant HIV-1 serostatus who voluntarily attended an HIV counselling center. nan nan To assess the incidence of heterosexual HIV-1 transmission from seropositive methadone-maintained injecting drug users (IDU) to their seronegative, non-IDU steady sex partners.
                A prospective, longitudinal study.
                HIV-1-seropositive IDU and their HIV-1-seronegative, non-IDU steady sex partners were recruited from six methadone-maintenance clinics in the New York City boroughs of Brooklyn and Manhattan.
                Between December 1988 and October 1991, 60 research participants were recruited [30 methadone-maintained, HIV-1-seropositive IDU (index subjects) and their non-IDU HIV-1-seronegative steady partners]. Baseline and follow-up (every 3-4 months) data included a structured questionnaire and blood testing for HIV infection and CD4+ cell subsets.
                Demographic characteristics of the 30 steady sex partners were evaluated as follows: sex (22 women, eight men); age (mean, 32 years; range, 21-55 years) and race (African-American, 13; Hispanic, 13; other, 4). The average duration of relationship between index subject and partner at study entry was 7.5 years (range, 4 months to 19.4 years). At entry, 27 of the 30 partners reported no or intermittent use of condoms with the index subject during a typical 12-month period. Follow-up data (median follow-up, 298 days; range, 85-992 days) were available for 22 partners. Of these, 15 reported no or intermittent condom use. For a total study observation time of 23 person-years, there were no seroconversions. The upper 95% confidence interval for the observed seroconversion rate of 0% is 13%.
                These results suggest that the likelihood of heterosexual HIV-1 transmission from seropositive methadone-maintained IDU to their seronegative, non-IDU steady sex partners is low. The risk of human immunodeficiency virus (HIV) transmission was studied by interviewing and testing the serum of heterosexual contacts and casual family contacts of adults with transfusion-associated HIV infections. Two (8%) of 25 husbands and ten (18%) of 55 wives who had had sexual contact with infected spouses were seropositive for HIV. Compared with seronegative wives, the seropositive wives were older (median ages, 54 and 62 years; P = .08) and actually reported somewhat fewer sexual contacts with their infected husbands (means, 156 and 82; P greater than .1). There was no difference in the types of sexual contact or methods of contraception of the seropositive and seronegative spouses. There was no evidence of HIV transmission to the 63 other family members. Although most husbands and wives remained uninfected despite repeated sexual contact without protection, some acquired infection after only a few contacts. This is consistent with an as yet unexplained biologic variation in transmissibility or susceptibility. To study incidence and risk factors of heterosexually transmitted HIV infection, we followed a cohort of 343 seronegative women, stable, monogamous partners of infected men whose only risk of acquiring HIV was sexual exposure to the infected partner. Nineteen seroconversions occurred in 529.6 person years (py) of observation, yielding an incidence rate of 3.6 per 100 py. The incidence rate was 7.2 per 100 py among women who did not always use or never used condoms and 1.1 among those who always used them [relative risk (RR) 6.6, 95% confidence interval (CI) 1.9-21.9]. Anal sex was associated with a risk increase in only those women not always using condoms (RR 1.4, 95% CI 0.4-4.8). No seroconversions were observed among 22 women using oral contraceptives. One of the women using intrauterine devices seroconverted. In couples who did not always use condoms, seroconversions occurred more frequently in partners of men with symptomatic diseases, with a low CD4+ cell number (< 400 per mm3) or with a detectable p24 antigen. In couples not always using condoms and where the man had a low CD4+ cell count, the joint presence of blood viral antigens and AIDS symptoms conditioned a fivefold increased risk of seroconversion of the woman (RR 5.4, CI 1.4-20.3). At multivariate analysis, women with longer relationships (> or = 1 year) showed a lower risk of seroconversion (RR 0.3, CI 0.1-0.8), and those partners of men positive for p24 antigen in serum had an increased risk of seroconversion (RR = 4.0, CI 0.1-0.8). Despite the importance of human immunodeficiency virus (HIV) transmission through heterosexual contact, the incidence of HIV infection in heterosexual cohorts has not been well studied, particularly in the developing world.
                To 1) determine the incidence of HIV infection in discordant heterosexual couples (couples in which one partner had HIV infection and the other did not) in Haiti and 2) assess risk factors for and methods of preventing HIV infection.
                Prospective study.
                National Institute for Laboratory Research, Portau-Prince, Haiti.
                475 HIV-infected patients and their noninfected regular sex partners.
                Patients and their partners were evaluated at 3- to 6-month intervals for HIV infection, sexually transmitted diseases, and sexual practices. The efficacy of counseling and provision of free condoms was also evaluated.
