Old and New Lessons in respiratory viral transmission in children

Reviewed by Emily Thorell, MD MSCI, University of Utah Health and Zachary Willis, MD MPH, University of North Carolina School of Medicine 

Investigators from a large freestanding children’s hospital analyzed cases of healthcare-acquired viral infections (HA-VI) to determine risk factors for HA-VI. The cases were mostly respiratory, with a few gastrointestinal infections. For 64 enrolled HA-VI cases, they identified and enrolled a control patient matched by age, admission date, and unit. They conducted structured interviews with parents of enrolled patients to identify risk factors such as possible exposures to ill contacts, specifically asking about contact with potentially sick visitors, other patients, or healthcare workers. They found that 25% of cases vs 9.3% of controls had reported contact with a sick visitor, the only statistically significant difference between the groups. These exposures occurred despite robust symptom screening for visitors. While this study was conducted prior to the SARS-CoV-2 pandemic, these findings are perhaps even more helpful as healthcare facilities face repeated, nonseasonal waves of both COVID-19 and previously common respiratory viruses.

And in the era of COVID (pre-Delta variant), a nicely done population-based cohort study out of Ontario, Canada looked at secondary household transmission of SARS-CoV-2 when an index case was <18 years old. They found that 27% of households experienced secondary transmission. Children aged 0 to 3 years had the highest odds of transmitting SARS-CoV-2 to household contacts compared with children aged 14 to 17 years (odds ratio, 1.43; 95% CI, 1.17-1.75) leading the authors to conclude that parents with the youngest infected children may want to take more infection prevention measures such as masking at home. The simultaneously published editorial reminded us all of a great sentinel study by Hall et al about RSV transmission and how we know that those that need to be “cuddled” are often better transmitters of respiratory virus to their caregivers. As we know parents will appropriately cuddle their sick children and the siblings will have a hard time staying away, it is important to make sure that parents and eligible siblings are vaccinated against Sars-CoV-2 as a more effective intervention to preventing secondary household transmission. This is even more important now that the predominant strain is the Delta variant!

Both studies are a good reminder that parents will parent. Cuddling will happen when kids are sick (and when they are not) and we need to consider this in the hospital and at home when it comes to viral transmission to support the parents in the safest way possible.


  • Hanley S, Odeniyi F, Feemster K, Coffin SE, Sammons JS. Epidemiology and Risk Factors for Healthcare-Associated Viral Infections in Children. Journal of the Pediatric Infectious Diseases Society. 2021;(piab015). doi:10.1093/jpids/piab015
  • Paul LA, Daneman N, Schwartz KL, et al. Association of Age and Pediatric Household Transmission of SARS-CoV-2 Infection. JAMA Pediatr. Published online August 16, 2021. doi:10.1001/jamapediatrics.2021.2770
  • Coffin SE, Rubin D. Yes, Children Can Transmit COVID, but We Need Not Fear. JAMA Pediatr. Published online August 16, 2021. doi:10.1001/jamapediatrics.2021.2767
We use cookies to help improve your experience