HIV is hyperendemic among men who have sex with men in San Francisco: 10-year trends in HIV incidence, HIV prevalence, sexually transmitted infections and sexual risk behaviour

OBJECTIVES

To evaluate trends in the HIV epidemic among men who have sex with men (MSM) in San Francisco and the implications for HIV prevention.

METHODS

An ecological approach assessed temporal trends in sexual risk behaviour, sexually transmitted infections (STI), HIV incidence and prevalence from multiple data sources between 1998 and 2007.

RESULTS

By 2007, there were over 13 000 HIV-infected MSM living in San Francisco. No consistent upward or downward temporal trends were found in HIV incidence, newly reported HIV cases, AIDS deaths, proportion of AIDS cases using antiretroviral therapy, rectal gonorrhoea or primary and secondary syphilis cases among MSM during the study period. Trends in indicators of sexual risk behaviour among MSM were mixed. Overall, unprotected anal intercourse (UAI) increased in community-based surveys. Among HIV-positive MSM, no significant trends were noted for UAI. Among HIV-negative MSM, UAI with unknown serostatus partners decreased but increased with potentially discordant serostatus partners. Among MSM seeking HIV testing, increases were noted in insertive UAI at anonymous testing sites and at the STI clinic, in receptive UAI at anonymous test sites and in receptive UAI with a known HIV-positive partner at the STI clinic.

CONCLUSIONS

Temporal trends in multiple biological and behavioural indicators over the past decade describe a hyperendemic state of HIV infection among MSM in San Francisco, whereby prevalence has stabilised at a very high level. In the absence of new, effective prevention strategies this state will persist.

The completeness, validity, and timeliness of AIDS surveillance data

PURPOSE

To assess the completeness, validity, and timeliness of the AIDS surveillance system after the 1993 change in the surveillance case definition.

METHODS

To assess completeness of AIDS case reporting, three study sites conducted a comparison of their AIDS surveillance registries with an independent source of information. To evaluate validity, the same sites conducted record reviews on a sample of reported AIDS cases, we then compared agreement between the original report and the record review for sex, race, and mode of transmission. To evaluate timeliness, we calculated the median delay from time of diagnosis to case report, before and after the change in case definition, in each of the three study sites.

RESULTS

After expansion of the case definition, completeness of AIDS case reporting in hospitals (> or = 93%) and outpatient settings (> or = 90%) was high. Agreement between the information provided on the original case report and the medical record was > 98% for sex, > 83% for each race/ethnicity group; and > 67% for each risk group. The median reporting delay after the change was four months, but varied by site from three to six months.

CONCLUSIONS

The completeness, validity, and timeliness of the AIDS surveillance system remains high after the 1993 change in the surveillance case definition. These findings might be useful for programs implementing integrated HIV and AIDS surveillance systems.

Undiagnosed and unreported AIDS deaths: results from the San Francisco Medical Examiner

To determine whether AIDS surveillance misses a substantial number of persons who die with unreported AIDS, we conducted a cross-sectional survey of decedents examined by the San Francisco (SF) Medical Examiner. Decedents who received toxicology screening were tested for HIV antibody and examined for evidence of AIDS. Names of decedents with positive or indeterminate HIV antibody test results were cross-referenced against the SF AIDS registry to identify previously reported AIDS cases. Medical records of unreported cases were reviewed to determine whether AIDS had been diagnosed prior to death. Of 1959 decedents tested, 176 (9%) were HIV positive; 105 (60%) were identified as having AIDS by the Medical Examiner. Of the 105 AIDS cases, 101 (96%) had been previously diagnosed; 98 (97%) had been previously reported. Overall, diagnosis and reporting were 93% complete. HIV-infected decedents were more likely than those uninfected to be men and <45 years old, and less likely to be Asian/Pacific Islander or Native American (p <.001). They were more likely to have died of suicide (p <.05) or drug abuse/overdose (p <.001). In SF, AIDS case reporting is highly complete. Current surveillance activities, which identify cases from health care settings, are appropriate. To decrease deaths among HIV-infected persons, suicide prevention and substance abuse treatment programs are needed.

