SDI and MedImmune Announce Study on Geographically Specific, Seasonal RSV Disease Outbreak Data

SDI, a leading disease surveillance and healthcare informatics organization, in partnership with biotechnology company MedImmune, has announced the publication of a study on the variances of the respiratory syncytial virus (RSV) season between major U.S. metropolitan areas. The study is published in the December issue of the Pediatric Infectious Disease Journal.

RSV is the most common cause of respiratory infections in infants and young children and is the leading cause of hospitalization in children less than 24 months of age (1-3). Each year, an estimated 125,000 infants in the United States are hospitalized with severe RSV infections. Those at the greatest risk for severe disease or death include high-risk premature infants and those with compromised respiratory, cardiac, or immune systems (4, 5). The virus is transmitted from person to person through the air and from contact with infected surfaces, and it predominantly circulates during fall and winter months in the Northern Hemisphere.

The published study findings demonstrated that there is significant variability in the onset and duration of RSV activity between metropolitan areas located within the same region. For example, in the three-year study, greater than 73 percent of all the measured metropolitan areas revealed at least one week of significant RSV activity outside of the traditional American Academy of Pediatrics (AAP)-defined season for RSV activity (or outbreaks) in their region, which is typically November through March. In addition, the study found that the Southern region experienced the longest duration and earliest conclusion of RSV activity while the Midwest region exhibited the latest season commencement and peak. Portions of Florida demonstrated year-round RSV outbreaks (6, 7).

Furthermore, Las Vegas, Portland and Salt Lake City had longer RSV seasons than other areas in the region. Investigators hypothesized that the expanded season could be due to the large influx of visitors from international tourism and business conventions during peak travel months (8). Additionally, Ohio, Illinois and Missouri had metropolitan areas that experienced an RSV season that was at least four weeks longer than the average for the region.

The study was conducted using MedImmune's RSV surveillance program (RSV Alert®), which is based on SDI's disease surveillance database, technology and analytics capabilities, to help physicians correctly time RSV care for high-risk infants in their respective metropolitan cities and regions.

"RSV is a serious respiratory disease that can have significant effects on otherwise healthy infants. We are committed to developing therapies that reduce the prevalence and impact of these types of infectious diseases and improve the overall health of these patients," said Dr. Frank Malinoski, MD, PhD, senior vice president of medical and scientific affairs for MedImmune, and one of the study authors.

“SDI supplies the industry's largest database of disease surveillance data to the RSV Alert program, providing real-time data at a city/local level throughout the nation, which is critical for delivering the information needed for improved clinical decision-making regarding RSV management,” said Laurel Edelman, SDI vice president of clinical accounts, who is also a study author. “Until now, clinicians had to estimate when RSV outbreaks would occur locally, which varied each season and within the region itself, risking the health of thousands of infants due to lack of detailed data for their specific regions.”

Added Edelman, “This study has revealed considerable variation in the onset and duration of the RSV season by region, including active RSV activity outside of the traditional window for RSV care (or as defined by the AAP), which is November through March. This data has tremendous potential to assist clinicians as they manage the health of high-risk premature infants and other high-risk patients in their community.”

SDI has committed resources and expertise on an ongoing basis to enhance RSV prevention efforts. Through a data-sharing agreement with SDI, the Centers for Disease Control and Prevention (CDC) uses SDI data to report RSV activity nationwide through the National Respiratory and Enteric Virus Surveillance System (NREVSS). Expanding upon the NREVSS surveillance efforts, the real-time RSV surveillance implemented during this study analyzed data at the metropolitan city level, enabling researchers to distinguish local geographical and temporal seasonal trends, which leads to more timely and effective care of high-risk infants.

In addition to RSV, SDI Clinical Operations conducts clinical surveillance programs for a number of other diseases and conditions including colds, respiratory illness, influenza and allergies based on de-identified, aggregated data collected weekly from hospitals, laboratories, physician offices, health centers, pharmacies, blood banks and public health offices around the country.


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Source: SDI