Direct Diagnostic Tests for Lyme Disease.

Borrelia burgdorferi was discovered to be the cause of Lyme disease in 1983, leading to seroassays. The 1994 serodiagnostic testing guidelines predated a full understanding of key B. burgdorferi antigens and have a number of shortcomings. These serologic tests cannot distinguish active infection, past infection, or reinfection. Reliable direct-detection methods for active B. burgdorferi infection have been lacking in the past but are needed and appear achievable. New approaches have effectively been applied to other emerging infections and show promise in direct detection of B. burgdorferi infections.

Expanding Hospital Human Immunodeficiency Virus Testing in the Bronx, New York and Washington, District of Columbia: Results From the HPTN 065 Study.

Background: Human immunodeficiency virus (HIV) testing is critical for both HIV treatment and prevention. Expanding testing in hospital settings can identify undiagnosed HIV infections. Methods: To evaluate the feasibility of universally offering HIV testing during emergency department (ED) visits and inpatient admissions, 9 hospitals in the Bronx, New York and 7 in Washington, District of Columbia (DC) undertook efforts to offer HIV testing routinely. Outcomes included the percentage of encounters with an HIV test, the change from year 1 to year 3, and the percentages of tests that were HIV-positive and new diagnoses. Results: From 1 February 2011 to 31 January 2014, HIV tests were conducted during 6.5% of 1621016 ED visits and 13.0% of 361745 inpatient admissions in Bronx hospitals and 13.8% of 729172 ED visits and 22.0% of 150655 inpatient admissions in DC. From year 1 to year 3, testing was stable in the Bronx (ED visits: 6.6% to 6.9%; inpatient admissions: 13.0% to 13.6%), but increased in DC (ED visits: 11.9% to 15.8%; inpatient admissions: 19.0% to 23.9%). In the Bronx, 0.4% (408) of ED HIV tests were positive and 0.3% (277) were new diagnoses; 1.8% (828) of inpatient tests were positive and 0.5% (244) were new diagnoses. In DC, 0.6% (618) of ED tests were positive and 0.4% (404) were new diagnoses; 4.9% (1349) of inpatient tests were positive and 0.7% (189) were new diagnoses. Conclusions: Hospitals consistently identified previously undiagnosed HIV infections, but universal offer of HIV testing proved elusive.

Advances in Serodiagnostic Testing for Lyme Disease Are at Hand.

The cause of Lyme disease, Borrelia burgdorferi, was discovered in 1983. A 2-tiered testing protocol was established for serodiagnosis in 1994, involving an enzyme immunoassay (EIA) or indirect fluorescence antibody, followed (if reactive) by immunoglobulin M and immunoglobulin G Western immunoblots. These assays were prepared from whole-cell cultured B. burgdorferi, lacking key in vivo expressed antigens and expressing antigens that can bind non-Borrelia antibodies. Additional drawbacks, particular to the Western immunoblot component, include low sensitivity in early infection, technical complexity, and subjective interpretation when scored by visual examination. Nevertheless, 2-tiered testing with immunoblotting remains the benchmark for evaluation of new methods or approaches. Next-generation serologic assays, prepared with recombinant proteins or synthetic peptides, and alternative testing protocols, can now overcome or circumvent many of these past drawbacks. This article describes next-generation serodiagnostic testing for Lyme disease, focusing on methods that are currently available or near-at-hand.

Acute HIV Discovered During Routine HIV Screening With HIV Antigen-Antibody Combination Tests in 9 US Emergency Departments.

