Bernard M. Branson

Reducing the risk of sexual HIV transmission: quantifying the per-act risk for HIV on the basis of choice of partner, sex act, and condom use.

Background Sexual acquisition of HIV is influenced by choice of partner, sex act, and condom use. However, current risk-reduction strategies focus mainly on condom use. Goal To estimate the contribution of choice of partner, sex act, and condom use on the per-act relative and absolute risks for HIV infection. Study Design Per-act relative risk for HIV infection was calculated with use of estimates of HIV prevalence, risk of condom failure, HIV test accuracy, and per-act risk of HIV transmission for different sex acts. Absolute risks were calculated on the basis of these relative risk estimates. Results Choosing a partner who tested negative instead of an untested partner reduced the relative risk of HIV infection 47-fold; using condoms, 20-fold; and choosing insertive fellatio rather than insertive anal sex, 13-fold. Choosing one risk-reduction behavior substantially reduces absolute risk of HIV infection for heterosexuals but not for men who have sex with men. Conclusion Clarifying the magnitude of risk associated with different choices may help people make effective and sustainable changes in behavior.

Overcoming barriers to HIV testing: preferences for new strategies among clients of a needle exchange, a sexually transmitted disease clinic, and sex venues for men who have sex with men:

Objective: To determine strategies to overcome barriers to HIV testing among persons at risk. Methods: We developed a survey that elicited testing motivators, barriers, and preferences for new strategies among 460 participants at a needle exchange, three sex venues for men who have sex with men, and a sexually transmitted disease clinic. Results: Barriers to testing included factors influenced by individual concern (fear and discrimination); by programs, policies, and laws (named reporting and inability to afford treatment); and by counseling and testing strategies (dislike of counseling, anxiety waiting for results, and venipuncture). The largest proportions of participants preferred rapid testing strategies, including clinic‐based testing (27%) and home selftesting (20%); roughly equal proportions preferred oral fluid testing (18%), urine testing (17%), and standard blood testing (17%). One percent preferred home specimen collection. Participants who had never tested before were significantly more likely to prefer home self‐testing compared with other strategies. Blacks were significantly more likely to prefer urine testing. Conclusions: Strategies for improving acceptance of HIV counseling and testing include information about access to anonymous testing and early treatment. Expanding options for rapid testing, urine testing, and home self‐testing; providing alternatives to venipuncture; making pretest counseling optional; and allowing telephone results disclosure may encourage more persons to learn their HIV status.

Performance of an oral fluid rapid HIV-1/2 test: experience from four CDC studies.

Objective:To evaluate the performance of a rapid HIV antibody test used with whole blood and oral fluid in settings where the test is likely to be used. Design:In four separate studies, we compared the accuracy of the rapid test performed on whole blood and oral fluid specimens with the results of conventional HIV tests. Methods:Oral fluid and whole blood from persons of unknown HIV status recruited from clinics, labor and delivery units, and outreach venues were tested with the OraQuick Advance rapid HIV-1/2 antibody test. Sensitivity and specificity were compared with results of the enzyme immunoassay (EIA) and Western blot algorithm used by the study sites. Results:OraQuick sensitivity was 99.7% with whole blood and 99.1% with oral fluid from 327 persons who were HIV antibody positive by the conventional algorithm. OraQuick specificity was 99.9% with whole blood and 99.6% with oral fluid from 12 010 HIV-negative persons; EIA specificity was 99.7%. A cluster of 16 false-positive oral fluid tests occurred in one study, in which specificity was lower (99.0%) than in the other three studies (99.6–99.8%). Conclusions:In diverse settings in four studies, the OraQuick test showed high sensitivity and specificity for HIV antibody in whole blood and oral fluid specimens. Slightly more false-positive and false-negative results occurred with oral fluid than with whole blood, but performance with both specimen types was similar to, or better than, that of conventional EIAs.

