Laboratory testing trends for respiratory syncytial virus, 2007-2011

Background: Antigen detection tests have been the most common diagnostic assay used to detect and diagnose respiratory syncytial virus (RSV). The utility and increased sensitivity of polymerase chain reaction (PCR) tests have been reported; however, their use in US hospital laboratories is not well characterized. Objective: To describe changes in RSV test types used by US hospital-affiliated laboratories, focusing on PCR testing prevalence. Study design: Data were collected from 480 to 666 laboratories each RSV season (2007-2008 through 2010-2011) across 50 states, the District of Columbia, and Puerto Rico. A descriptive analysis was conducted using this convenience sample of RSV tests conducted from November to April each season. Total numbers and types of RSV tests performed were reported weekly and weekly proportions by test type were calculated. Kendall tau rank correlation was used to quantify associations between time and proportions of each test type. Results: PCR tests accounted for 2%, 3%, 16%, and 21% of weekly tests (total range, 381,068-481,654 over 4 seasons) conducted each season from 2007 to 2011, respectively. The proportion of laboratories reporting >= 1 PCR tests was 4%, 5%, 10%, and 16%, respectively. Decreases in antigen testing and viral culture were similarly observed. Conclusions: Although antigen detection was the predominant test type reported in the sample of US hospital laboratories for RSV testing, PCR use increased to >20% of tests reported. These results demonstrate the increasing contribution of PCR to RSV surveillance. RSV surveillance systems relying solely on antigen detection results will not capture an increasing proportion of RSV test results. (C) 2013 The Authors. Published by Elsevier B. V. All rights reserved.