IN PARTS OF THE UNITED STATES where large-scale screening programs have been instituted and safer sex interventions provided, the prevalence of targeted sexually transmitted infections (STIs) has often substantially declined.1,2 Nonetheless, STIs remain relatively common throughout the nation. One potential contributor to this persistent problem is pockets of infection in persons who may not have regular access to health care such as economically disadvantaged individuals seeking services within local shelters. These community-based organizations assist the homeless—a group comprised of drug abusers, sex workers, those escaping domestic abuse, and the “working poor.” Research has shown that the homeless population is at increased risk of acquiring STIs and bloodborne viruses compared with the general population.3–5 Prevalence of HIV infection among the homeless in developed countries ranges from 2% to 9%—3 to 20 times greater than that of the general population.6 In addition, homeless populations include higher proportions of former prisoners,7 and both homeless and prison populations have high rates of communicable diseases as a result of poor health, illicit drug use, and unsafe sexual practices.8,9 As a group, homeless people are exposed to the highest levels of all social and environmental risk factors that can lead to contracting and transmitting STIs and, thus, pose serious public health challenges.6 Given that an estimated 100 million people worldwide are homeless,10 with 3.5 million homeless people in the United States,8 shelters may be desirable sites for outreach STI screening. However, little is known regarding how receptive shelter clients are to STI testing or the feasibility of using test results to deliver treatment to infected clients.
Thus, the overall goals of the study were 3-fold: 1) to determine the acceptability of STI testing among individuals seeking services at 3 shelters in 2 midsized southeastern cities; 2) to evaluate the prevalence of chlamydia, gonorrhea, syphilis, and HIV among these individuals; and 3) to assess the proportion that would subsequently learn their test results and receive timely and appropriate treatment if warranted.
Sample and Procedure
The current study provides baseline data from an intervention being conducted by the University of Alabama at Birmingham (UAB) Syphilis Elimination Project in collaboration with the Centers for Disease Control and Prevention (CDC). The study's design and protocol were approved by the Institutional Review Boards at UAB and the CDC.
One of the initial goals of the project was to develop collaborative relationships with the state and local health departments and with local community-based organizations (CBOs) in the area of the shelters that had already developed critical relationships and trust with potential participants.11 Staff members of the shelters from which participants were recruited were also elicited as partners in this endeavor. These collaborators assisted the research team with the development of the behavioral questionnaire, were trained to conduct survey interviews, assisted project personnel with blood draws, and provided the medication to treat chlamydia and/or gonorrhea as well as the nurses to deliver oral treatment. The CBOs and each of the shelters were provided with a small monetary compensation for their time and assistance.
From April 2004 to June 2004, adults seeking services (food, clothes, housing, and so on) at the shelters were asked to participate in the study. Potential participants were approached by our research staff when they came into the shelters for lunch (11 am to 1 pm) or dinner (4 pm to 6 pm). Eligibility criteria included being between the ages of 19 and 45, willingness to provide biologic specimens, and provision of informed consent. After the informed consent process, each participant was escorted to a private room within the shelter where he or she completed a 5-minute, face-to-face interview regarding demographic information, sexual practices, and other risk factors. After the interview was completed, each participant was asked to provide a single urine specimen for Chlamydia trachomatis and Neisseria gonorrhoeae testing, a blood specimen for syphilis serologic testing, and an oral fluid specimen for HIV testing. At the time of screening, participants were asked if they were experiencing any symptoms. Testing at all sites was free of charge, voluntary, and confidential; however, respondents were informed that positive test results would be reported to the State Department of Health. Project staff was trained in pre- and posttest counseling for STI screening. All participants were asked to return to the shelter where they were screened to learn their test results in 1 week when the results would be available. Study participants were compensated with a $12 food coupon redeemable at nearby restaurants for their time. No compensation was provided to participants for learning their test results.
