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The Internet has been identified as a risk environment for STDs, including HIV, for several years. Like the HIV epidemic itself, this online risk environment rapidly increased in importance, and revealed critical areas of the public health infrastructure that require new expertise and support. In the first section of this chapter, we will discuss the risk environment of the Internet, with most of the focus on men who have sex with men (MSM). The second half of the chapter will focus on the potential of the Internet for facilitating STD/HIV prevention, health education, outbreak awareness, and other public health interventions. In times of rapid change, public health officials often learn by trial and error in the interest of expediency, rather than taking the time to establish careful, scientific evaluations of new interventions. Such is the case with the Internet; thus, while we describe many Internet-based interventions here, we have very little data to support the feasibility, acceptability, efficacy, cost-effectiveness, and generalizability of these efforts.

Approximately 19 million cases of sexually transmitted infections (STIs), occur in the United States each year (1). For sexually active persons, male latex condoms remain the most widely available and commonly used barrier method for prevention of STI (2). When used consistently and correctly, male condoms reduce the risk of pregnancy and most STIs, including HIV, according to results of laboratory and clinical studies. Levels of condom use have continued to increase in recent years, as shown in national surveys of adolescents and adults (3–6), largely in response to the HIV epidemic. Condom use at last intercourse, for example, has now risen to more than 60% among adolescents (4) and adults at risk (6). Moreover, according to the 2002 National Survey of Family Growth (NSFG) (3), more than 13 million reproductive age women currently use condoms for contraception or protection from STIs, an increase from 9 million in the 1995 survey (7). Condom use thus continues to be an important part of public health efforts to prevent acquisition of STIs.

While there is general consensus that condoms must play a central role in any STI/HIV prevention program (8), how strongly condoms should be recommended to sexually active persons and those contemplating sexual activity remains controversial. Despite recent increases in condom use, current levels of use are likely insufficient for effective prevention of STIs. Questions about the effectiveness of condoms for STI prevention have also raised concerns regarding public health recommendations for their use (9–11).

Primary prevention efforts for sexually transmitted infections (STIs) have historically focused on behavioral strategies, including encouraging abstinence, the delay of sexual initiation, careful partner selection, condom use, and partner management. Several potential emerging technologies, including microbicides and prophylactic vaccines, could add an additional focus to efforts to change individual sexual risk, at least in the case of certain STIs (1). One of the difficulties associated with traditional behavioral primary prevention efforts is that they seek to modify contextually complex, socially imbedded behaviors, such as condom use. The requirement for sustained behavior change over time adds to the difficulty of achieving long-term success with these kinds of interventions. In contrast, vaccination typically involves no more than three discrete events, which may be amenable to brief targeted interventions. The contextual complexity of vaccination is substantially less than with condom use, and effective vaccines would have no requirement for sustained behavior change. Efforts to encourage vaccination may need to differentially target specific immunization behaviors, including original and follow-up dosages, and possible booster shots.

Although getting vaccinated against an STI is, in many ways, a simpler behavior than consistent use of condoms in a sexual relationship, vaccination certainly will be uniquely challenging, requiring different approaches than those used to encourage safer sexual behaviors. It has been suggested that to have maximal impact, STI vaccination should occur prior to initiation of sexual activity, which often occurs during young adulthood (1–4). This suggestion to vaccinate adolescents is based on several considerations, including vaccine safety and efficacy studies among adolescents, data on STI epidemiology and age of sexual initiation in the United States, cost effectiveness evaluations, and established and recommended adolescent health care visits. Based on such considerations, the Advisory Committee on Immunization Practices(ACIP) unanimously voted in June 2006 to recommend a newly licensed HPV vaccine for routine delivery to females 11–12 years of age and for females 13–26 years of age who have not previously been vaccinated.

For the last several decades, public health professionals have increasingly recognized that the burden of sexually transmitted infections (STIs) is disproportionately high among adolescents and young adults. , the 1997 seminal report of the Institute of Medicine, clearly identified adolescents as a population at high risk for STIs (1). There has been a concerted effort to track rates of STI in this population, investigate its causes, and develop interventions to reduce risk and associated disease. In this chapter, we will define the burden of STI among youth, review behavioral and biological risk for STI, and discuss the current literature on effective adolescent risk reduction interventions.

