THE CENTERS FOR DISEASE CONTROL and Prevention (CDC) recently announced the Serostatus Approach to Fighting the HIV Epidemic (SAFE) and the Advancing HIV Prevention Initiative.1,2 These initiatives place new emphasis on HIV partner notification (PN). However, public health HIV PN programs currently affect a minority of persons with newly diagnosed HIV in the United States,3 few data are available on the success of HIV PN programs,4 and national data on HIV PN outcomes have not been systematically evaluated and published. To assess the case-finding success of current U.S. public health HIV PN activities, we collated data for public health agencies in high AIDS morbidity areas of the United States.
Materials and Methods
We surveyed HIV PN programs in jurisdictions reporting ≥200 AIDS cases5 in 2001, collecting information about the organization of each area’s PN program, the sex and HIV risk factors of persons reported with AIDS, and aggregate 2001 data on numbers of persons interviewed for PN and PN outcomes. All surveys were conducted by mail. No effort was made to assess how PN data collection varied across jurisdictions surveyed. We calculated the number of HIV-infected persons that health departments needed to interview to identify 1 previously undiagnosed case of HIV (number needed to interview [NNTI]) by dividing the number of persons with HIV interviewed for PN by the number of new cases of HIV detected among those persons’ sex or needle-sharing partners. Univariate tests of association were performed using the 2-sided chi-squared test. Correlations between continuous variables were evaluated using the Pearson correlation coefficient. Statistical procedures were performed using SAS (SAS Institute, Cary, NC).
Representatives of health departments in all 39 jurisdictions reporting ≥200 AIDS cases in 2001 were contacted. Eleven of these reported that they had no data on the number of persons receiving PN services or PN outcomes. Seven jurisdictions in 6 states could only provide statewide data; these were included in the analysis. Thus, data were available from 27 health departments responsible for 28 (72%) of 39 jurisdictions. Nonparticipating jurisdictions were located in 5 states in all 4 regions of the country (West, East, South, and Midwest); the median number of AIDS cases reported in 2001 among participating and nonparticipating sites were 459 (range, 208–6152) and 320 (range, 200–1657), respectively. Participating jurisdictions reported a combined total of 24,006 AIDS cases in 2001. This number represents 58% of the total 41,755 cases reported nationwide, 69% of the 34,732 cases reported from metropolitan areas >500,000, and 86% of 27,771 AIDS cases reported by the 39 jurisdictions offered study participation. Table 1 summarizes the characteristics of the 27 health agencies surveyed.
Twenty-five (93%) of the 27 jurisdictions reported that HIV PN services were routinely provided to persons testing positive in publicly funded HIV testing sites; 12 jurisdictions (44%) provided HIV PN services outside of public health sites only when providers contacted the health department to request assistance. Routine PN was limited to public counseling and testing venues in 4 (22%) of 18 areas with <1000 reported HIV cases and 4 (80%) of 5 areas with >1000 reported cases (P = 0.03, Fisher exact test).
Twenty-two (82%) of 27 jurisdictions provided data on both the number of HIV cases reported and the number interviewed for PN (Table 2). Among 20,353 cases reported in these areas, 6565 (32%) were interviewed. The proportion of persons interviewed in each jurisdiction was associated with the proportion of AIDS cases reported in men having sex with men (MSM) (r = 0.44, P = 0.04) and was inversely associated with the number of HIV cases reported (r = -0.44, P = 0.04).
Nineteen jurisdictions reported the number of HIV-infected persons who requested or accepted assistance notifying at least 1 partner; among the total 6906 persons interviewed, 2823 (41%) requested assistance notifying at least 1 partner, although this proportion was highly variable. Jurisdictions with smaller proportions of AIDS cases in MSM reported a higher proportion of cases accepting HIV PN assistance (r = -0.46, P = 0.05).
Twenty-three jurisdictions (85%) reported complete information on the number of persons interviewed for PN and the outcome of PN efforts (Table 2). Among 6394 potentially exposed partners in these areas, 1232 (19%) had been previously diagnosed with HIV, 612 (10%) were newly HIV-diagnosed, 2037 (32%) tested HIV-negative, and 2513 (39%) were not successfully notified, were notified but refused HIV testing and denied previous HIV diagnosis, or did not have a PN outcome recorded.
Among 26 jurisdictions, 8349 persons interviewed for HIV PN named 604 partners who were newly HIV-diagnosed (NNTI = 13.8). PN success was highly variable. Areas with higher proportions of AIDS cases in MSM tended to have higher NNTIs than areas with fewer cases in MSM (r = 0.46, P = 0.01). In areas in which ≥50% of HIV cases occurred among MSM, 3911 infected persons were interviewed to identify 108 new cases (NNTI = 36.2), whereas in areas where MSM comprised <50% of AIDS cases, 4438 persons with HIV were interviewed to identify 496 new cases (NNTI = 8.9).
