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Background: Updated recommendations for HIV diagnostic laboratory testing published by the Centers for Disease Control and Prevention and the Association of Public Health Laboratories incorporate 4th generation HIV immunoassays, which are capable of identifying HIV infection prior to seroconversion., Objectives: The purpose of this study was to compare turnaround time and cost between 3rd and 4th generation HIV immunoassay-based testing algorithms for initially reactive results., Study Design: The clinical microbiology laboratory database at Mayo Clinic, Rochester, MN was queried for 3rd generation (from November 2012 to May 2014) and 4th generation (from May 2014 to November 2015) HIV immunoassay results. All results from downstream supplemental testing were recorded. Turnaround time (defined as the time of initial sample receipt in the laboratory to the time the final supplemental test in the algorithm was resulted) and cost (based on 2016 Medicare reimbursement rates) were assessed., Results: A total of 76,454 and 78,998 initial tests were performed during the study period using the 3rd generation and 4th generation HIV immunoassays, respectively. There were 516 (0.7%) and 581 (0.7%) total initially reactive results, respectively. Of these, 304 (58.9%) and 457 (78.7%) were positive by supplemental testing. There were 10 (0.01%) cases of acute HIV infection identified with the 4th generation algorithm. The most frequent tests performed to confirm an HIV-positive case using the 3rd generation algorithm, which were reactive initial immunoassay and positive HIV-1 Western blot, took a median time of 1.1 days to complete at a cost of $45.00. In contrast, the most frequent tests performed to confirm an HIV-positive case using the 4th generation algorithm, which included a reactive initial immunoassay and positive HIV-1/-2 antibody differentiation immunoassay for HIV-1, took a median time of 0.4 days and cost $63.25. Overall median turnaround time was 2.2 and 1.5 days, and overall median cost was $63.90 and $72.50 for 3rd and 4th generation algorithms, respectively., Conclusions: Both 3rd and 4th generation HIV immunoassays had similar total numbers of tests performed and positivity rates during the study period. A greater proportion of reactive 4th generation immunoassays were confirmed to be positive, and the 4th generation algorithm identified several cases of acute HIV infection that would have been missed by the 3rd generation algorithm. The 4th generation algorithm had a more rapid turnaround time but higher cost for confirmed positive HIV infections and overall, compared to the 3rd generation algorithm., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Setting: Conventional approaches to tuberculosis (TB) diagnosis and resistance testing are slow. The Xpert® MTB/RIF assay is an emerging molecular diagnostic assay for rapid TB diagnosis, offering results within 2 hours. However, the cost-effectiveness of implementing Xpert in settings with low TB prevalence, such as the United States, is unknown., Objective: We evaluated the cost-effectiveness of incorporating Xpert into TB diagnostic algorithms in the United States compared to existing diagnostics., Design: A decision-analysis model compared current TB diagnostic algorithms in the United States to algorithms incorporating Xpert. Primary outcomes were the costs and quality-adjusted life years (QALYs) accrued with each strategy; cost-effectiveness was represented using incremental cost-effectiveness ratios (ICER)., Results: Xpert testing of a single sputum sample from TB suspects is expected to result in lower total health care costs per patient (US2673) compared to diagnostic algorithms using only sputum microscopy and culture (US2728) and improved health outcomes (6.32 QALYs gained per 1000 TB suspects). Compared to existing molecular assays, implementation of Xpert in the United States would be considered highly cost-effective (ICER US39992 per QALY gained)., Conclusion: TB diagnostic algorithms incorporating Xpert in the United States are highly cost-effective.

Background: The utility of Mycobacterium tuberculosis direct nucleic acid amplification testing (MTD) for pulmonary tuberculosis disease diagnosis in the United States has not been well described., Methods: We analyzed a retrospective cohort of reported patients with suspected active pulmonary tuberculosis in 2008-2010 from Georgia, Hawaii, Maryland, and Massachusetts to assess MTD use, effectiveness, health-system benefits, and cost-effectiveness., Results: Among 2140 patients in whom pulmonary tuberculosis was suspected, 799 (37%) were M. tuberculosis-culture-positive. Eighty percent (680/848) of patients having acid-fast-bacilli-smear-positive specimens had MTD performed; MTD positive-predictive value (PPV) was 98% and negative-predictive value (NPV) was 94%. Nineteen percent (240/1292) of patients having smear-negative specimens had MTD; MTD PPV was 90% and NPV was 88%. Among patients suspected of tuberculosis but not having MTD, smear PPV for lab-confirmed tuberculosis was 77% and NPV 78%. Compared with no MTD, MTD significantly decreased time to diagnosis in patients with smear-positive/MTD-positive specimens, decreased respiratory isolation for patients having smear-positive/MTD-negative/culture-negative specimens, decreased outpatient days of unnecessary tuberculosis medications, and reduced resources expended on contact investigation. While MTD generally cost more than no MTD, incremental cost savings occurred in patients with human immunodeficiency virus (HIV) or homelessness to diagnose or to exclude tuberculosis, and in patients with substance abuse having smear-negative specimens to exclude tuberculosis., Conclusions: MTD improved diagnostic accuracy and timeliness and reduced unnecessary respiratory isolation, treatment, and contact investigations. It was cost saving in patients with HIV, homelessness, or substance abuse, but not in others.

