Rapid Testing Algorithm Performance in a Low-Prevalence Environment.

BACKGROUND: The performance of a statewide HIV rapid test algorithm (RTA) in a low-prevalence setting (0.71%) was examined for 3 years. METHODS: An initial rapid screening by HIV-1/2 Ag/Ab Combo test (RT#1) with Ab verification using a second, different rapid test (RT#2) was conducted. Clinic referral was immediate for antigen-only-positive screens. Antibody-positive screens were confirmed by RT#2. Specimens were collected following discordant RTA results (initially Ab-POS by RT#1, but negative on RT#2) and tested in accordance with the current Centers for Disease Control and Prevention/Association of Public Health Laboratories-based HIV diagnostic algorithm supplemented by a quantitative viral load whenever possible. RESULTS: Of 310,785 tests performed, 2400 preliminary positive screens were identified; 2191 (91.8%) confirmed by RT#2. Of 13 Determine Combo AG-POS results identified, only 1 confirmed positive. Of the remaining 196 discordant results, 182 (92.9%) were uninfected, including 13 with AG-POS/AB-POS results. Of 14 true positives (7.1%) identified after discordant RTA results, the average quantitative HIV-1 viral load was 277,385 copies/mL, but 5 (35.7%) of 14 had viral loads <1000 copies/mL. Among the 2191 "presumptive positive" by RTA, 3 false-positive (FP) RTAs were reported (both rapid tests having positive results, while the HIV-1/2 Ag/Ab assay and quantitative HIV-1 viral load showed negative results). CONCLUSIONS: The RTA was effective in predicting true-positive HIV test results and facilitating linkage to care. Discordant results were infrequent. Fingerstick DC Ag detection identified a single early infection. Many discordant cases that were subsequently positive were associated with viral loads <1000 copies/mL.

Results of a Hepatitis C Virus Screening Program of the 1945-1965 Birth Cohort in a Large Emergency Department in New Jersey.

BACKGROUND: Persons born between 1945 and 1965 account for an estimated 81% of those infected with hepatitis C virus (HCV) in the United States. However, up to 60% remain undiagnosed. Prior studies have reported HCV screening results from large urban emergency departments. METHODS: This is a retrospective cohort study of patients in the 1945-1965 birth cohort tested for HCV in a large emergency department (ED) in New Jersey from June 1, 2016, through December 31, 2016. The purpose was to report HCV antibody and viral load results of this testing program located in a small urban/suburban area and to analyze specific characteristics associated with positive results, such as race/ethnicity and insurance status. Descriptive statistics were performed, and, using a multivariate logistic regression model, adjusted odds ratios and 95% confidence intervals were calculated. RESULTS: A total of 3046 patients were screened: 55.8% were white, and 17.9% were black; 52.1% had private insurance, 33.4% Medicare, 3.9% Medicaid. One hundred ninety-two were antibody positive (6.3%). Of 167 with HCV viral load testing results, 43% had a positive viral load. On multivariate analysis, black race and Medicaid were independently associated with a positive HCV viral load. CONCLUSIONS: HCV antibody seropositivity was above 6% and twice as high as the Centers for Disease Control and Prevention estimated prevalence in this birth cohort. These results indicate that EDs outside of large urban cities are also important sites for routine HCV screening. Other findings of interest include 43% with chronic HCV infection and the persistent association between black race and positive HCV viral load even when adjusted for insurance status.

Laboratory diagnosis of HIV in adults: a review of current methods.

Of the estimated 1.2 million people infected with human immunodeficiency virus (HIV) in the United States, 20% are unaware of their diagnosis. Improved methods of HIV testing could decrease this number, as well as identify those who have recently acquired HIV infection and are at the most critical stage of infectivity. People with acute HIV infection have demonstrated enhanced transmission of HIV in multiple epidemiologic and pathogenetic studies. More than 50 000 HIV infections occur annually in the United States, and 30%-50% have been attributed to persons with recent infection. The original HIV diagnostic testing algorithm was developed by the Centers for Disease Control and Prevention in 1989. Recently proposed alterations to the algorithm would incorporate advancements made in HIV diagnostic testing, thereby increasing sensitivity while reducing turnaround time and cost. Improved diagnosis of acute HIV, and HIV type 2 in particular, would be expected. Knowledge of the available laboratory methods for HIV diagnosis is essential in the fight against the spread of HIV.