STUDY OBJECTIVE: Newer combination HIV antigen-antibody tests allow detection of HIV sooner after infection than previous antibody-only immunoassays because, in addition to HIV-1 and -2 antibodies, they detect the HIV-1 p24 antigen, which appears before antibodies develop. We determine the yield of screening with HIV antigen-antibody tests and clinical presentations for new diagnoses of acute and established HIV infection across US emergency departments (EDs). METHODS: This was a retrospective study of 9 EDs in 6 cities with HIV screening programs that integrated laboratory-based antigen-antibody tests between November 1, 2012, and December 31, 2015. Unique patients with newly diagnosed HIV infection were identified and classified as having either acute HIV infection or established HIV infection. Acute HIV infection was defined as a repeatedly reactive antigen-antibody test result, a negative HIV-1/HIV-2 antibody differentiation assay, or Western blot result, but detectable HIV ribonucleic acid (RNA); established HIV infection was defined as a repeatedly reactive antigen-antibody test result and a positive HIV-1/HIV-2 antibody differentiation assay or Western blot result. The primary outcomes were the number of new HIV diagnoses and proportion of patients with laboratory-defined acute HIV infection. Secondary outcomes compared reason for visit and the clinical presentation of acute HIV infection. RESULTS: In total, 214,524 patients were screened for HIV and 839 (0.4%) received a new diagnosis, of which 122 (14.5%) were acute HIV infection and 717 (85.5%) were established HIV infection. Compared with patients with established HIV infection, those with acute HIV infection were younger, had higher RNA and CD4 counts, and were more likely to have viral syndrome (41.8% versus 6.5%) or fever (14.3% versus 3.4%) as their reason for visit. Most patients with acute HIV infection displayed symptoms attributable to acute infection (median symptom count 5 [interquartile range 3 to 6]), with fever often accompanied by greater than or equal to 3 other symptoms (60.7%). CONCLUSION: ED screening using antigen-antibody tests identifies previously undiagnosed HIV infection at proportions that exceed the Centers for Disease Control and Prevention's screening threshold, with the added yield of identifying acute HIV infection in approximately 15% of patients with a new diagnosis. Patients with acute HIV infection often seek ED care for symptoms related to seroconversion.

HIV testing updates and challenges: when regulatory caution and public health imperatives collide.

Numerous improvements in HIV testing technology led recently to the first revision of recommendations for diagnostic laboratory testing in the USA in 25 years. Developments in HIV testing continue to produce tests that identify HIV infection earlier with faster turnaround times for test results. These play an important role in identifying HIV infection during the highly infectious acute phase, which has implication for both patient management and public health interventions to control the spread of HIV. Access to these developments, however, is often delayed by the regulatory apparatus for approval and oversight of HIV testing in the USA. This article summarizes recent developments in HIV diagnostic testing technology, outlines their implications for clinical management and public health, describes current systems of regulatory oversight for HIV testing in the USA, and proposes alternatives that could expedite access to improved tests as they become available.

HIV and hepatitis C virus infection in the United States: whom and how to test.

In the United States, of the 1.1 million persons infected with human immunodeficiency virus (HIV) and the 2.7 million infected with hepatitis C virus (HCV), approximately 16% and 50%, respectively, are unaware of their infection. Highly effective treatments have turned both diseases into manageable conditions, and in the case of hepatitis C, a disease that can be cured. Early diagnosis is imperative so that infected persons can take measures to stay healthy, get into care, benefit from therapy, and reduce the risk of transmission. In this report, we review current recommendations provided by the Centers for Disease Control and Prevention (CDC) and the United States Preventive Services Task Force on whom to screen for HIV and HCV infections, and recommendations from the CDC, the Association of Public Health Laboratories, and the Clinical and Laboratory Standards Institute on how to test for these infections.

Acceptability of home self-tests for HIV in New York City, 2006.

Data from a 2006 telephone survey representative of New York City adults showed that more than half (56.2%) of those aged 18 to 64 years responded favorably to a question about acceptability of a rapid home HIV test. More than two thirds of certain subpopulations at high risk for HIV reported that they would use a rapid home HIV test, but approximately half who expressed interest had indications of financial hardship. The match of acceptability and HIV risk bodes well for self-testing utility, but cost might impede uptake.

Routine HIV screening in two health-care settings--New York City and New Orleans, 2011-2013.

Approximately 16% of the estimated 1.1 million persons living with human immunodeficiency virus (HIV) in the United States are unaware of their infection and thus unable to benefit from effective treatment that improves health and reduces transmission risk. Since 2006, CDC has recommended that health-care providers screen for HIV all patients aged 13-64 years unless prevalence of undiagnosed HIV infection in their patients has been documented to be <0.1%. This report describes novel HIV screening programs at the Urban Health Plan (UHP), Inc. in New York City and the Interim Louisiana Hospital (ILH) in New Orleans. Data were provided by the two programs. UHP screened a monthly average of 986 patients for HIV during January 2011-September 2013. Of the 32,534 patients screened, 148 (0.45%) tested HIV-positive, of whom 147 (99%) received their test result and 43 (29%) were newly diagnosed. None of the 148 patients with HIV infection were previously receiving medical care, and 120 (81%) were linked to HIV medical care. The ILH emergency department (ED) and the urgent-care center (UCC) screened a monthly average of 1,323 patients from mid-March to December 2013. Of the 12,568 patients screened, 102 (0.81%) tested HIV-positive, of whom 100 (98%) received their test result, 77 (75%) were newly diagnosed, and five (5%) had acute HIV infection. Linkage to HIV medical care was successful for 67 (74%) of 91 patients not already in care. Routine HIV screening identified patients with new and previously diagnosed HIV infection and facilitated their linkage to medical care. The two HIV screening programs highlighted in this report can serve as models that could be adapted by other health-care settings.

