Background: Respiratory syncytial virus (RSV) circulates in most areas of the US primarily during November to April. Florida, particularly the southeast area, has exhibited a unique pattern of RSV circulation with earlier onset and longer duration. Similarly prolonged RSV circulation has been observed in Puerto Rico. RSV circulation was assessed in Florida, Puerto Rico, and the rest of the US using the National Respiratory and Enteric Viruses Surveillance System (NREVSS). Additionally, RSV occurrence was examined for association with weather data that included temperature, humidity ad precipitation variables, using data from Weather Underground and National Oceanic and Atmospheric Administration (NOAA).
Methods: NREVSS weekly data was submitted from laboratories in the 50 states (2011-2013) and Puerto Rico (2011-2013). The number and percentage of specimens RSV-positive by antigen detection were used for consistency across geographic areas and years. RSV onset (first of 2 consecutive weeks with >10% RSV-positives) and offset (last of 2 consecutive weeks with <10% RSV-positives) defined RSV periods of increased seasonal epidemic activity, which were compared between southeast Florida, the rest of Florida, Puerto Rico, and the rest of the US. Weather stations were used to identify meteorological data for Southeast Florida region and Puerto Rico region. In order to assess whether the percent positive of RSV peak, which indicates the severity of the RSV season was associated with the peaks in temperature, humidity and precipitation, Poisson regression analysis was performed.
Results: From 2011-2013, 517 laboratories (including 3 in Puerto Rico; 11 in southeast Florida) reported ~740,000 RSV antigen tests to NREVSS, of which 13% were RSV-positive. Puerto Rico remained >10% RSV-positive for all months and closely paralleled the timing and shape of the RSV curve in southeast Florida, which had RSV onset during June-July compared to November for the rest of the US. RSV activity peaked earlier for southeast Florida and Puerto Rico (September-October), followed by the rest of Florida (November-December), and then the rest of the US (January-February). Poisson analysis reveled a positive correlation between RSV peaks and both temperature and humidity in the Puerto Rico region and a positive correlation between RSV peaks and temperature and precipitation in the Southeast Florida region.
Conclusions: RSV increased activity occurred months earlier in southeast Florida and Puerto Rico compared to the rest of the US, suggesting that factors uniquely common to southeast Florida and Puerto Rico might contribute to their seasonality, which has implications for timing of RSV interventions. Temperature and humidity were significantly associated with the peaks in RSV in the regions with tropical weather.
Table of Contents
Table of Contents
Introduction 1 - 3
Methods 4 - 7
Results 8 -15
Conclusions 16 - 1
References 19 - 22
About this Master's Thesis
|Committee Chair / Thesis Advisor|
|Differential RSV seasonal patterns and meteorological factors in Florida, Puerto Rico and other US regions ()||2018-08-28||