Detecting Unsuspected HIV Infection With a Rapid Whole-Blood HIV Test in an Urban Emergency Department

Objective:To evaluate and compare HIV screening and provider-referred diagnostic testing as strategies for detecting undiagnosed HIV infection in an urban emergency department (ED). Methods:From January 2003 through April 2004, study staff offered HIV screening with rapid tests to ED patients regardless of risks or symptoms. ED providers could also refer patients for diagnostic testing. Patients aged 18 to 54 years without known HIV infection were eligible. Results:Of 4849 eligible patients approached for screening, 2824 (58%) accepted and were tested; 414 (95%) of 436 provider-referred patients accepted and were tested. Thirty-five (1.2%) screened patients and 48 (11.6%) provider-referred patients were infected with HIV (P < 0.001). Of these, 18 (51%) screened patients and 24 (50%) referred patients reported no traditional risk factors; 27 (77%) screened patients and 38 (79%) referred patients entered HIV care. Of HIV-infected patients with CD4 cell counts available, 14 (45%) of 31 screened patients and 37 (82%) of 45 provider-referred patients had <200 cells/μL (P < 0.001). Conclusions:ED screening detects HIV infection and links to care patients who may not be tested through risk- or symptom-based strategies. The diagnostic yield was higher among provider-referred patients, but screening detected patients earlier in the course of disease.

Opt-Out Testing for Human Immunodeficiency Virus in the United States: Progress and Challenges

The Centers for Disease Control and Prevention (CDC) has recommended human immunodeficiency virus (HIV) testing for all persons aged 13 to 64 years in all health care settings. Signed consent would not be required and counseling with referral would be managed as it is for other serious conditions. The goal of the recommendations is to promote earlier entry into care to reduce unnecessary mortality and facilitate prevention by behavioral changes that accompany knowledge of serostatus. Concerns about the change include laws in some states that mandate signed consent and counseling, a perception that counseling is an effective prevention strategy, variability in payment coverage for the test, concerns about the stigma and discrimination that may accompany the HIV diagnosis, and the possibility that other testing policies would be more effective. Eleven of 16 states have changed legislation to reduce barriers to testing, 35 of 74 national professional societies have endorsed the new recommendations, and multiple demonstration projects have shown feasibility. Metrics to evaluate the health outcomes of the CDCs recommendations for HIV testing have been defined, but the data necessary to determine the effects on early entry into care, the actual reduction in disease incidence, and the unanticipated consequences are not yet available.

A meta-analysis of the effectiveness of alternative HIV counseling and testing methods to increase knowledge of HIV status

Background:Alternatives to conventional HIV counseling and testing (HIV-CT) have been used to improve receipt of HIV test results. Objectives:To determine the effectiveness of alternative HIV-CT methods on the receipt of HIV test results. Methods:Studies were identified by a systematic search of the literature using English-language databases from 1990 to 2005. Studies were included if they used an alternative method for HIV-CT, reported the receipt of HIV test results and had a comparison group. Pooled effect sizes [risk ratios (RR)] were calculated using a random effects model. Results:Seventeen effect sizes (k) were included n = 21 096). Alternative HIV-CT methods included rapid testing (k = 12), oral fluid testing (k = 2), home testing (k = 1), and telephone post-test counseling (k = 2). All alternatives except for oral fluid testing significantly increased receipt of results compared with conventional testing. In stratified analysis, rapid testing was most effective [RR, 1.80; 95% confidence interval (CI), 1.46–2.22] followed by telephone post-test counseling (RR, 1.38. 95% CI, 1.24–1.47). Conclusions:There is strong evidence that clients are substantially more likely to receive their HIV test results with rapid testing than with conventional tests or other alternatives. Therefore, to increase knowledge of HIV status, rapid testing is preferable in settings with low rates of return for test results.

Results of a Rapid HIV Screening and Diagnostic Testing Program in an Urban Emergency Department