Accuracy of self-reports of acquired immunodeficiency syndrome and acquired immunodeficiency syndrome-related conditions in women

To investigate the validity of self-reported acquired immunodeficiency syndrome (AIDS) among women enrolled in a prospective study of human immunodeficiency virus (HIV) infection, the authors compared the self-reported occurrence of AIDS-specific diagnoses with AIDS diagnoses documented by county AIDS surveillance registries. Also examined was the association between participant characteristics and the validity of self-reports. Among the 339 HIV-infected participants in the Northern California Women's Interagency HIV Study between October 1994 and September 1998, 217 reported having been given a diagnosis of AIDS. Of these 217 women, 157 (72%) were listed in the registry as having AIDS. Among the specific AIDS-related conditions reported by three or more women, the sensitivity was highest for tuberculosis (100%), CD4 cell count less than 200 (84%), Mycobacterium avium complex (73%), and Pneumocystis carinii pneumonia (69%), and the positive predictive value was highest for CD4 cell count less than 200 (75%). Among all reported AIDS diagnoses, the kappa statistic was highest for cryptococcosis (0.67) and CD4 cell count less than 200 (0.57). The only statistically significant participant characteristic associated with inaccurate reporting of an AIDS diagnosis was being a current cigarette smoker (adjusted odds ratio = 2.57, 95% confidence interval: 1.17, 5.64). Overall, self-reporting of any AIDS-related condition is fairly accurate, but there is great variability in the accuracy of specific conditions.

Differences in the temporal trends of HIV seroincidence and seroprevalence among sexually transmitted disease clinic patients, 1989-1998: application of the serologic testing algorithm for recent HIV seroconversion

The authors compared temporal trends in the prevalence and incidence of human immunodeficiency virus (HIV) infection based upon 34,866 specimens from patients who attended the San Francisco, California, municipal sexually transmitted disease clinic between 1989 and 1998. HIV infection data were collected during annual blinded HIV serologic surveys. Incidence was determined by applying a serologic testing algorithm for recent HIV seroconversion that uses both a sensitive and a less sensitive enzyme immunoassay to stored HIV positive sera. The HIV seroprevalence declined from 15.2% in 1989 to 7.2% in 1998 (odds ratio per year = 0.92, 95% confidence interval (CI): 0.91, 0.94). Among homosexual men, the HIV prevalence declined from 50.9% in 1989 to 19.9% in 1998 (odds ratio per year = 0.86, 95% CI: 0.85, 0.88). The pooled seroincidence was 1.6% and did not change significantly over time (odds ratio per year = 1.0, 95% CI: 0.98, 1.1). The pooled seroincidence among homosexual men was 6.6% per year and remained steady between 1989 and 1998 (odds ratio per year = 0.99, 95% CI: 0.92, 1.1). During a dramatic, 10-year decline in seroprevalence of HIV infection, the incidence of HIV infection remained remarkably stable.

Crack cocaine use and high-risk behaviors among sexually active black adolescents

The recent spread of crack cocaine use among inner-city teenagers has been accompanied by dramatic increases in juvenile delinquency and sexually transmitted diseases (STDs) among teenagers. This study examined the prevalence of five factors which promote STDs, including human immunodeficiency virus (HIV), among a sample of sexually active black adolescent crack users and non-users from the San Francisco Bay Area. Significant differences were observed between these groups with respect to history of engaging in sexual intercourse under the influence of drugs or alcohol, exchanging sexual favors for drugs or money, condom use in the most recent sexual encounter, and having five or more sexual partners in the last year. Approximately 63% of all respondents reported engaging in at least one of these risk behaviors. In multiple logistic regression analysis, reporting one or more of these STD/HIV risk behaviors was significantly associated with crack use and having one or more relatives who used drugs. Intervention efforts need to address both individual and environmental risk factors in order to reduce teens' risk for STDs, including HIV.

Prevalence of measles susceptibility in hospital staff. Evidence to support expanding the recommendations of the Immunization Practices Advisory Committee

BACKGROUND

In 1989 and 1990, measles reached epidemic proportions in the United States, including several areas of California. Children's Hospital Oakland (Calif), a major health care provider for children in a measles epidemic area of California, reported 131 cases between 1989 and 1991, the largest number ever reported by that institution. In February 1990, four cases of measles were reported among hospital staff. Continued risk of nosocomial infection prompted the development of a program to ensure that all hospital staff were adequately protected against measles.

METHODS

All hospital employees who were unable to document proof of measles immunity were required to be serologically screened for measles antibody and to be vaccinated against measles if they were determined to be nonimmune. Serologic screening was performed in-house with a commercially available enzyme-linked immunosorbent assay measles antibody test. Dates of birth were recorded for all employees screened. Individuals with negative or repeatedly equivocal results were considered to be nonimmune and were vaccinated with trivalent measles-mumps-rubella vaccine.

RESULTS

Between March and June 1990, 1694 staff were serologically tested for measles antibody. Eighty-nine (5.3%) of the employees were considered to have inadequate immunity. Forty (45%) of these susceptible individuals were born before 1957.

CONCLUSIONS

We conclude that the recommendations of the Immunization Practices Advisory Committee should be expanded to include serologic screening or vaccination of hospital personnel who were born before 1957. Serologic screening of hospital staff may be a reasonable alternative to vaccination under certain circumstances.