We collated public health program statistics from U.S. metropolitan areas that reported ≥200 AIDS cases in 2001 to evaluate the coverage and case-finding success of HIV PN. We found that only approximately one third of newly diagnosed HIV cases were interviewed for PN and that the overall NNTI for all jurisdictions combined was 13.8. Coverage and case-finding success were highly variable, with lower levels of coverage in areas with the greatest burden of disease and poorer case-finding outcomes in areas with larger proportions of AIDS cases among MSM.
The NNTI that we documented corresponds to the higher end of the range reported by single-city or -state studies (NNTI = 4.2–13.3)4,6 and is similar to the NNTI value of 12.7 reported in a multicenter European study of 356 persons with HIV who received PN services.7 Using a base case assumption that NNTI = 9.3, Varghese performed a cost-effectiveness analysis that concluded that HIV PN was cost-effective.8 In that study, the cost per case of HIV identified was estimated to be $2638 in 1997 U.S. dollars. The CDC currently advocates routine testing in populations with HIV seroprevalences ≥1%,9,10 and cost-effectiveness studies have supported HIV testing programs with estimated costs per case of HIV detected between $4200 and $16,000.11,12 Because the median NNTI we observed among U.S. PN programs is higher than that assumed by Varghese, our results suggest that HIV PN as currently practiced in the United States may be less cost-effective than suggested in that study. Nevertheless, HIV PN services probably operate within the cost-effectiveness range of other publicly supported HIV case-finding efforts, although there is considerable variability in success in different jurisdictions.
We found that fewer persons requested assistance with PN and that case-finding was less successful in areas where higher proportions of AIDS cases occurred in MSM. This finding is consistent with recent studies that show poor PN outcomes among MSM with syphilis13,14 and some previous reports on HIV PN15–17 but not others.6,18 Factors that may contribute to relatively poor PN outcomes among MSM include the relative frequency of anonymous sexual partnerships,19,20 mistrust of public health authorities, and possibly an institutional culture in some PN programs that emphasizes client satisfaction over HIV case-finding.21 Despite the relatively poor success of HIV PN among MSM, areas in which a larger proportion of AIDS cases occurred in MSM reported interviewing higher proportions of cases. This suggests that areas in which PN might have the greatest impact frequently provide PN services less frequently. At present, the data supporting PN are strongest among injection drug users (IDU) and heterosexuals, and widespread application of PN for these populations seems warranted. More research is needed to gauge the success of PN among MSM and to identify, develop, and promote successful PN programs for that population. Additional efforts will also be needed to overcome resistance to PN among some MSM community groups, and to promote PN as a normal and desirable part of HIV care and prevention.
Our study has several limitations. First, we did not conduct a prospectively designed study of PN effectiveness. We collated routinely collected public health data. Although this allowed us to assess a large component of the U.S. HIV PN system as it exists, some of the variability we observed may reflect differences in procedures and outcome classification in different jurisdictions. Second, we cannot estimate the proportion of persons identified through PN efforts that would have been notified and tested in the absence of such efforts. Studies conducted primarily among MSM in the late 1980s to early 1990s reported that 27% to 70% had notified at least 1 past partner after testing HIV-positive,22,23 whereas a small randomized trial found that STD clinic patients diagnosed with HIV notified only 6% of their potentially exposed partners in the absence of public health assistance.24 Contemporary, representative data do not exist on this issue, but these older studies suggest that PN often results in earlier diagnosis than would occur without this service. Third, we analyzed aggregate, not individual-level, PN outcomes. Consequently, we report only ecologic associations between PN outcomes and HIV risks. Finally, although study areas reported 69% of all AIDS cases in metropolitan areas >500,000 in the United States in 2001, some health departments we contacted had no data on HIV PN outcomes, perhaps biasing our results. It seems likely that areas that did not participate in the study, all of which reported that they had no means of determining the number of persons interviewed for PN or PN outcomes, have less successful PN programs. As a result, we suspect that our study overestimates the coverage and case-finding success of HIV PN in the United States.
In summary, we found that public health HIV PN programs in the United States affect a minority of persons with HIV and that these programs are highly variable in their success. Process outcomes suggest that these programs identify new cases of HIV, particularly in areas with significant epidemics in heterosexual and IDU populations. Based on these findings, we believe that HIV PN programs should be expanded, but that they require better ongoing efforts to assess, target, and improve services.
