TEMPORAL EFFICACY AND STERILITY TESTING OF POVIDONE-IODINE FROM AN OPEN BOTTLE.

PURPOSE: To investigate the temporal efficacy and sterility of povidone-iodine (PI) against bacteria associated with postinjection endophthalmitis in an in vitro study. METHODS: A single PI bottle was opened and tested for sterility and antibacterial efficacy. Povidone-iodine from the open bottle was inoculated onto a blood agar plate and evaluated for growth 24 hours later to test sterility; this was repeated for five consecutive days. To test for antibacterial efficacy, PI was instilled onto the surface of plates of Staphylococcus , Streptococcus , Enterococcus , Pseudomonas , and Haemophilus species. The plates were then evaluated 24 hours later for a clear zone of inhibition (i.e., no growth) where the PI was placed. This process was repeated for five consecutive days. RESULTS: Sterility testing showed no growth of organisms on the blood agar plates for each of the five days of testing. For antibacterial efficacy testing, zones of inhibition of growth were seen on each plate of bacterial colonies only where PI was placed, for each of the five days of testing. CONCLUSION: In this study, PI from an open bottle maintained its sterility and antibacterial efficacy for five days. These data could help support repeated use of the same bottle, reducing waste and costs for retina practices.

Multicenter Evaluation of the Cepheid Xpert Xpress SARS-CoV-2/Flu/RSV Test.

With the approach of respiratory virus season in the Northern Hemisphere, clinical microbiology and public health laboratories will need rapid diagnostic assays to distinguish severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from influenza virus and respiratory syncytial virus (RSV) infections for diagnosis and surveillance. In this study, the clinical performance of the Xpert Xpress SARS-CoV-2/Flu/RSV test (Cepheid, Sunnyvale, CA, USA) for nasopharyngeal swab specimens was evaluated in four centers: Johns Hopkins Medical Microbiology Laboratory, Northwell Health Laboratories, NYC Public Health Laboratory, and Los Angeles County/University of Southern California (LAC+USC) Medical Center. A total of 319 nasopharyngeal swab specimens, positive for SARS-CoV-2 (n = 75), influenza A virus (n = 65), influenza B virus (n = 50), or RSV (n = 38) or negative (n = 91) by the standard-of-care nucleic acid amplification tests at each site, were tested using the Cepheid panel test. The overall positive percent agreement for the SARS-CoV-2 target was 98.7% (n = 74/75), and the negative agreement was 100% (n = 91), with all other analytes showing 100% total agreement (n = 153). Standard-of-care tests to which the Cepheid panel was compared included the Cepheid Xpert Xpress SARS-CoV-2, Cepheid Xpert Xpress Flu/RSV, GenMark ePlex respiratory panel, BioFire respiratory panel 2.1 and v1.7, DiaSorin Simplexa COVID-19 Direct, and Hologic Panther Fusion SARS-CoV-2 assays. The Xpert Xpress SARS-CoV-2/Flu/RSV test showed high sensitivity and accuracy for all analytes included in the test. This test will provide a valuable clinical diagnostic and public health solution for detecting and differentiating SARS-CoV-2, influenza A and B virus, and RSV infections during the current respiratory virus season.