Validation for clinical use of a novel HIV-2 plasma RNA viral load assay using the Abbott m2000 platform.

BACKGROUND: Optimal care of persons infected with human immunodeficiency virus type 2 (HIV-2) requires an accurate assessment of HIV-2 plasma viral load (VL), but no clinically approved quantitative HIV-2 RNA VL assay exists. OBJECTIVES: To validate a novel quantitative HIV-2 RNA assay for clinical and research use. STUDY DESIGN: The Abbott m2000sp/rt platform was adapted for quantification of HIV-2 RNA in plasma. Amplification targeted a region of the long terminal repeat conserved in Group A and B HIV-2. Electron microscopy-counted-HIV-2 standards, the WHO/NIBSC HIV-2 International Standard and clinical specimens (N=162) were used to determine the precision, sensitivity, specificity, linear range, accuracy, and clinical performance of the assay. RESULTS: The quantitative linear range of the HIV-2 RNA assay was 10-1,000,000 copies/mL (R(2)>0.99), with a limit of detection of 8 copies/mL (95% CI, 5-18 copies/mL). The assay did not cross-react with HIV-1, and quantification of HIV-2 RNA was not affected by the presence of >5 log(10)HIV-1 RNA copies/mL. The total standard deviation (SD) and intra- and inter-run SD were 0.095, 0.093 and 0.162, respectively, at nominal inputs of 3.7, 1.7 and 1.0 log(10)HIV-2 RNA copies/mL. The HIV-2 WHO/NIBSC International Standard (1000 IU) was shown to contain 152 RNA copies/mL (95% CI 141-163). Overall, HIV-2 RNA was quantified at ≥10 copies/mL from 86 (53%) clinical specimens (median, 2.24 log(10) copies/mL; range 10-16,870), and nine specimens (6%) had HIV-2 RNA detected at <10 copies/mL. CONCLUSIONS: We developed and validated a highly sensitive HIV-2 VL assay that is suitable for clinical and research use.

Human papillomavirus infection among sexually active young women in the United States: Implications for developing a vaccination strategy.

OBJECTIVES: Population-level data on prevalence and distribution of human papillomavirus (HPV) types in the United States are necessary to guide optimal vaccination strategies. STUDY: Urine specimens from 3262 women ages 18 to 25 in the National Longitudinal Study of Adolescent Health (Wave III) were tested and typed for HPV. Poststratification sampling weights generated nationally representative estimates. RESULTS: Overall HPV prevalence was 26.9% and as high as 14.3% among women with 1 lifetime partner but did not vary by geographic region. High-risk types were detected in 20%; approximately 10% were infected with types in current candidate vaccines. HPV infection was independently associated with mixing sex with alcohol, a black partner, >3 lifetime sex partners, being single, and illegal drug use. Having a current sex partner and receptive oral sex were inversely associated with HPV. CONCLUSION: HPV prevalence was high throughout the country, even among women with only 1 lifetime partner, suggesting early and widespread rather than targeted immunization of young women.