Infants less than 6 months of age have among the highest rates of hospitalization with COVID-19 compared to other age groups. While infants 6 months of age and younger are not eligible to be vaccinated for COVID-19, they may be protected by maternal vaccination during pregnancy.

The Yale School of Public Health’s Emerging Infections Program recently participated in a CDC study that highlights the importance of COVID vaccination to protect pregnant women and their newborns. The study examined 1,148 infants hospitalized with COVID-19 from October 2022 to April 2024.

Conversely, the percentage of infants hospitalized with COVID-19 whose mothers had been vaccinated during pregnancy decreased from 18% during October 2022–September 2023 to less than 5% during October 2023–April 2024, said Dr. Linda Niccolai, PhD, professor of public health and director of the CT EIP, which contributed Connecticut data to the study collected by Yale CT EIP Program Manager Kimberly Yousey-Hindes, MPH ’07.

Nine infants died in the hospital; all were born to mothers with no record of vaccination during pregnancy, Niccolai said. “Health care providers should be prepared to discuss the safety and effectiveness of COVID-19 vaccines with their pregnant patients, and the risks to themselves and their infants associated with not being vaccinated.”