Impact of highly active antiretroviral treatment on HIV seroincidence among men who have sex with men: San Francisco

Sustaining safe practice: twenty years on

This paper examines the ways in which populations at risk of HIV in the developed world have enculturated the knowledges and technologies of both the medical and the social sciences. By revisiting a number of review papers and by reviewing findings from a range of studies, we argue that gay men have appropriated information that has enabled them to sustain safe practices while they have eschewed information that has made maintenance difficult. The paper describes a range of risk reduction strategies and compares the responses of populations at risk of HIV in the years before the advent of highly active antiviral therapy (HAART) with their responses after the introduction of HAART in 1996. We concentrate our argument on the changing responses to HIV risk of gay men, although occasionally illustrate our argument with reference to the responses of injecting drug users. The responses of gay men to risk post-HAART--particularly those who reside in Australia--speak to the adoption of a range of considered strategies, not altogether safe, to reduce harm. We argue that such strategies need to be understood and addressed within a 'new' social public health, that is, a public health that takes what social analysis has to say seriously. The paper examines the differences between the traditional, the 'modern' epidemiological/clinical and the 'new' social or socio-cultural public healths and describes the tensions between the medical and the social science disciplines in their efforts to inform public health. Key concepts provided by social science such as agency (including individual and collective agency), alongside its methodological reflexivity are key to effective public health. The risk avoidance strategies adopted by gay men suggest a way forward by turning our attention to the ways in which medicine is taken in(to) their practice.

Unprotected anal intercourse between potentially HIV-serodiscordant men who have sex with men, San Francisco

BACKGROUND

Increasing trends in high-risk sexual behavior are noted among men who have sex with men (MSM) worldwide. Less information is available on unprotected sex between persons of different HIV serostatus.

METHODS

From 1999 through 2001, volunteers of a community-based organization conducted interviews of 10,579 MSM at gay-oriented venues in San Francisco and in neighborhoods with high-volume MSM pedestrian traffic. The questionnaire recorded demographic and risk behavior information, including self-reported and partners' HIV serostatus.

RESULTS

Potentially serodiscordant unprotected anal intercourse (UAI) with at least 2 anal sex partners was reported by 12.7% and increased from 11.0% in 1999 to 16.2% in 2001. Stratifying by self-reported HIV serostatus, 20.8% of HIV-positive respondents, 12.1% of HIV-negative respondents, and 13.4% of MSM who did not know or report their own HIV serostatus had potentially serodiscordant UAI. Older MSM of white race were more likely to report potentially serodiscordant UAI among HIV-positive respondents, whereas younger MSM of white race were more likely to report potentially serodiscordant UAI among HIV-negative respondents. Among those with unknown HIV serostatus, MSM of color were more likely to engage in potentially serodiscordant UAI.

CONCLUSION

Recent increases in UAI among MSM in San Francisco are not only the result of increases in UAI between persons of the same HIV serostatus. Prevention messages must address disclosure of HIV serostatus to sexual partners specifically tailored to groups according to age, community, and HIV serostatus.

Economic implications of failure to reduce incident HIV infections by 50% by 2005 in the United States

BACKGROUND

The Centers for Disease Control and Prevention have set a national goal of reducing new HIV infections by 50% by 2005 in the United States. There are no available published estimates of the economic consequences of failure to meet this national goal, however.

OBJECTIVES

The purpose of this article is to calculate the potential net economic implications of a failure to meet the national HIV prevention goal of reducing new HIV infections by 50% by 2005.

METHODS

Standard methods of cost-effectiveness analysis were used to determine 1) the excess number of HIV infections incurred if the goal is not met and 2) the excess net medical costs (without the cost of an expanded HIV prevention program in the United States) incurred if the goal is not achieved.

RESULTS

Base case results indicate that if the goal is not met, 130,000 excess HIV infections will occur between the present and 2010 and that the excess net medical costs incurred will total over $18 billion during the same time frame. Sensitivity analyses indicate that although changes in some parameter values do alter the quantitative results, none alter the basic qualitative finding that even dramatically expanded HIV prevention efforts that reduce new HIV infections by 50% are actually cost saving to society.

CONCLUSIONS

The human and fiscal stakes of meeting the CDC's national HIV prevention goal of reducing new infections by 50% by 2005 are sufficiently large to make the achievement of this goal an urgent public health priority.