We will take an ecological or social context approach that acknowledges the impact of social environmental factors on health and, therefore, intervention strategy (2). By social context, we mean the important people (e.g., peers, parents), places (e.g., neighborhoods), institutions (e.g., schools, health care organizations), and societal processes (e.g., culture, policy) that can influence adolescent behavior and health. As a period of biologic, cognitive, and psychosocial transitions, adolescence may be more sensitive to contextual influences than other periods. Biologic, cognitive, and social changes during adolescence can affect behaviors and relationships and require guidance from important others and institutions that may not be prepared for their roles. For example, peers share information that may not be correct, parents may not recognize adolescent risk behavior, and schools may be too politically or financially challenged to provide effective prevention programming. In our review, we will identify the social context influences on adolescent risk for STIs and intervention strategies designed to address those influences.

Women are disproportionately affected by the burden and consequences of STDs, including human immunodeficiency virus (HIV). Of the estimated 19 million cases of STDs that occur annually in the United States (1), about two-thirds are in women (2). Further, both bacterial and viral STDs are associated with negative sequelae in women. Untreated gonococcal and chlamydial infections can produce significant and disproportionate reproductive system morbidity in women, including pelvic inflammatory disease, infertility, ectopic pregnancy, and chronic pelvic pain (2,3). Additionally, about 70% of chlamydia infections and 50% of gonococcal infections are asymptomatic in women, causing a delay in seeking care and an increase in the risk for negative sequelae (3,4).

Genital human papillomavirus (HPV) infection, the most common sexually transmitted viral infection worldwide, can also produce negative sequelae for women. Although most genital HPV infections are transient (i.e., are cleared by a healthy immune system), persistent infection with oncogenic or high-risk types are associated with cervical abnormalities and cervical cancer, while infection with other types can produce genital warts (5). Further, infection with herpes simplex virus, also common in women, can produce painful outbreaks, and in pregnant women, can result in perinatal transmission and serous neonatal infection (3).

Men who have sex with men (MSM) have assumed particular importance in the epidemiology of STDs in many western industrialized countries (1,2). In part, this is driven by the higher prevalence of sexual risk behaviors within this population subgroup and the consequent increased probability of STD transmission and acquisition. Other factors, for example, patterns and distribution of sexual networks, background disease prevalence, and the effectiveness of targeted prevention interventions, also contribute to the observed and evolving epidemiology. In this chapter, we overview the recent increases in reported STDs among MSM in the United States, explore the behavioral and psy-chosocial determinants of STD transmission, and consider the evidence regarding effective STD and HIV behavioral interventions for improving sexual health outcomes within this group.

A wide-ranging set of search strategies was used in an attempt to identify as many types of recent data sources relevant to the subject. The topic search was developed using a combination of specific STD prevention terms, terms for interventions specific to the topic area, and general health promotion/health education/public health terms combined with topic terms such as STD or sexual behavior, and limited to the United States. MEDLINE, EMBASE, PsycINFO, Sociofile, and CINAHL databases were searched from January 1999 to October 2005 for references published in the English language. The search strategies were as similar as possible for the different databases, however, index terms differed across some databases. Review of the published literature was supplemented with data obtained from relevant STD surveillance and prevention reports. Attempts were made to obtain all papers, including journal articles, reports and book chapters, with prioritization of review articles.

STD repeaters are important as a population of study for two primary reasons: 1) repeat infections may lead to an increased risk in STD sequelae, and 2) persons with repeat infections represent a disproportionate share of STD morbidity and may be members of the core group or core transmitters. We argue that it is likely that there are two different groups of repeaters. First, there are women who are the recipients of repeat infection as a result of the risky behaviors of their sex partners. Second, there are heterosexual and homosexual men and some women who engage in behavior that is more typical of core transmission patterns. These groups will require different interventions. We discuss these issues further later in the chapter.

It is worth delineating what we mean when we talk about “STD repeaters” or “repeat infections with STDs.” Generally, when used in the research literature, “repeaters” are individuals who acquire more than one nonviral STD infection in a specified period of time. Some studies focus solely on repeat episodes of gonorrhea (1–6); some focus exclusively on two or more infections with chlamydia (7–11). Other studies consider several different STDs when defining repeaters (12–15). What appears to be most important is that, regardless of specific disease, repeaters are an important population and are at an increased risk for STD acquisition and sequelae. Furthermore, some repeaters may be largely responsible for maintaining core transmission groups that spread disease throughout the community.

