Search

Since 2014, the recommended laboratory testing algorithm for diagnosing human immunodeficiency virus (HIV) infection has included a supplemental HIV-1/HIV-2 differentiation test to confirm infection type on the basis of the presence of type-specific antibodies (1). Correctly identifying HIV-1 and HIV-2 infections is vital because their epidemiology and clinical management differ. To describe the percentage of diagnoses for which an HIV-1/HIV-2 differentiation test result was reported and to categorize HIV type based on laboratory test results, 2010-2017 data from CDC's National HIV Surveillance System (NHSS) were analyzed. During 2010-2017, a substantial increase in the number of HIV-1/HIV-2 differentiation test results were reported to NHSS, consistent with implementation of the HIV laboratory-based testing algorithm recommended in 2014. However, >99.9% of all HIV infections identified in the United States were categorized as HIV-1, and the number of HIV-2 diagnoses (mono-infection or dual-infection) remained extremely low (<0.03% of all HIV infections). In addition, the overall number of false positive HIV-2 test results produced by the HIV-1/HIV-2 differentiation increased. The diagnostic value of a confirmatory antibody differentiation test in a setting with sensitive and specific screening tests and few HIV-2 infections might be limited. Evaluation and consideration of other HIV tests approved by the Food and Drug Administration (FDA) that might increase efficiencies in the CDC and Association of Public Health Laboratories-recommended HIV testing algorithm are warranted., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Staphylococcal enterotoxins are a frequent cause of food poisoning. Immunologically-based assays for the detection of staphylococcal enterotoxins are commercially available, but require at minimum of 3 hours. We used staphylococcal enterotoxin B to compare two commercially available assays with a newly developed rapid immunochromatographic-based hand-held assay. The detection limit of the commercially available assays accounted for 500 pg and 100 pg enterotoxin B/ml, respectively, whereas 50 pg enterotoxin B /ml were detected within 15 min using the hand-held assay. Enterotoxin B-spiked custard served as a model to detect staphylococcal enterotoxin in food. Depending on the extraction method applied, the detection limit was in the range of 500 pg to 2500 pg/g custard for the commercially available assays and 62.5 pg/g for the hand-held assay. We conclude that the hand-held assay is widely applicable because it is sensitive, specific with regard to the tested enterotoxins, and the results can be read with the naked eye.