Urine for the detection of N. gonorrhoeae and C. trachomatis was placed in GenProbe transport media and transported to the UAB's STD Research Laboratory for testing (GenProbe APTIMA Combo 2) according to the manufacturer's instructions.12 Blood specimens were transported to the Alabama State Department of Health Laboratory for syphilis testing using the Venereal Diseases Research Laboratory test and, if the test was reactive, confirmed using the Treponema pallidum Particle Agglutination Assay (Fujirebio Diagnostics, Malvern, PA). Oral fluid samples were sent directly to the manufacturer for HIV-1 testing (OraSure, Inc.).
Participants who tested positive for chlamydia or gonorrhea were treated at the shelters in a private location by a project nurse in accordance with the CDC's STD Treatment Guidelines.13 Those with chlamydial infection received 1 g azithromycin (single oral dose), whereas those with gonorrhea received 400 mg ofloxacin (single oral dose). Study participants who tested positive for both gonorrhea and chlamydia were treated with regimens effective for each pathogen. All infected participants were instructed to notify their partners and to abstain from sexual intercourse until their sex partners have completed treatment. Those who tested positive for either syphilis or HIV were taken to the local health department by project staff for treatment, partner notification, and follow-up care.
Data Management and Analysis
Questionnaire data were scanned directly into a database using TeleForm software. Both questionnaire data and laboratory results were transported into SPSS (version 12.0; SPSS Inc., Chicago, IL) statistical software package for analysis. Demographic and sexual behaviors were summarized, and gender and city differences were compared by chi-squared analyses for nominal variables and the t-test for continuous variables. Background variables that differed between the 2 cities were considered potential confounders in the outcome analysis and included in a logistic regression.
Of 225 individuals approached in city A shelters, 216 (96%) agreed to participate. Approximately 61% of participants were male. Mean age of the sample was 36 years. Over two thirds (68.5%) of study participants self-identified as being black, 91% reported being heterosexual, and 65% (140 of 216) had engaged in sex within the last 2 months (Table 1).
Of 205 individuals approached for participation in city B, 200 (98%) agreed to participate. The characteristics of persons recruited at the shelter in city B were similar to those found in the 2 shelters in city A, nearly 100 miles away. Nearly two thirds (65.5%) of the sample was male. Mean age was 34 years. Most (88%) of the respondents in county B self-identified as being black, 91% were heterosexual, and 78% (156 of 200) had engaged in sex within the last 2 months (Table 1).
Other selected demographic and self-reported behavioral characteristics across the 2 communities are presented in Table 1. Statistically significant differences were found between the 2 cities for only 3 of the 16 background variables. Participants in city A reported higher rates of drug use before engaging in sex (P <0.001), whereas participants in city B were more often black (P <0.001) and were more likely to have engaged in sexual activity in the previous 2 months (P <0.05). These 3 variables were considered potential confounders and were included in a logistic regression in the outcome analyses.
Sexually Transmitted Infection Prevalence Rates
Among those reporting sexual activity in the past 2 months (n = 296), the combined rate of STIs for both cities was 16.4%: 12.9% (n = 18) in city A and 19.9% (n = 31) in city B. The overall STI rate found for the 2 cities was significantly different (P = 0.04). When comparing individual STI rates across cities, city B had a significantly higher prevalence of chlamydial infections than city A (15.0% vs. 6.4%; P = 0.02; Table 2). There were no significant gender differences for any of the 4 infections detected within each city (P >0.05); however, more males in city B were infected with C. trachomatis (14.3% [14 of 98]) than males in city A (4.1% [3 of 74], P = 0.03). Results from the logistic regression indicated that after controlling for the 3 background variables that differed statistically across the 2 cities (race/ethnicity, sexual activity in the past 2 months, and drug use before engaging in sex), the variable “city” remained significant (odds ratio = 2.95, 95% confidence index = 1.40–6.30; P = 0.005). Among those who reported that they had not engaged in sex in the preceding 2 months (n = 114), STIs were found. The combined rate of STI among these study participants was 5.2%; 7.0% (5 of 71; 2 cases of N. gonorrhoeae and 3 cases of C. trachomatis) in city A and 2.3% (one of 43; one case of C. trachomatis) in city B (data not shown).