In the United States, there are approximately 2.2 million adults housed in correctional facilities (1). Approximately 6.9 million, or 3.2% of the U.S. population, are under some form of correctional supervision (i.e., prison, jail, on probation or parole) (2,3). The number of U.S. citizens incarcerated has continued to increase since 1980. The number of U.S. inmates in prisons, jails, and on parole has more than tripled (2–4). The number of U.S. persons on probation has more than quadrupled from 1,118,097 in 1980 to over 4.1 million in 2004 (4). Many states are now spending almost as much money on building correctional institutions as is spent on building and maintaining institutions of learning (5–7), which has had its most profound effect on educational achievement among ethnic minorities and those with lower socioeconomic backgrounds (8).

Increased populations are disproportionately undereducated and minority. Over two-thirds (68%) of state prison inmates did not receive a high school diploma (9). Black and Hispanic males have a 1 in 4 and 1 in 6, respectively, lifetime chance of being incarcerated, which is considerably higher than white males, who have a 1 in 23 chance (10). Incarcerated individuals and those with incarceration histories are disproportionately affected by substance use and abuse, have higher rates of behavioral risk, and high prevalence of health challenges (11). The considerable prevalence of STDs/HIV in communities co-affected by high rates of incarceration (and the associated factors) is indicative of a failed societal effort to devise healthy communities and inhibit criminogenic motivations, as well as a failed public health effort to facilitate health care access and acquisition of optimal health.

The magnitude of STDs other than HIV in drug users who engage in heterosexual behaviors has not been well assessed in the scientific literature. Similarly, the profile of effective STD risk-reduction interventions for drug users is limited because few interventions have been developed beyond HIV prevention to reduce the risk for the sexual transmission of bacterial and viral STDs in this population. The lack of data on STDs in drug users and on relevant interventions is in marked contrast to the extensive literature on hepatitis B and C(1–4) and HIV (5–8) in drug users.

We aim in this chapter to review and summarize the literature on STDs (excluding HIV) in drug users who engage in heterosexual behaviors and to describe the existing profile of STD-related prevention and control activities specific to drug users. We review three bacterial STDs—syphilis, gonorrhea, and chlamydia—and two viral STDs—hepatitis B and genital herpes. We focus primarily on the scientific studies conducted with heterosexual drug users in the United States, that were published between 1995 and early 2005. Although control of infection with human papilloma virus (HPV) is important for control of cervical cancer, it is worthwhile noting that only two studies were found that mentioned HPV among drug users (9,10), despite the imminent and recent availability of a vaccine for HPV.

In order to ascertain whether any behavior needs intervention, the form that intervention should take, or whether an intervention is effective, careful attention must be paid to measurement. Measurement exists in many forms throughout public health, ranging from clinical applications to monitoring, surveillance, and intervention efforts. We count the number of infected individuals, measure the effective dose of medications, and measure a variety of physical characteristics of our patients. Measuring behavior, however, is a complicated business, requiring careful forethought regarding the exact information we want to gather. In most cases, we will be unable to directly observe the behaviors that put people at risk—or reduce their risk—for STDs. Thus, we must rely on questionnaires, interviews, role-play scenarios, biological outcomes, and other forms of measurement to assess a person's risk for STD. Each type of measurement can provide important contributions to the knowledge of behavioral risk for STD. Ideally, the information obtained from the various measurement methods will converge to provide a coherent picture of the behaviors that lead to disease transmission, and how to intervene upon them.

In this chapter, we will address several different forms of measurement that can provide useful information in the context of a behavioral intervention. In addition, we will discuss the methods by which researchers can determine whether their measurements, whatever their type, are “accurate.” That is, we will discuss the extent to which different measurements can adequately represent the true nature of the behaviors we measure. In the literature related to self-reported behaviors, the term is rarely used, but instead we focus on evaluating the and of instruments. These terms are used to refer to the quality of a number of different kinds of measurement in public health.