                Among the 177 couples who remained sexually active during the prospective study period, 20 seroconversions to HIV positivity occurred, for an incidence rate of 5.4 per 100 person-years (95% CI, 5.16 to 5.64 per 100 person-years). Thirty-eight couples (21.5%) discontinued sexual activity during the study. Only 1 seroconversion occurred among the 42 sexually active couples (23.7% of the 177 sexually active couples) who always used condoms. In contrast, the incidence in sexually active couples who infrequently used or did not use condoms was 6.8 per 100 person-years (CI, 6.49 to 7.14 per 100 person-years). Transmission of HIV was associated with genital ulcer disease, syphilis, and vaginal or penile discharge in the HIV-negative partner and with syphilis in the HIV-infected partner.
                Counseling and the provision of free condoms contributed to the institution of safe sex practices or abstinence in 45% of discordant heterosexual couples. However, 55% of couples reported that they continued to have unprotected sex, resulting in an incidence of HIV infection of 6.8 per 100 person-years. Forty-five adults with the acquired immunodeficiency syndrome (AIDS) and their 45 spouses, 109 children, and 29 household contacts were studied for evidence of heterosexual, perinatal, and household spread of human T-cell lymphotropic virus type III (HTLV-III) infection. Of the 45 spouses enrolled, 26 (58%) had antibody to HTLV-III, including 12 (71%) of 17 male spouses and 14 (50%) of 28 female spouses. Of the 12 seropositive male spouses, nine were seropositive at enrollment and three had seroconversion. Of the 14 seropositive female spouses, four were seropositive at enrollment and ten seroconverted. Lack of barrier contraceptive use and oral sex were associated with seroconversion. Of the 109 children enrolled, 15 had AIDS or an AIDS-related illness, two had evidence of passive transfer of maternal antibodies, and two had HTLV-III infection acquired outside the household. None of the 90 seronegative children seroconverted. Of 29 household contacts studied, none developed antibody to HTLV-III. To determine the incidence of heterosexual human immunodeficiency virus type 1 disease transmission and the effect of zidovudine therapy on this risk of transmission.
                A cohort of 436 monogamous seronegative female sexual partners of human immunodeficiency virus type 1-infected males was followed up for 740 person-years with regular structured interviews and laboratory tests.
                At enrollment of the women, 50% of their infected partners had one or more signs of disease progression (symptoms of acquired immunodeficiency syndrome, p24 antigen positivity, or CD4+ cell counts lower than 0.4 x 10(9)/L) and 15% were treated with zidovudine.
                Incidence rates of seroconversion were calculated and relative risks were estimated as incidence rate ratios.
                Twenty-seven women seroconverted during follow-up, and the incidence of seroconversion was 3.7 per 100 person-years. Seroconversion was about six times more frequent (relative risk, 5.8; 95% confidence interval, 2.2 to 15.3) in couples not using condoms. Men with signs of disease progression transmitted infection to their partners more frequently and were more frequently treated with zidovudine. When the risk of transmission was estimated accounting for disease progression, the rate of transmission in zidovudine-treated men was lower than in untreated men (relative risk, 0.5; 95% confidence interval, 0.1 to 0.9).
                Treatment of human immunodeficiency virus type-1 infected men with zidovudine reduces, but does not eliminate, heterosexual transmission of infection. Behavioral counseling that encourages sexual practices with a lower risk of transmission remains the most important method of prevention. Using lookback procedures and other methods, we identified and then prospectively followed human immunodeficiency virus type 1 (HIV-1)-infected transfusion recipients and their sex partners to determine AIDS incidence and risks of heterosexual transmission of HIV-1. At enrollment, 7 of 32 (21.9%) female partners of male recipients were themselves infected with HIV-1, as compared with none of 14 male partners of female recipients (p = 0.08). No additional episodes of transmission were observed. The prevalence of advanced immunodeficiency at enrollment was similar in male and female recipients. Male recipients with advanced immunodeficiency (CD4+ lymphocyte count < or = 0.20 x 10(9)/L or a history of clinical AIDS) at enrollment were more likely to have infected their female partners (odds ratio = 7.9; p = 0.03) than men with neither condition. Similarly, AIDS-free survival, as estimated by the product-limit method, was lower among male transmitters than among male nontransmitters (p = 0.01). Transmission was not associated with frequency of unprotected vaginal intercourse. Our data suggest that HIV-1-infected men who develop immunodeficiency rapidly are more likely to infect their sex partners and that the greater efficiency of male-to-female HIV-1 transmission is not explained by a greater number of sexual contacts or more advanced immunodeficiency in index subjects. Worldwide, the predominant mode of human immunodeficiency virus (HIV) transmission is heterosexual intercourse, but the risk of heterosexual transmission and the effectiveness of measures to prevent it are not well defined.
