PEPFAR activities focus on expanding access to HIV prevention, treatment and care interventions. These include provision of antiretroviral treatment, pre-exposure prophylaxis (PrEP), voluntary male circumcision, condoms and other commodities related to HIV services. In addition, PEPFAR has launched specific initiatives in key strategic areas. For example, in 2015, PEPFAR launched DREAMS, a public-private partnership that aims to reduce HIV infections in adolescent girls and young women.
Before oral contraceptives became widely available, condoms were the preferred method of birth control among millions of U.S. teenagers. With the advent of the pill and the feminization of adolescent sexuality in the 1970s, condom use declined substantially. Despite a modest resurgence in condom use in the late 1970s (perhaps in response to publicity about the health dangers of the pill), the rate of condom use among teenagers leveled off in the 1980s. One recent estimate is that one-fifth of sexually active teenage girls who practiced contraception had partners who used condoms at last intercourse.
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Despite these drawbacks, it is well recognized that condoms have considerable virtues as a contraceptive method among teenagers. They are cheap, can be made readily available to adolescents, and can be used by teenagers without informing "establishment" figures such as physicians and parents. If used properly, condoms are quite effective at preventing both pregnancy and venereal disease. Condoms are perhaps the most effective contraceptive method during a couple's initial several encounters, before the girl elects a prescription method of contraception. In many adolescent relationships, women remain sexually active for more than a year before pursuing a prescription method.
The emergence of the AIDS epidemic is causing a serious reappraisal of the benefits and costs of increasing condom use among adolescents. Although the AIDS virus has so far penetrated only modestly beyond the traditional "high-risk" groups, there are reasons to target U.S. teenagers in the development of prevention activities. Adolescent life-style in the United States is characterized by sexual experimentation, multiple partners, frequent sexual intercourse, exposure to sexually transmitted diseases, and significant amounts of intravenous drug use. In light of all of the above, the potential role of condom use as an AIDS prevention strategy among teenagers needs to be analyzed.
A complete cost-benefit analysis of condom promotion and distribution programs is not attempted in this paper. Instead, some mathematical models are presented that are useful in simulating the potential HIV prevention benefits of increased condom use to the adolescent. The purpose is not to produce precise estimates of an adolescent's absolute risk of HIV infection, but rather to determine how much condom use might reduce an adolescent's risk of infection. These analyses also highlight what the data requirements of a comprehensive benefit analysis of condom use might be. Because the economic facets of AIDS prevention have already been examined in the previous example (premarital screening), the focus here is on the interrelationships among patterns of sexual behavior, extent of condom use, and rates of HIV infection.
If the uninfected teenager draws his or her partner randomly from the pool of U.S. adolescents and p is the prevalence of HIV infection among adolescents, the cumulative risk of infection then becomes
The corresponding hypothetical values of P are reported in Table 1. Note that hypothetical values have been used for the inputs because none of the true values for the U.S. teenage population is currently known with precision. The assumptions about teenage sexual behavior are roughly compatible with data reported in the 1987 National Academy of Sciences' report on adolescent sexuality and childbearing (Hayes, 1987; Hofferth and Hayes, 1987).
It is reasonable to expect the relative effectiveness of condoms against HIV infection to be greater among heterosexual adolescents than among homosexuals. Heterosexual adolescents draw partners from a population with relatively low rates of HIV prevalence compared to homosexuals. Moreover, homosexuals tend to practice sex more often and with more partners than heterosexual adolescents do. There is also reason to believe that anal intercourse is a more potent way to transmit the virus than vaginal intercourse. All of these factors help explain why the relative effectiveness of condom use (if not the absolute effectiveness) is larger among heterosexual adolescents than among homosexuals.
Results of the sensitivity analysis are reported in Table 2. As expected, the absolute risk of infection is influenced significantly by the new values of p and e. However, the relative effectiveness of the condom remains quite significant. At p = 0.015 and e = 0.5, half-time and full-time condom use cut the cumulative risk of infection by 18-25 and 40-50 percent, respectively, depending on the sexual activity assumptions. If e = 0.9 and p = 0.2, half-time and full-time condom use cut the risk by 40-50 and 86-90 percent, respectively, again depending upon the sexual activity assumptions. Because it is unlikely that any adolescent population is currently at p = 0.2 and it is likely that , condom use appears to be a promising strategy for reducing the risk of HIV infection among adolescents.