1. Centers for Disease Control and Prevention. Advancing HIV prevention: New strategies for a changing epidemic. MMWR Morb Mortal Wkly Rep 2003; 52:1–4.
2. Janssen RS, Holtgrave DR, Valdiserri RO, Shepherd M, Gayle HD, De Cock KM. The serostatus approach to fighting the HIV epidemic: Prevention strategies for infected individuals. Am J Public Health 2001; 91:1019–1024.
3. Golden MR, Hogben M, Handsfield HH, St. Lawrence JS, Potterat JJ, Holmes KK. Partner notification for HIV and STD in the United States: Low coverage for gonorrhea, chlamydial infection, and HIV. Sex Transm Dis 2003; 30:490–496.
4. Golden MR. HIV partner notification: A neglected prevention intervention [Editorial]. Sex Transm Dis 2002; 29:472–475.
5. HIV/AIDS Surveillance Report 2001. Atlanta: Centers for Disease Control and Prevention; 2002:13(no 2).
6. Centers for Disease Control and Prevention. Partner counseling and referral services to identify persons with undiagnosed HIV—North Carolina 2001. MMWR Morb Mortal Wkly Rep 2003; 52:1181–1184.
7. Recently diagnosed sexually HIV-infected patients: Seroconversion interval, partner notification period and a high yield of HIV diagnoses among partners. QJM 2001; 94:379–390.
8. Varghese B, Peterman TA, Holtgrave DR. Cost-effectiveness of counseling and testing and partner notification: A decision analysis. AIDS 1999; 13:1745–1751.
10. Centers for Disease Control and Prevention. Revised guidelines for HIV counseling, testing, and referral. MMWR Recomm Rep 2001; 50 (RR-19):1–57.
11. Lurie P, Avins AL, Phillips KA, Kahn JG, Lowe RA, Ciccarone D. The cost-effectiveness of voluntary counseling and testing of hospital inpatients for HIV infection. JAMA 1994; 272:1832–1838.
12. Phillips KA, Fernyak S. The cost-effectiveness of expanded HIV counselling and testing in primary care settings: A first look. AIDS 2000; 14:2159–2169.
13. Chen JL, Kodagoda D, Lawrence AM, Kerndt PR. Rapid public health interventions in response to an outbreak of syphilis in Los Angeles. Sex Transm Dis 2002; 29:277–284.
14. Kohl KS, Farley TA, Ewell J, Scioneaux J. Usefulness of partner notification for syphilis control. Sex Transm Dis 1999; 26:201–207.
15. Potterat JJ, Phillips-Plummer L, Muth SQ, et al. Risk network structure in the early epidemic phase of HIV transmission in Colorado Springs. Sex Transm Infect 2002; 78 (suppl 1):i159–163.
16. Spencer NE, Hoffman RE, Raevsky CA, Wolf FC, Vernon TM. Partner notification for human immunodeficiency virus infection in Colorado: Results across index case groups and costs. Int J STD AIDS 1993; 4:26–32.
17. Schwarcz S, McFarland W, Delgado V, et al. Partner notification for persons recently infected with HIV: Experience in San Francisco. J Acquir Immun Defic Syndr 2001; 28:403–404.
18. Toomey KE, Peterman TA, Dicker LW, Zaidi AA, Wroten JE, Carolina J. Human immunodeficiency virus partner notification. Cost and effectiveness data from an attempted randomized controlled trial. Sex Transm Dis 1998; 25:310–316.
19. Whittington WL, Collis T, Dithmer-Schreck D, et al. Sexually transmitted diseases and human immunodeficiency virus-discordant partnerships among men who have sex with men. Clin Infect Dis 2002; 35:1010–1017.
20. Binson D, Woods WJ, Pollack L, Paul J, Stall R, Catania JA. Differential HIV risk in bathhouses and public cruising areas. Am J Public Health 2001; 91:1482–1486.
21. Potterat JJ. Partner notification for HIV: running out of excuses. Sex Transm Dis 2003; 30:89–90.
22. Marks G, Richardson JL, Ruiz MS, Maldonado N. HIV-infected men’s practices in notifying past sexual partners of infection risk. Public Health Rep 1992; 107:100–105.
23. Perry SW, Card CA, Moffatt M Jr, Ashman T, Fishman B, Jacobsberg LB. Self-disclosure of HIV infection to sexual partners after repeated counseling. AIDS Educ Prev 1994; 6:403–411.
24. Landis SE, Schoenbach VJ, Weber DJ, et al. Results of a randomized trial of partner notification in cases of HIV infection in North Carolina. N Engl J Med 1992; 326:101–106.