HIV infection and associated risks among young men who have sex with men in a Florida resort community

OBJECTIVE

Several recent studies have reported high rates of sexual risk-taking and HIV infection among young men who have sex with men (MSM). Most of these studies used samples of convenience. The authors obtained population-based data on young MSM living in South Beach (Miami Beach, Florida), a resort community where some of the highest AIDS rates in the United States have been reported.

METHODS

A household probability sample was drawn to survey unmarried 18- to 29-year-old MSM living in South Beach. Subjects were interviewed, completed self-administered questionnaires, and provided oral specimens for HIV antibody testing.

RESULTS

From the 2,622 screened residential units, 100 mostly white and Hispanic MSM (92.6% of eligible participants) were enrolled in the study. Fifteen percent of the sample tested positive for antibodies to HIV. White and Hispanic MSM had similar rates. Forty-five percent of the sample reported engaging in unprotected anal intercourse (UAI) in the prior 12 months, and 31% reported UAI with a nonprimary partner. The estimated annual incidence of HIV infection was 6.3%.

CONCLUSION

The high prevalences of UAI and HIV infection in South Beach attest to a previously undocumented public health concern. The extremely high estimated incidence for young MSM in South Beach highlights the urgent need for more effective risk-reduction interventions and further epidemiological research on resort areas.

High-risk behaviors among men who have sex with men in 6 US cities: baseline data from the EXPLORE Study

OBJECTIVES

We describe the prevalence of risk behaviors at baseline among men who have sex with men (MSM) who were enrolled in a randomized behavioral intervention trial conducted in 6 US cities.

METHODS

Data analyses involved MSM who were negative for HIV antibodies and who reported having engaged in anal sex with 1 or more partners in the previous year.

RESULTS

Among 4295 men, 48.0% and 54.9%, respectively, reported unprotected receptive and insertive anal sex in the previous 6 months. Unprotected sex was significantly more likely with 1 primary partner or multiple partners than with 1 nonprimary partner. Drug and alcohol use were significantly associated with unprotected anal sex.

CONCLUSIONS

Our findings support the continued need for effective intervention strategies for MSM that address relationship status, serostatus of partners, and drug and alcohol use.

Viagra use in a community-recruited sample of men who have sex with men, San Francisco

The authors conducted a community-based anonymous survey of 837 men who have sex with men (MSM) to gauge the extent of Viagra (sildenafil citrate) use, its association with high-risk sexual behavior, and its combination with other drugs. Participants' mean age was 35 years, 67% were white, and 66% had a college degree. The majority (76%) reported anal sex in the past 6 months, with 49% reporting always using condoms. Overall, 32% had ever used Viagra (CI: 29%-36%). Significant independent predictors of Viagra use were white race, older age, HIV positivity, illicit drug use, and having had unprotected anal sex with potentially serodiscordant partners. Over one third of Viagra users had combined Viagra with other drugs, 18% with amyl nitrate. Only a minority (44%) obtained Viagra under the care of a physician. For some MSM, Viagra appears to be an emerging contributing factor to unsafe sex, potentially increasing HIV transmission. HIV care and prevention providers should target Viagra users for enhanced education on safer sex and potentially harmful drug interactions.

AIDS mortality may have contributed to the decline in syphilis rates in the United States in the 1990s

BACKGROUND

The mortality associated with AIDS among men may have had an influence on primary and secondary syphilis trends among men in the United States, through the loss of men at high risk for acquisition or transmission of syphilis in this population and/or by prompting safer sexual behaviors in response to the threat of AIDS.

GOAL

The goal of this study was to examine the association between AIDS mortality rates and primary and secondary syphilis incidence rates among men in the United States from 1984 to 1997.

STUDY DESIGN

We used a fixed-effects regression analysis of state-level AIDS mortality rates and primary and secondary syphilis incidence rates for men.

RESULTS

Our analysis showed a significant association between higher AIDS mortality and lower rates of syphilis incidence, after we controlled for confounding factors. Our model estimates suggested that every 20 AIDS deaths per 100,000 adult men are associated with declines of about 7% to 12% in syphilis incidence rates among men.

CONCLUSION

Increases in AIDS-associated mortality may have accounted for one-third to one-half of the decline in syphilis rates among men in the early 1990s. Recent declines in AIDS mortality in the United States may have contributed to the recent outbreaks of syphilis, particularly among men who have sex with men. Our findings underscore the importance of providing STD prevention services to men with HIV infection and the need for STD surveillance in communities at risk for syphilis outbreaks.

