COVID-19 Care
Clarissa Chan, PharmD
A December 2021 simulation modeling study of 19.45 million people published in JAMA Network Open found that when introducing respiratory syncytial virus (RSV) from external sources to mimic the relaxation of COVID-19 pandemic precautions in the United States, hospitalization rates were expected to increase between the spring and summer of 2021. Modeling also found that higher infection rates from external RSV sources predicted more severe spring and summer epidemics.
Study authors Daniel M. Weinberger, PhD, and Zhe Zheng, MBBS, PhD candidate, both from the Yale School of Public Health, collaborated to answer the following questions, which may help to clarify what pharmacists should know about unusual RSV outbreaks the COVID-19 pandemic may trigger in the near future.
Why do you predict that the COVID-19 pandemic will precipitate RSV epidemics?
“We were concerned that there was an unusually large number of children who had not been exposed to RSV and did not have immunity, which could potentially trigger an unusually large RSV epidemic,” said Zheng. “We wanted to understand the potential implications of this disruption for the intensity, timing, and age distribution of subsequent epidemics once RSV did re-emerge.”
Many common viruses, like influenza and RSV, disappeared as nonpharmaceutical interventions like masking were put in place in response to the COVID-19 pandemic. By March 2021, most regions in the world had not seen RSV for more than a year, with the exception of an unusual out-of-season outbreak in Australia. Normally, RSV is very common in the general population, and people are frequently exposed, building up natural immunity.
Why is this a cause for concern?
Understanding the possible intensity of re-emergent RSV epidemics and the age distribution of infections can inform who should receive RSV prophylaxis and help hospital capacity management. Since RSV is the leading cause of lower respiratory tract illness in young children, a large RSV outbreak may swamp the pediatric wards and PICUs.
In the summer of 2021, children’s hospitals in the Netherlands had to transfer several seriously ill pediatric patients to other countries due to full PICUs. Older children were also hospitalized because of RSV infection in 2021, as anticipated by the study.
What can health care professionals do to monitor these trends?
Out-of-season RSV epidemics are possible. Health care professionals should consider performing RSV diagnostic testing for young children routinely this year, even when it is not a typical RSV season, to pick up the early resurgent signals. The situation needs to be monitored for possible out-of-season administration of palivizumab or even administering it to high-risk infants and children who are one to two years old.
What other factors cause the RSV epidemics?
The exact drivers that cause out-of-season surges of RSV are not completely understood. School reopening and temperature may be associated with the risk for RSV rebound, as shown in a March 2022 study published in The Journal of Infectious Diseases.
“We also did an analysis comparing the relative timing of the resurgent RSV epidemics with a typical winter season,” said Zheng. The 2022 short communication in Influenza and Other Respiratory Viruses “shows that RSV epidemics in summer 2021 follow the same spatial transmission patterns as a typical RSV season, moving from Florida to the northern and western coast of the U.S.”
What still needs to be investigated?
We still do not know the level of waning maternal immunity to RSV. The waning of maternal immunity may increase the risk of RSV infection in neonates who are the most vulnerable population. It will also be interesting to know the global geographic source of RSV infections.
How should pharmacists educate other health care providers and patients based on the study findings?
As COVID-19 restrictions continue to be lifted, many young children will be exposed to RSV for the first time. Some may develop severe RSV. This may occur at unusual times this year and when high-risk infants are not typically using prophylaxis against RSV. Children under 5 years old have a higher risk of developing RSV lower respiratory tract illness and may require inpatient treatment this coming year compared with previous RSV seasons.
Therefore, RSV needs to be monitored for possible out-of-season administration of palivizumab. Pharmacists can help patients manage fever and pain with OTC fever reducers and pain relievers, like acetaminophen or ibuprofen. Also, be cautious about suggesting antibiotics to parents who are seeking help for their young children who show respiratory infection symptoms; it is important to remember that RSV is caused by a viral infection; antibiotics will not treat the condition. ■