Suppose, for example, that 50 percent of adolescent sexual exposures are protected by condoms (f = 0.5). Although this could occur if all teens used condoms half the time, it could also result from half the teens using condoms all the time and the other half never using condoms.
The quantitative implications of this complication have been explored for the case in which 50 percent of adolescent exposures are protected by condoms (f = 0.5). It was assumed that either half of teens were full-time condom users and half nonusers or, alternatively, that all teens were half-time users. An attempt was made to determine which pattern of condom use would be most effective in preventing HIV infection.
that each member selects partners from one of several prevalence pools, in which the prevalence of HIV is pj. To simplify, let there be three pools with prevalence rates p1,p2, and p3. The probability that an at-risk adolescent draws from pool j is vj. Let the constraint be that:
In previous calculations, it was assumed in effect that p1 = p2 = p3 = p = 0.015. Suppose instead that there is a small population of adolescents (v1 = 0.02) with high HIV prevalence (p1 = 0.5), a large population (v2 = 0.48) with low prevalence (p2 = 0.01), and another large population (v3 = 0.50) with zero prevalence (p3 = 0). The relative effectiveness of condom use under these circumstances must then be determined.
It is easy to visualize this phenomenon by considering the case in which the adolescent at risk has a "superinfectious" partner. Even if the person at risk is protected by full-time condom use, the cumulative probability of infection increases rapidly as the number of exposures increases. Although the condom may be 90 percent effective per exposure, repeated exposures will ultimately infect the person at risk due to condom failure. The cumulative risk of infection is 0.65 from 10 "protected" exposures, 0.93 from 25 exposures, 0.995 from 50 exposures, and 0.99997 from 100 exposures. In a potential population of partners that is known to include such superinfectors, the choice of partner is far more critical to risk reduction than is condom use.
Even if superinfectors are in the pool of potential partners, condom use is somewhat effective if the number of exposures per partner is small. Because many adolescent sexual relationships involve only several (or even one or two) exposures, condom use is still an effective protection strategy. Hence, even an extreme case of heterogeneity in transmissibility ("superinfectors") does not eliminate the promise of condom use as a method to prevent HIV infection.
In all societies one of the major axes on which sexual life is ordered is the age of individuals as organized into a socially constructed life course (Clausen, 1972; Reigel and Meachum, 1976). However, the timing in the life course in which various forms of sexual conduct will be learned, expressed, and disappear, and the relationship of sexual conduct to other aspects of social and psychological life vary from one society to another and from one period to another in the history of any specific society (Ford and Beach, 1951; Marshall and Suggs, 1971; Dover, 1978; Katz, 1983; Herdt, 1984; Duberman, 1986; D'Emilio and Freedman, 1988). Thus not only does the patterning of sexuality even across such a relatively narrow life stage as adolescence differ in an advanced industrial society with a predominantly Judeo-Christian religious tradition like the United States and in developing societies with differing religious traditions, but also important differences can be found in the sexual lives of adolescents in the United States and those in other Western industrial societies (Jones et al., 1986). Similarly, differences in the sexual life of adolescents can be found across relatively short time spans in the history of the United States; one need only contrast the 1920s with the 1950s or either of these decades with the 1980s.
Infancy stretches in time from birth to the middle of the third year of life when independent locomotion and language skills have been developed. The center of the child's life moves from the mother (and less often a father or other caretaker) to a more extended group of individuals in and out of the family. Although, historically, the psychoanalytic tradition viewed these years as critical for mature psychosexual development, more contemporary research suggests that the importance of these early experiences (e.g., weaning, toilet training, parental attachment) to adolescent and adult sexual patterns is quite limited. This is in accordance with other work in human development which suggests that early experience may be less critical for later development than previously assumed, although this remains a serious point of controversy among developmental psychologists (Kagan, 1971). Perhaps of most importance in the United States is the successful acquisition of some elements of a conventionalized gender identity, and perhaps the most important of these is the preliminary sense of being a boy or a girl. Although it has been argued that this acquisition of gender identity is an all or none process somewhat like imprinting, a more cautious formulation would be that the components of the conventional gender identity package are probably learned in a more cumulative fashion over the entire period of childhood (Luria, 1979). 2ff7e9595c
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