Risk factors for incident HIV infection among anonymous HIV testing site clients in Santos, Brazil: 1996-1999

OBJECTIVES

To determine temporal trends in HIV infection and risk factors among persons seeking anonymous HIV testing in Santos, Brazil.

METHODS

Data and sera from persons testing for HIV from 1996 to 1999 were used. Exposures were abstracted from HIV testing risk assessments. Stored HIV-positive sera were tested to identify recently acquired HIV infection using a serologic testing algorithm for detecting recent HIV seroconversion (STARHS). Independent associations between exposures and recently acquired HIV infection were determined using multivariate analyses.

RESULTS

Overall, estimated HIV incidence was 2.0% (95% CI: 1.1-3.5) for the 4-year period: 1.2% (95% CI: 0.5-2.6) in women and 2.7% (95% CI: 1.3-5.0) in men. Incidence increased among women but remained stable among men. Exposures independently associated with incident infection included a history of sex work (OR= 5.4, 95% CI: 1.5-18.7), concurrent syphilis infection (OR =4.1, 95% CI: 1.4-11.9), anal sex (OR = 3.0, 95% CI: 1.3-7.1), and having an HIV-positive sexual partner (OR= 1.4, 95% CI: 1.1-1.9).

CONCLUSIONS

This study further demonstrates the public health utility of using the STARHS for the assessment of emerging trends in the HIV epidemic. Results from this study will help to target appropriate prevention strategies directed toward at-risk populations in Santos.

Sexually Transmitted Diseases in Men Who Have Sex with Men: An Epidemiologic Review

The introduction of highly active antiretroviral therapy (HAART) has led to dramatic reductions in morbidity and mortality due to HIV infection. However, the resulting optimism and improved health status produced by HAART appears to have contributed to unanticipated consequences in men who have sex with men (MSM): loss of fear of acquiring and transmitting HIV, an increase in high-risk sex, decreased use of condoms, and a resurgence of gonorrhea and syphilis. Other factors, such as lack of knowledge of sexually transmitted diseases (STDs), use of the Internet as a venue to find sex partners, the increasing use of Viagra (Pfizer, New York, NY) as a recreational drug, and the apparent expanding role of oral sex in STD transmission are fueling these trends. Since ulcerative and inflammatory STDs facilitate HIV transmission, a new wave of HIV infection in MSM may be on the horizon. The rising STD rates and relapses in high-risk sexual behaviors in MSM, both HIV-infected and -uninfected MSM, have profound implications for public health and the clinical management of these patients. Clinicians should be aware of this turn of events, and implement new screening and counseling guidelines that have been issued in response to these alarming reports.

Characteristics of individuals with male-to-male and heterosexually acquired infectious syphilis during an outbreak in Calgary, Alberta, Canada

BACKGROUND

Eliminating syphilis is important not only to prevent the sequelae of infection but also to control the spread of HIV. Current prevention and control efforts in Canada have been ineffective in eliminating this disease.

GOAL

The goal of the study was to determine the characteristics of individuals with infectious syphilis due to male-to-male and heterosexual contact, diagnosed during an outbreak in Calgary, Alberta, Canada.

STUDY DESIGN

This was a prospective study of individuals with infectious syphilis diagnosed at the STD clinic in Calgary between January 2000 and April 2002.

RESULTS

The outbreak reported here (September 2000 to April 2002) involves 32 cases of infectious syphilis, corresponding to rates of 0.9/100,000 population during 2000 and 1.8/100,000 population during 2001. Between September 2000 and June 2001, the cases diagnosed were among men who have sex with men (MSM); between May 2001 and April 2002, they were due to locally acquired infections among heterosexuals, including one case of congenital syphilis. Compared to the heterosexuals, MSM tended to be older, be coinfected with HIV, and report excessive alcohol use (versus injection drug use) and had infectious syphilis diagnosed earlier. MSM used the Internet and bars or bathhouses to initiate sexual contact, whereas heterosexually acquired infections were largely among sex workers and their clients. Contact tracing was more successful among the heterosexuals than among MSM. The public health staff at the STD clinic initiated a series of multifaceted interventions in response to the outbreak. These interventions were moderately successful, as measured by the increased numbers of individuals seeking counseling and testing services at the clinic.

CONCLUSION

The results highlight key differences in the risk factor-specific characteristics of the outbreak that should be taken into account when designing prevention and control strategies.