                We conducted a prospective study of HIV-negative subjects whose only risk of HIV infection was a stable heterosexual relationship with an HIV-infected partner. Every six months the subjects were interviewed, tested for HIV, and counseled about safe sexual practices.
                A total of 304 HIV-negative subjects (196 women and 108 men) were followed for an average of 20 months. During the study, 130 couples (42.8 percent) ended their sexual relationships, most often because of the HIV-infected partner's illness or death. Of the 256 couples who continued to have sexual relations for more than three months after enrollment in the study, only 124 (48.4 percent) used condoms consistently for vaginal and anal intercourse. Among these couples, none of the seronegative partners became infected with HIV, despite a total of about 15,000 episodes of intercourse. Among the 121 couples who used condoms inconsistently, the rate of seroconversion was 4.8 per 100 person-years (95 percent confidence interval, 2.5 to 8.4). Eleven couples refused to answer questions about condom use. The risk of transmission increased with advanced stages of HIV infection in the index partners (P < 0.02) and with genital infection in the HIV-negative partners (P < 0.04). Withdrawal to avoid ejaculation in the vagina had a protective effect in uninfected women (P < 0.02).
                Consistent use of condoms for heterosexual intercourse is highly effective in preventing the transmission of HIV. Among couples not using condoms regularly, the risk of HIV transmission varies widely. To determine whether HIV testing and counselling increased condom use and decreased heterosexual transmission of HIV in discordant couples.
                Prospective study.
                Kigali, the capital of Rwanda.
                Cohabiting couples with discordant HIV serology results.
                Condom use in the couple and HIV seroconversion in the negative partners.
                60 HIV discordant couples were identified, of whom 53 were followed for an average of 2.2 years. The proportion of discordant couples using condoms increased from 4% to 57% after one year of follow up. During follow up two of the 23 HIV negative men and six of the 30 HIV negative women seroconverted (seroconversion rates of 4 and 9 per 100 person years). The rate among women was less than half that estimated for similar women in discordant couples whose partners had not been serotested. Condom use was less common among those who seroconverted (100% v 5%, p = 0.01 in men; 67% v 25%, p = 0.14 in women).
                Roughly one in seven cohabiting couples in Kigali have discordant HIV serological results. Confidential HIV serotesting with counselling caused a large increase in condom use and was associated with a lower rate of new HIV infections. HIV testing is a promising intervention for preventing the spread of HIV in African cities. AIDS cases attributable to heterosexual vaginal intercourse constitute a growing proportion of new AIDS cases in the United States. Major cofactors that possibly increase the efficiency of heterosexual transmission of HIV-1 include genital ulcer disease, multiple sexual exposures, lack of male circumcision, and primary and advanced stages of HIV-1 disease. I report the case of a 33-year-old woman who was recently infected with HIV-1 after one to three nontraumatic episodes of vaginal intercourse with a healthy-appearing, HIV-1-infected, bisexual man. An investigation of her exposure history revealed the precise time frame during which infection occurred. The patient developed a primary HIV-1-infection syndrome and became seropositive for HIV-1 within eight weeks of her last sexual contact with the infected man. An epidemiological and laboratory evaluation of the index patient and her sexual partner identified only one risk factor for enhanced HIV-1 transmission: the patient's use of oral contraceptives. Her partner was immunologically intact, HIV-1 antigen negative, and circumcised. Both of the individuals were from Minnesota, as were their recent sexual partners. This case illustrates that HIV-1 infection by vaginal intercourse can occur in the absence of the major risk factors believed to increase the efficiency of transmission. Even in a low HIV-1 prevalence area like Minnesota, efforts to promote awareness of HIV-1 status, abstinence, non-penetrative sex, or barrier protection need to be expanded and the behaviors adopted by sexually active persons if HIV-1 transmission is to be minimized.
This review indicates that consistent use of condoms results in 80% reduction in HIV incidence. Consistent use is defined as using a condom for all acts of penetrative vaginal intercourse. Because the studies used in this review did not report on the "correctness" of use, namely whether condoms were used correctly and perfectly for each and every act of intercourse, effectiveness and not efficacy is estimated. Also, this estimate refers in general to the male condom and not specifically to the latex condom, since studies also tended not to specify the type of condom that was used. Thus, condom effectiveness is similar to, although lower than, that for contraception.