In the JournalsPerspective

RSV burden among young children greater than previously thought

Photo of Joana Lively
Joana Lively

New estimates show that the burden of respiratory syncytial virus, or RSV, among children aged younger than 2 years in the outpatient setting is higher than previously reported, and children aged younger than 6 months are particularly high risk.

Joana Lively, MPH, an epidemiologist in the CDC’s Division of Viral Disease, and colleagues used previously unpublished data from the New Vaccine Surveillance Network (NVSN) to estimate rates of RSV-associated ED and pediatric practice visits among children aged younger than 24 months between 2004 and 2009. The analysis included 3,339 children from Nashville, Tennessee; Rochester, New York; and Cincinnati, Ohio. Among them, 1,532 were tested for RSV in EDs and 1,724 were tested in pediatric practices, with 21% and 18% testing positive for RSV, respectively.

Lively and colleagues said the average annual RSV infection rates among children aged younger than 2 years was 59.6 (95% CI, 50.9-68.3) and 205.7 (95% CI, 169.5-241.9) per 1,000 children for ED and pediatric practice visits, respectively.

In the ED, rates of RSV increased after birth, peaking at a rate of 116 (95% CI, 99.3-132.7) per 1,000 children at 4 months of age. In pediatric practices, the peak rate was 289.2 (95% CI, 241.1-337.2) per 1,000 children at 5 months of age.

The researchers said the new estimates for children aged younger than 24 months in ED and primary care settings suggest that the RSV burden in this age group might be approximately 1.5-fold higher than what they had previously reported.

“The study findings reiterate the importance of RSV as a cause of outpatient visits for children under 2 years of age,” Lively told Infectious Diseases in Children. “It particularly highlights the large burden in infants under 6 months of age and may help guide the potential use of novel maternal vaccines and RSV-specific antibody products that are under development.” – by Bruce Thiel

Disclosures: The authors report no relevant financial disclosures.

Photo of Joana Lively
Joana Lively

New estimates show that the burden of respiratory syncytial virus, or RSV, among children aged younger than 2 years in the outpatient setting is higher than previously reported, and children aged younger than 6 months are particularly high risk.

Joana Lively, MPH, an epidemiologist in the CDC’s Division of Viral Disease, and colleagues used previously unpublished data from the New Vaccine Surveillance Network (NVSN) to estimate rates of RSV-associated ED and pediatric practice visits among children aged younger than 24 months between 2004 and 2009. The analysis included 3,339 children from Nashville, Tennessee; Rochester, New York; and Cincinnati, Ohio. Among them, 1,532 were tested for RSV in EDs and 1,724 were tested in pediatric practices, with 21% and 18% testing positive for RSV, respectively.

Lively and colleagues said the average annual RSV infection rates among children aged younger than 2 years was 59.6 (95% CI, 50.9-68.3) and 205.7 (95% CI, 169.5-241.9) per 1,000 children for ED and pediatric practice visits, respectively.

In the ED, rates of RSV increased after birth, peaking at a rate of 116 (95% CI, 99.3-132.7) per 1,000 children at 4 months of age. In pediatric practices, the peak rate was 289.2 (95% CI, 241.1-337.2) per 1,000 children at 5 months of age.

The researchers said the new estimates for children aged younger than 24 months in ED and primary care settings suggest that the RSV burden in this age group might be approximately 1.5-fold higher than what they had previously reported.

“The study findings reiterate the importance of RSV as a cause of outpatient visits for children under 2 years of age,” Lively told Infectious Diseases in Children. “It particularly highlights the large burden in infants under 6 months of age and may help guide the potential use of novel maternal vaccines and RSV-specific antibody products that are under development.” – by Bruce Thiel

Disclosures: The authors report no relevant financial disclosures.

    Perspective

    Photo of Octavio Ramilo 
    Octavio Ramilo
    Photo of Asuncion Mejias 
    Asuncion Mejias

    In this article, investigators from the NVSN provided a detailed description of the rates of RSV infection in the outpatient setting by month of age during the first 2 years of life, as observed in both the ED and in pediatric practices.

    This information is relevant because it has important practical implications. To date, most studies on the burden of RSV disease have focused on inpatients. These data, however, confirmed that the burden of the disease is much higher in the outpatient setting and the disease peak occurs at an older age compared with the peak of the disease in infants requiring hospitalization. As new modalities to prevent RSV infection using different vaccination strategies and monoclonal antibodies are being developed, it is critical that those clinical trials also evaluate the impact of those interventions in outpatients across different age groups. Furthermore, the present study suggests that, in addition to preventive strategies, there is a potential opportunity for therapeutic interventions against RSV infections using antiviral agents in the pediatric population. 

    Octavio Ramilo, MD

    Chief, division of infectious diseases

    Nationwide Children’s Hospital

    Asuncion Mejias, MD, PhD

    Associate professor of pediatrics, division of infectious diseases

    Nationwide Children’s Hospital and The Ohio State University

    Disclosures: Ramilo and Mejias report that they have received research grants from Janssen, NIH and the Bill & Melinda Gates Foundation. Ramilo also reports honoraria for participation in advisory boards from Sanofi and Medimmune.

    Perspective
    David I. Bernstein

    David I. Bernstein

    This timely article, derived from data collected from the NVSN group, highlights the high burden of disease due to RSV infections during the first months of life. Compared with their previous estimates for young children, the results reported here suggest that the RSV burden might be approximately 1.5-fold higher than that previously reported. This increased estimate further reinforces the need to develop prevention strategies for RSV. Fortunately, efforts to develop RSV vaccines and other prevention strategies have increased, but those efforts must be able to impact the early onset of disease.

    References:

    Gerretsen HE, et al. J Infect. 2017;doi:10.1016/S0163-4453(17)30205-0.

    Graham BS, et al. Curr Opin Virol. 2017;doi:10.1016/j.coviro.2017.03.012.

    Hall CB, et al. N Engl J Med. 2009;doi:10.1056/NEJMoa0804877.

    Simões EAF, et al. Infect Dis Ther. 2018;doi:10.1007/s40121-018-0188-z.

    • David I. Bernstein, MD, MS
    • Director, division of infectious diseases
      Cincinnati Children’s Hospital Medical Center

    Disclosures: Bernstein reports no relevant financial disclosures.