Background: At least 10% of the 56,000 annual new HIV infections in the United States are caused by individuals with acute HIV infection (AHI). It unknown whether the health benefits and costs of routine nucleic acid amplification testing (NAAT) are justified, given the availability of newer fourth-generation immunoassay tests., Methods: Using a dynamic HIV transmission model instantiated with U.S. epidemiologic, demographic, and behavioral data, I estimated the number of acute infections identified, HIV infections prevented, quality-adjusted life years (QALYs) gained, and the cost-effectiveness of alternative screening strategies. I varied the target population (everyone aged 15-64, injection drug users [IDUs] and men who have sex with men [MSM], or MSM only), screening frequency (annually, or every six months), and test(s) utilized (fourth-generation immunoassay only, or immunoassay followed by pooled NAAT)., Results: Annual immunoassay testing of MSM reduces incidence by 9.5% and costs <$10,000 per QALY gained. Adding pooled NAAT identifies 410 AHI per year, prevents 9.6% of new cases, costs $92,000 per QALY gained, and remains <$100,000 per QALY gained in settings where undiagnosed HIV prevalence exceeds 4%. Screening IDUs and MSM annually with fourth-generation immunoassay reduces incidence by 13% with cost-effectiveness <$10,000 per QALY gained. Increasing the screening frequency to every six months reduces incidence by 11% (MSM only) or 16% (MSM and IDUs) and costs <$20,000 per QALY gained., Conclusions: Pooled NAAT testing every 12 months of MSM and IDUs in the United States prevents a modest number of infections, but may be cost-effective given sufficiently high HIV prevalence levels. However, testing via fourth-generation immunoassay every six months prevents a greater number of infections, is more economically efficient, and may obviate the benefits of acute HIV screening via NAAT.

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.

Background and Objectives: The aim of this study was to examine the cost-effectiveness of adding nucleic acid testing (NAT) to serological (antibody and antigen) screening protocols for donated blood in the United States (US) with the purpose of reducing the risks of transfusion-transmission of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV)., Materials and Methods: The costs, health consequences and cost-effectiveness of adding either minipool or individual-donor NAT to serological screening (SS) testing were estimated using a decision-analysis model., Results: With the given modelling assumptions, adding minipool NAT would avoid an estimated 37, 128 and eight cases of HBV, HCV and HIV, respectively, and save approximately 53 additional years of life and 102 additional quality adjusted life years (QALYs) compared with SS, at a net cost of $154 million. SS + minipool NAT - p24 compared with SS alone resulted in an incremental cost-effectiveness ratio of $1.5 million per QALY gained (range in sensitivity analysis $1.0-2.1 million per QALY gained) in this US analysis., Conclusions: The cost effectiveness of adding NAT screening is outside the typical range for most healthcare interventions, but not for established blood safety measures.

The US blood supply has been tested for human immunodeficiency virus-1 (HIV-1) and hepatitis C virus (HCV) using nucleic acid amplification testing (NAT) of pools of small number of samples since early 1999. Since the implementation of NAT under an investigational new drug (IND) application, the results for the yield and false positivity have been remarkably consistent for greater than 2 years of testing even among multiple programmes using two different test methodologies and manufacturers: Gen-Probe/Chiron transcription-mediated amplification (TMA) and Roche polymerase chain reaction. All programmes in the US and Canada use NAT as a criterion for cellular as well as frozen product release. The focus of this paper is to provide an update of the programmes in the US and Canada, provide data in support of p24 antigen replacement by HIV-1 NAT and discuss the projections of residual risk of HIV, HCV and hepatitis B virus (HBV) following NAT and the associated cost/benefit.