Background The Centers for Disease Control and Prevention recently recommended the expansion of human immunodeficiency virus (HIV) antibody testing. However, antibody tests have longer “window periods” after HIV acquisition than do nucleic acid amplification tests (NAATs). Methods Public Health–Seattle & King County offered HIV antibody testing to men who have sex with men (MSM) using the OraQuick Advance Rapid HIV-1/2 Antibody Test (OraQuick; OraSure Technologies) on oral fluid or finger-stick blood specimens or using a first- or second-generation enzyme immunoassay. The enzyme immunoassay was also used to confirm reactive rapid test results and to screen specimens from OraQuick-negative MSM prior to pooling for HIV NAAT. Serum specimens obtained from subsets of HIV-infected persons were retrospectively evaluated by use of other HIV tests, including a fourth-generation antigen-antibody combination assay. Results From September 2003 through June 2008, a total of 328 (2.3%) of 14,005 specimens were HIV antibody positive, and 36 (0.3%) of 13,677 antibody-negative specimens were NAAT positive (indicating acute HIV infection). Among 6811 specimens obtained from MSM who were initially screened by rapid testing, OraQuick detected only 153 (91%) of 169 antibody-positive MSM and 80% of the 192 HIV-infected MSM detected by the HIV NAAT program. HIV was detected in serum samples obtained from 15 of 16 MSM with acute HIV infection that were retrospectively tested using the antigen-antibody combination assay. Conclusions OraQuick may be less sensitive than enzyme immunoassays during early HIV infection. NAAT should be integrated into HIV testing programs that serve populations that undergo frequent testing and that have high rates of HIV acquisition, particularly if rapid HIV antibody testing is employed. Antigen-antibody combination assays may be a reasonably sensitive alternative to HIV NAAT.

Objective: We have reexamined hepatitis B virus subtypes to determine the role of specific HBsAg amino acids in serologic reactivity because of problematic genotype/subtype associations seen in a set of geographically diverse serum specimens. Methods: We obtained DNA sequences for 491 HBsAg-positive specimens from geographically distinct locations, determined their genotypes through phylogenetic analysis, and subtyped the specimens using an algorithm derived from published data on the molecular basis of HBsAg subtype reactivity. Problematic samples were subtyped serologically to resolve conflicts based on the amino acid sequence alone. Results: Three isolates were found to have unusual genotype/subtype associations. Examination of the isolates’ amino acid sequences suggested amino acid positions 122, 127, 140, 159 and 160 can be used to determine subtype reactivity from HBsAg amino acid sequences, while position 134, previously thought to play a role, is no longer important. Conclusions: This re-examination of hepatitis B virus subtypes shows the involvement of amino acid positions 122, 127, 140, 159 and 160 in HBsAg reactivity. While d, y, and r reactivities are controlled by single amino acid changes, w reactivity is determined by positions 122, 127, 140, and 159.

HIV-RNA testing may identify individuals with primary HIV infection. Men who have sex with men (MSM) having HIV testing through Public Health, Seattle and King County were screened for primary infection through pooled RNA testing. Eighty-one out of 3525 specimens (2.3%) had detectable antibody and RNA, and seven out of 3439 antibody-negative specimens (0.2%) had HIV RNA. Targeted screening for primary infection through pooled RNA testing in MSM is a useful addition to HIV case finding.

Clinicians should consider selectively using a higher index value to define Focus ELISA HSV-2 positivity based on either HSV-1 serostatus or clinical circumstances.

Background Point-of-care (POC) rapid HIV tests have sensitivity during the “window period” comparable only to earliest generation EIAs. To date, it is unclear whether any POC test performs significantly better than others. Objective Compare abilities of POC tests to detect early infection in real time. Study Design Men who have sex with men (MSM) were recruited into a prospective, cross-sectional study at two HIV testing sites and a research clinic. Procedures compared four POC tests: one performed on oral fluids and three on fingerstick whole blood specimens. Specimens from participants with negative POC results were tested by EIA and pooled nucleic acid amplification testing (NAAT). McNemar’s exact tests compared numbers of HIV-infected participants detected. Results Between February 2010 and May 2013, 104 men tested HIV-positive during 2479 visits. Eighty-two participants had concordant reactive POC results, 3 participants had concordant non-reactive POC tests but reactive EIAs, and 8 participants had acute infection. Of 12 participants with discordant POC results, OraQuick ADVANCE Rapid HIV-1/2 Antibody Test performed on oral fluids identified fewer infections than OraQuick performed on fingerstick (p=.005), Uni-Gold Recombigen HIV Test (p=.01), and Determine HIV-1/2 Ag/Ab Combo (p=.005). Conclusions These data confirm that oral fluid POC testing detects fewer infections than other methods and is best reserved for circumstances precluding fingerstick or venipuncture. Regardless of specimen type, POC tests failed to identify many HIV-infected MSM in Seattle. In populations with high HIV incidence, the currently approved POC antibody tests are inadequate unless supplemented with p24 antigen tests or NAAT.