At the time of screening, all study participants reported having no signs or symptoms of infection.
Provision of Test Results and Treatment/Follow-Up Care
Overall, 97% of those screened in city A and 98% of individuals screened in city B learned their test results from the project staff (Table 2). Overall, 89% (16 of 18) of infected participants in city A were subsequently counseled and treated, whereas in city B, 94% (29 of 31) of infected persons were counseled and treated. Mean time from screening to treatment was 11.9 days in city A and 14.5 days in city B. Locating information for infected individuals not found by study staff was provided to the health department for follow-up.
This study validates the potential benefits of STI screening for clients of shelters in efforts to reach missed pockets of STIs within communities. This endeavor involved a partnership between university, community-based organizations and state and local health departments. Overall, we found a 16.4% STI prevalence rate (12.9% in city A and 19.9% in city B) among sexually active individuals seeking services at 3 shelters in Alabama. The 3 background variables that differed across the 2 cities (race/ethnicity, sexually active, drug use before sex) were not significant confounders in the outcome analyses; thus, these variables are not contributing to the higher rate of STIs in city B. In addition, we found a 5.2% rate of infection among participants who reported not having sex in the last 2 months.
It is worth emphasizing that all infected persons identified in this study were asymptomatic and would have been unlikely to seek screening or treatment if they had not been approached at the shelters by our outreach staff. Moreover, the number of males infected with chlamydia in city B was nearly 5 times the number of males in city A. This may reflect the fact that at the time this study was conducted, few screening efforts for asymptomatic men were being conducted by the local health department or through outreach activities in this city. Existing screening policies that do not include asymptomatic men are missing an opportunity to significantly reduce infection among this group. The evidence indicates that these policies should be revised.
Our chlamydia and/or gonorrhea prevalence rates are slightly higher than those found in homeless shelters in St. Louis (14.9% vs. 12.3%, respectively).14 Other researchers in Baltimore found an overall prevalence rate of 9.5% for gonorrhea and syphilis among homeless adults and, similar to our study, one third of the sample reported a history of STIs.15 Johnstone and colleagues found that 9% of homeless women attending a gynecologic care center in Chicago tested positive for gonorrhea, 26% were infected with trichomoniasis, and 5% had pelvic inflammatory disease.16 These findings support the effectiveness of screening efforts in this population.
Overall, 97.5% of participants screened learned their test results and 91.5% of the positive cases were treated. Individuals infected with chlamydia and/or gonorrhea who learned their test results were treated at the shelters. Others infected with syphilis and/or HIV who learned their test results were transported to the local health department by project staff for appropriate treatment. We were unable to locate 8.5% of infected participants (11.0% in city A; 6.0% in city B); however, all contact information was provided to the local health department for follow-up.
Admittedly, other researchers have fared slightly better with their outreach screening programs solely for C. trachomatis, with treatment rates as high as 97% in Denver17 and 100% in San Diego.18 Yet, differences in our study population such as the level of poverty and residential instability may have been factors that lowered follow-up rates. Our participants represent a highly transient, difficult-to-reach population. One study of homeless persons with serious mental illnesses did have nearly a 90% return rate, but only 38% of the target population agreed to be tested.19
Irrespective of the current study's limitations, the results clearly attest to the feasibility of outreach testing and demonstrate that the yield is significant in terms of identifying previously untreated STIs in the community. The large number of individuals who were receptive to screening and voluntarily returned to the shelters to learn their test results strongly support the continuation of such efforts to deplete the reservoir of pathogens in this population. Future research is needed to evaluate whether such outreach efforts can be sustained in a cost-effective way.
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