Evaluation of three rapid screening assays for detection of antibodies to hepatitis C virus.

BACKGROUND: The Centers for Disease Control and Prevention (CDC) estimates that 3.2 million Americans are living with chronic hepatitis C virus (HCV) infection and 50%-70% are unaware of their status. Although therapies are available that can suppress or eliminate infection, identifying persons infected with HCV is challenging. Rapid tests could help identify many of these persons more expeditiously. METHODS: Three manufacturers, Chembio, OraSure, and MedMira, submitted HCV antibody (anti-HCV) rapid screening assays to the CDC for evaluation and comparison with established anti-HCV screening assays. The panel consisted of 1100 specimens drawn during 1997-1999 from persons reporting injection drug use. Sensitivity and specificity were assessed using 2 reference approaches, one based on the reactivity of samples in an anti-HCV screening assay and the other based on CDC HCV testing algorithm. RESULTS: The sensitivities of the Chembio, MedMira, and OraSure assays across the 2 approaches were 96.2%-98.0%, 86.8%-88.3%, and 97.8%-99.3%, respectively. The 3 assays had specificity of 99.5% or higher with no differences between assays. False rapid assay results were associated with human immunodeficiency virus positivity for both approaches for Chembio and MedMira. CONCLUSIONS: Rapid anti-HCV tests can provide sensitive and specific anti-HCV results for high-risk patients.

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.

Cost-effectiveness of pooled nucleic acid amplification testing for acute HIV infection after third-generation HIV antibody screening and rapid testing in the United States: a comparison of three public health settings.

BACKGROUND: Detection of acute HIV infection (AHI) with pooled nucleic acid amplification testing (NAAT) following HIV testing is feasible. However, cost-effectiveness analyses to guide policy around AHI screening are lacking; particularly after more sensitive third-generation antibody screening and rapid testing. METHODS AND FINDINGS: We conducted a cost-effectiveness analysis of pooled NAAT screening that assessed the prevention benefits of identification and notification of persons with AHI and cases averted compared with repeat antibody testing at different intervals. Effectiveness data were derived from a Centers for Disease Control and Prevention AHI study conducted in three settings: municipal sexually transmitted disease (STD) clinics, a community clinic serving a population of men who have sex with men, and HIV counseling and testing sites. Our analysis included a micro-costing study of NAAT and a mathematical model of HIV transmission. Cost-effectiveness ratios are reported as costs per quality-adjusted life year (QALY) gained in US dollars from the societal perspective. Sensitivity analyses were conducted on key variables, including AHI positivity rates, antibody testing frequency, symptomatic detection of AHI, and costs. Pooled NAAT for AHI screening following annual antibody testing had cost-effectiveness ratios exceeding US$200,000 per QALY gained for the municipal STD clinics and HIV counseling and testing sites and was cost saving for the community clinic. Cost-effectiveness ratios increased substantially if the antibody testing interval decreased to every 6 months and decreased to cost-saving if the testing interval increased to every 5 years. NAAT was cost saving in the community clinic in all situations. Results were particularly sensitive to AHI screening yield. CONCLUSIONS: Pooled NAAT screening for AHI following negative third-generation antibody or rapid tests is not cost-effective at recommended antibody testing intervals for high-risk persons except in very high-incidence settings.

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.

HIV Diagnostics: Current Recommendations and Opportunities for Improvement.

Profound changes in technology have revolutionized laboratory testing for human immunodeficiency virus (HIV) since the first laboratory enzyme immunoassays that detected only immunoglobulin G (IgG) antibodies. Instrumented fourth-generation random-access chemiluminescent assays are now recommended for initial screening because they become reactive in as little as 2 weeks after infection. Using HIV-1 RNA viral load assays after a reactive initial test could confirm infection and provide useful clinical information. Early initiation of antiretroviral therapy and use of preexposure prophylaxis can alter the evolution of biomarkers and assay reactivity, leading to ambiguous test results.

Comparing the costs of HIV screening strategies and technologies in health-care settings.