Key issues for a potential human immunodeficiency virus vaccine

A safe, effective, and affordable vaccine remains the best long-term hope for bringing the global human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic under control. Recent scientific developments have suggested that the first generation of HIV vaccines available for public health care use will likely be of low to moderate efficacy, compared with currently licensed vaccines for other diseases. Nevertheless, such "partially effective" HIV vaccines could provide considerable individual and public health benefits. A consultation was held in January 2002 to advise the Centers for Disease Control and Prevention (Atlanta, Georgia) about critical issues that need to be addressed in anticipation of the eventual licensure and availability of an HIV vaccine in the United States. The present article summarizes the major issues discussed at the consultation with regard to the potential use of a partially effective vaccine in HIV prevention programs in the United States and the activities that are needed to prepare for vaccine availability.

Sexually transmitted diseases and human immunodeficiency virus-discordant partnerships among men who have sex with men

Sexually active men who have sex with men (MSM) at 5 Seattle clinics were assessed for bacterial sexually transmitted diseases (STDs), human immunodeficiency virus (HIV)-discordant partnerships, sexual behavior, and drug use. Of the HIV-positive men, 45% reported having HIV-negative sex partners and 42% reported having sex partners with unknown serostatus during the past 2 months, whereas 14% and 57% of HIV-negative men reported having HIV-positive and unknown-serostatus sex partners, respectively. Correlates of sex partners with unknown serostatus were recruiting sex partners at bathhouses or parks. Gonorrhea, chlamydia, or syphilis was diagnosed in 12% of HIV-positive and 13% of HIV-negative MSM, and the rates did not differ between men with HIV-concordant and HIV-discordant partnerships. High prevalences of bacterial STDs and HIV-discordant partnerships emphasize the need for interventions to foster serostatus discussion, condom use, fewer anonymous partners, and STD screening.

Could widespread use of combination antiretroviral therapy eradicate HIV epidemics?

Current combination antiretroviral therapies (ARV) are widely used to treat HIV. However drug-resistant strains of HIV have quickly evolved, and the level of risky behaviour has increased in certain communities. Hence, currently the overall impact that ARV will have on HIV epidemics remains unclear. We have used a mathematical model to predict whether the current therapies: are reducing the severity of HIV epidemics, and could even lead to eradication of a high-prevalence (30%) epidemic. We quantified the epidemic-level impact of ARV on reducing epidemic severity by deriving the basic reproduction number (R(0)(ARV)). R(0)(ARV) specifies the average number of new infections that one HIV case generates during his lifetime when ARV is available and ARV-resistant strains can evolve and be transmitted; if R(0)(ARV) is less than one epidemic eradication is possible. We estimated for the HIV epidemic in the San Francisco gay community (using uncertainty analysis), the present day value of R(0)(ARV), and the probability of epidemic eradication. We assumed a high usage of ARV and three behavioural assumptions: that risky sex would (1) decrease, (2) remain stable, or (3) increase. Our estimated values of R(0)(ARV) (median and interquartile range [IQR]) were: 0.90 (0.85-0.96) if risky sex decreases, 1.0 (0.94-1.05) if risky sex remains stable, and 1.16 (1.05-1.28) if risky sex increases. R(0)(ARV) decreased as the fraction of cases receiving treatment increased. The probability of epidemic eradication is high (p=0.85) if risky sex decreases, moderate (p=0.5) if levels of risky sex remain stable, and low (p=0.13) if risky sex increases. We conclude that ARV can function as an effective HIV-prevention tool, even with high levels of drug resistance and risky sex. Furthermore, even a high-prevalence HIV epidemic could be eradicated using current ARV.

Sexual risk behaviors and implications for secondary HIV transmission during and after HIV seroconversion

OBJECTIVES

To determine the potential for secondary HIV transmission among newly HIV-infected men who have sex with men (MSM) during their HIV antibody seroconversion period, and for the 12 months after seroconversion.

DESIGN

A cohort study.

METHODS

Risk assessment questionnaires administered before receipt of the first positive HIV antibody result, plasma and seminal viral load measurements, and risk assessments one month and quarterly after receipt of the first HIV-positive test, and generalized estimating equation modelling techniques to analyse behavioral trends.

