Rotavirus jabs in NICU more beneficial than risky

New research shows limited transmission of the rotavirus vaccine strains in neonatal intensive care units (NICUs), suggesting that the benefits of vaccination outweigh earlier concerns.

In a prospective cohort of 1,238 infants (45 percent were premature, 26 percent had gastrointestinal pathology) admitted to NICU, the estimated rate of transmission to unvaccinated infants was 2.2 per 1,000 patient-days at risk (95 percent confidence interval [CI], 0.7–5.2). [Pediatrics 2024;doi:10.1542/peds.2024-067621]

A total of 226 pentavalent rotavirus vaccine (RV5) doses were administered in the cohort. Of the 3,448 stool samples collected and analysed, 2,252 were from 686 unvaccinated infants. And in this unvaccinated group of infants, only five tested positive for RV5 strain (<1 percent). No gastroenteritis symptoms were observed in transmission cases within 7 days of RV5-positive stool collection.

Five of six potential transmission events occurred within a few days of admission, indicating that some infants may have acquired RV5 before NICU entry or during admission procedures. Four of five unvaccinated infants who tested positive for RV5 shared a healthcare worker (HCW) with a source patient, and one shared a room with a recently vaccinated infant. Additionally, the RV1-vaccinated infant who tested positive for RV5 shared an HCW with a recently vaccinated infant.

“We hypothesize lapses in hand hygiene after handling the vaccine dosing tube or inadequate cleaning and disinfection of shared equipment might have contributed to these transmissions. Alternatively, RV5 strain detection in a sample from a non–RV5-vaccinated infant could reflect contamination of that stool sample,” the investigators noted.

RV5 safe to administer

“This prospective surveillance study suggests that transmission of RV5-strain rotavirus is infrequent and without detectable clinical consequence when administered to eligible NICU patients,” according to the investigators.

It has important clinical implications, given that “many NICUs avoid vaccinating patients against rotavirus until discharge due to a theoretical risk of horizontal transmission of vaccine-strain rotavirus, but many infants become age-ineligible to receive vaccine before discharge,” they continued. “We found that more than half of infants who initiated their RV5 series would have become age-ineligible by their discharge date if in-NICU vaccination had not occurred.”

The takeaway is that in-NICU administration of RV5 vaccine to stable, age-eligible infants, including premature infants, is safe, with the benefits outweighing the risks, according to the investigators. This supports the recommendations outlined in the American Academy of Pediatrics (AAP) Red Book, which advocate for the administration of rotavirus vaccine at the prescribed chronological ages, including within NICUs. [American Academy of Pediatrics. Rotavirus infections. In: Kimberlin DW, Banerjee R, Barnett ED, Lynfield R, Sawyer MH, eds. Red Book: 2024 Report of the Committee on Infectious Diseases. American Academy of Pediatrics; 2024:730–735]

“While this study was conducted in a level 4 referral NICU, our combination of both single patient rooms as well as open pods supports its generalizability to a variety of NICUs of different layouts and sizes," said senior investigator Dr Kathleen Gibbs, Medical Director of Quality Improvement and Patient Safety of the NICU at Children's Hospital of Philadelphia in Philadelphia, Pennsylvania, US.