OBJECTIVES: In 2006, the Centers for Disease Control and Prevention (CDC) recommended routine human immunodeficiency virus (HIV) screening for people aged 13 to 64 years in all U.S. health-care settings. Earlier recommendations focused on those at high risk for HIV and included more extensive pretest counseling. HIV screening may also involve either rapid or conventional testing. The purpose of this research was to estimate the costs of these different testing procedures and the cost per HIV-infected patient correctly receiving test results in three health-care scenarios that illustrated these policy differences. METHODS: The study estimated the costs of rapid and conventional HIV testing in the following scenarios: (1) sexually transmitted disease (STD) clinic counseling and testing (CT), (2) STD clinic screening, and (3) emergency department (ED) screening. Costs were estimated from the provider perspective in 2006 dollars. A decision analytic model was developed to estimate the cost per HIV-infected patient notified of test results using the two testing procedures in the three scenarios. RESULTS: Although the complete rapid testing procedure was more expensive than conventional testing, the cost per HIV-infected patient receiving test results was lower for the rapid test compared with conventional testing in all scenarios. Per-patient costs of receiving results were lowest in the ED screening scenario and highest in the STD CT scenario. These costs were sensitive to changes in test costs, HIV prevalence, and return rates following conventional tests. CONCLUSION: HIV screening in general health-care settings is economically feasible, particularly with rapid tests that lower the cost of HIV-infected patients receiving their test results.

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 CDC's 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.

It's all in the timing: Acceptability of a financial incentive intervention for linkage to HIV care in the HPTN 065 (TLC-Plus) study.

The HPTN 065 (TLC-Plus) study tested the feasibility and effectiveness of using financial incentives (FIs) to increase linkage to care (L2C) among individuals with newly diagnosed HIV and those out of care in the Bronx, NY and Washington, DC. Qualitative data collection with a subset of participating patients and staff focused on experiences with and attitudes about the FI intervention. Semi-structured interviews were conducted with 15 patients and 14 site investigators. Four focus group discussions were conducted with a total of 15 staff members. The use of FIs for L2C was generally viewed favorably. Patients were grateful and benefited financially, but sites had some challenges implementing the program. Challenges included the timing and sensitive introduction of the intervention immediately after an HIV diagnosis, negative attitudes towards paying people for health behaviors, and the existence and strength of existing linkage programs. Future programs should consider optimal timing and presentation of FIs.

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.

Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings.

These recommendations for human immunodeficiency virus (HIV) testing are intended for all health-care providers in the public and private sectors, including those working in hospital emergency departments, urgent care clinics, inpatient services, substance abuse treatment clinics, public health clinics, community clinics, correctional health-care facilities, and primary care settings. The recommendations address HIV testing in health-care settings only. They do not modify existing guidelines concerning HIV counseling, testing, and referral for persons at high risk for HIV who seek or receive HIV testing in nonclinical settings (e.g., community-based organizations, outreach settings, or mobile vans). The objectives of these recommendations are to increase HIV screening of patients, including pregnant women, in health-care settings; foster earlier detection of HIV infection; identify and counsel persons with unrecognized HIV infection and link them to clinical and prevention services; and further reduce perinatal transmission of HIV in the United States. These revised recommendations update previous recommendations for HIV testing in health-care settings and for screening of pregnant women (CDC. Recommendations for HIV testing services for inpatients and outpatients in acute-care hospital settings. MMWR 1993;42[No. RR-2]:1-10; CDC. Revised guidelines for HIV counseling, testing, and referral. MMWR 2001;50[No. RR-19]:1-62; and CDC. Revised recommendations for HIV screening of pregnant women. MMWR 2001;50[No. RR-19]:63-85). Major revisions from previously published guidelines are as follows: For patients in all health-care settings HIV screening is recommended for patients in all health-care settings after the patient is notified that testing will be performed unless the patient declines (opt-out screening). Persons at high risk for HIV infection should be screened for HIV at least annually. Separate written consent for HIV testing should not be required; general consent for medical care should be considered sufficient to encompass consent for HIV testing. Prevention counseling should not be required with HIV diagnostic testing or as part of HIV screening programs in health-care settings. For pregnant women HIV screening should be included in the routine panel of prenatal screening tests for all pregnant women. HIV screening is recommended after the patient is notified that testing will be performed unless the patient declines (opt-out screening). Separate written consent for HIV testing should not be required; general consent for medical care should be considered sufficient to encompass consent for HIV testing. Repeat screening in the third trimester is recommended in certain jurisdictions with elevated rates of HIV infection among pregnant women.