RESULTS

Of 66 seroconverters, more than half reported unprotected anal intercourse (UAI) with HIV-negative or unknown-serostatus partners during seroconversion, with 27% reporting insertive UAI with an HIV-negative partner. The initial median plasma viral load was 4.6 log/ml, the median seminal viral load was 2.7 log/ml, suggesting a high level of infectiousness. Compared with risk behavior during seroconversion, UAI with HIV-negative or unknown-serostatus partners was reduced after the receipt of positive antibody results; however, a substantial proportion of participants reported high-risk behaviors for transmission for 12 months of follow-up. After learning of their HIV infection, recent seroconverters did not reduce the risk of secondary transmission by engaging in proportionally more high-risk practices with HIV-infected partners (compared with HIV-negative or unknown-serostatus partners), or engaging in proportionally more receptive compared with insertive UAI.

CONCLUSION

Substantial potential exists for secondary HIV transmission during and for one year after HIV seroconversion. Receipt of an HIV-positive test is associated with a significant reduction in risk behavior, reinforcing the need to identify and counsel recently HIV-infected MSM.

Increased risk of HIV and sexually transmitted disease transmission among gay or bisexual men who use Viagra, San Francisco 2000-2001

The potential role of sildenafil (Viagra) in the risk of HIV and sexually transmitted disease (STD) transmission was evaluated among gay or bisexual men seeking public STD services in San Francisco. Viagra users reported greater numbers of recent sex partners, higher levels of unprotected anal sex with an HIV-positive partner, and higher rates of prevalent STD than non-users. Moreover, mixing Viagra with illicit drugs was commonly reported. Further studies are needed to determine whether a causal role exists.

[Recommendations of the Spanish AIDS Study Group (GESIDA) and the National Aids Plan (PNS) for antiretroviral treatment in adult patients with human immunodeficiency virus infection in 2002]

OBJECTIVE

To provide an update of recommendation on antiretroviral treatment (ART) in HIV-infected adults.Methods. These recommendations have been agreed by consensus by a committee of the spanish AIDS Study Group (GESIDA) and the National AIDS Plan. To do so, advances in the physiopathology of AIDS and the results on efficacy and safety in clinical trials, cohort and pharmacokinetics studies published in biomedical journals or presented at congresses in the last few years have been reviewed. Three levels of evidence have been defined according to the data source: randomized studies (level A), case-control or cohort studies (level B) and expert opinion (level C). Whether to recommend, consider, or not to recommend ART has been established for each situation.

RESULTS

Currently, ART with combinations of at least three drugs constitutes the treatment of choice in chronic HIV infection. In patients with symptomatic HIV infection, initiation of ART is recommended. In asymptomatic patients initiation of ART should be based on the CD41/mL lymphocyte count and on the plasma viral load (PVL): a) in patients with CD41 lymphocytes < 200 cells/mL, initiation of ART is recommended; b) in patients with CD41 lymphocytes between 200 and 300 cells/mL, initiation of ART should, in most cases, be recommended; however, it could be delayed when the CD41 lymphocyte count remains close to 350 cells/mL and the PVL is low, and c) in patients with CD41 lymphocytes > 350 cells/mL, initiation of ART can be delayed. The aim of ART is to achieve an undetectable PVL. Adherence to ART plays a role in the durability of the antiviral response. Because of the development of cross-resistance, the therapeutic options in treatment failure are limited. In these cases, genotypic analysis is useful. Toxicity limits ART. The criteria for ART in acute infection, pregnancy and postexposure prophylaxis and in the management of coinfection with HIV and hepatitis C and B virus are controversial.

CONCLUSIONS

The current approach to initiating ART is more conservative than in previous recommendations. In asymptomatic patients, the CD41 lymphocyte count is the most important reference factor for initiating ART. Because of the considerable number of drugs available, more sensitive monitoring methods (PVL) and the possibility of determining resistance, therapeutic strategies have become much more individualized.

Can antiretroviral therapy be used to prevent sexual transmission of human immunodeficiency virus type 1?

Approximately 5 million people annually are newly infected with human immunodeficiency virus (HIV). Although education, behavior modification, and promotion of condom use are effective transmission-prevention measures, the severity of the pandemic demands that all possible prevention strategies be explored. Antiretroviral therapy has the potential to decrease sexual transmission of HIV type 1 by reducing levels of HIV RNA and thus decreasing the risk that infected persons will transmit the disease or by its use as preexposure or postexposure prophylaxis. In this article, we explore the rationale for using antiretroviral therapy to prevent sexual transmission of HIV, as well as the limitations of this approach.