STUDY OBJECTIVE We describe outcomes of a rapid HIV testing program integrated into emergency department (ED) services, using existing staff. METHODS From April 2005 through December 2006, triage nurses in an urban ED offered HIV screening to medically stable patients aged 12 years or older. Clinicians could also order diagnostic testing according to presenting signs and symptoms and suspicion of HIV-related illness. Nurses obtained consent, performed rapid testing, and disclosed negative test results. Clinicians disclosed positive test results and arranged follow-up. Outcome measures included number and proportion of visits during which screening was offered, accepted, and completed; number of visits during which diagnostic testing was completed; and number of patients with confirmed new HIV diagnosis and their CD4 counts. RESULTS HIV screening and diagnostic testing were completed in 9,466 (8%) of the 118,324 ED visits (14.2% of the 60,306 unique patients were tested at least once). Screening was offered 45,159 (38.2%) times, accepted 21,626 (18.3%) times, and completed 7,923 (6.7%) times; diagnostic testing was performed 1,543 (1.3%) times. Fifty-five (0.7%) screened patients and 46 (3.0%) of those completing diagnostic testing had confirmed positive HIV test results. Median CD4 count was 356 cells/microL among screened patients and 99 cells/microL among those who received diagnostic testing. CONCLUSION Although existing staff was able to perform HIV screening and diagnostic testing, screening capacity was limited and the HIV prevalence was low in those screened. Diagnostic testing yielded a higher percentage of new HIV diagnoses, but screening identified greater than 50% of those found to be HIV positive, and the median CD4 count was substantially higher among those screened than those completing diagnostic testing.

The future of HIV testing.

HIV testing is the essential entry point for both treatment and prevention. The need to identify acute HIV infection (the period immediately after HIV acquisition, when persons are most infectious) and HIV-2 infection, which does not respond to many first-line antiretroviral agents, poses challenges for the traditional algorithm of Western blot confirmation after a repeatedly reactive antibody screening test. Immunoassays that detect antibodies earlier, tests for HIV RNA, and combination assays that screen simultaneously for both p24 antigen and HIV antibody are now approved for HIV diagnosis by the Food and Drug Administration. A revised testing algorithm can address the challenges posed by acute infection, HIV-2 infection, and the shortcomings of the Western blot. These new diagnostic strategies will allow earlier more accurate identification of infected persons so that they can benefit from effective treatment and also enhance abilities to focus prevention efforts where HIV transmission is most active.

State of the Art for Diagnosis of HIV Infection

Diagnostic tests for human immunodeficiency virus (HIV) infection have undergone considerable evolution since the first enzyme immunoassay (EIA) and Western blot were introduced 2 decades ago. Newer methods detect infection sooner and yield results much faster. Rapid tests represent a major advance for HIV screening in the United States. Six rapid tests for detection of HIV antibody have been approved by the Food and Drug Administration (FDA) since November 2002. Four of these tests can be done in point-of-care and nonclinical settings because they use whole blood or oral fluid and are simple to perform. An assay for detection of HIV-1 RNA has been approved by the FDA to detect HIV infection before seroconversion has occurred and to confirm results of reactive screening tests; pooled testing of specimens for HIV-1 RNA has increased the cost-effectiveness of this screening tool. These new testing technologies offer unique opportunities to diagnose HIV infection among the estimated 252,000-312,000 persons in the United States who are currently unaware they are infected.

Evaluation of the Performance Characteristics of 6 Rapid HIV Antibody Tests

BACKGROUND Since 2002, the US Food and Drug Administration has approved 6 rapid human immunodeficiency virus (HIV) tests for use in the United States. To date, there has been no direct comparison of the performance of all 6 tests. METHODS Persons known to be HIV-infected and persons who sought HIV testing at 2 clinical sites in Los Angeles, California, were recruited for evaluation of 6 rapid HIV tests with whole blood, oral fluid, serum, and plasma specimens. Sensitivity and specificity of the rapid tests were compared with viral lysate and immunoglobulin (Ig) M-sensitive peptide HIV enzyme immunoassays (EIAs). RESULTS A total of 6282 specimens were tested. Sensitivity was >95% and specificity was >99% for all rapid tests. Compared with the IgM-sensitive EIA, rapid tests gave false-negative results with an additional 2-5 specimens. All rapid tests had statistically equivalent performance characteristics, based on overlapping confidence intervals for sensitivity and specificity, compared with either conventional EIA. CONCLUSIONS All 6 rapid tests have high sensitivity and specificity, compared with that of conventional EIAs. Because performance was similar for all tests and specimen types, other characteristics, such as convenience, time to result, shelf life, and cost will likely be determining factors for selection of a rapid HIV screening test for a specific application.