Sudden Infant Deaths Spiked During Pandemic, Study Finds

RSV and other common infections, such as the flu, may have played a role in the increased rate of unexplained infant deaths.

Researchers have been struggling for years to understand why there was a large spike in sudden infant deaths during the COVID-19 pandemic, but the findings of a new study suggests that one factor may be a corresponding increase in other common infections that occurred around the same time.

Sudden unexpected infant death syndrome (SUIDS) is the medical term used to describe any sudden death of a child younger than one year old, regardless of the cause. These deaths often occur during sleep and may involve accidental suffocation, unsafe sleep environments, genetics and other risk factors.

While the terms are often confused, a subset of SUIDs cases are referred to as sudden infant death syndrome (SIDS), which involves instances where there is not any clear cause for the death that can be identified.

According to a report published in the journal JAMA Network Open on September 26, there was not only a spike during the pandemic in SIDS cases, but there was also an increase in SUIDS, suggesting that off-season resurgences of infections, like respiratory syncytial virus (RSV) and influenza (flu), may have played a role.

In this new study, researchers from Penn State College of Medicine, led by Dr. Catharine Paules, attempted to determine correlations between the COVID-19 pandemic and the increase in sudden infant deaths during the same period.

Paules’ team examined data from the U.S. Centers for Disease Control and Prevention (CDC) from 2018 to 2021, reviewing more than 14,000 SUIDS cases to compare rates pre-pandemic and during the pandemic.

According to the findings, the number of sudden infant deaths increased during the pandemic from 10% to 14% compared to previous years. Specifically, comparing the date range from March 2018 to December 2019, SUIDs increased by 6%.

In addition, the rate of SIDS increased by 10% during the pandemic, with the greatest increases seen in July 2021 and August 2021. SIDS makes up more than one-third of SUIDS cases.

Researchers found that the increases correlated with seasonal shifts in RSV hospitalizations. RSV infections were low during the early phases of the pandemic, due to closures and social distancing. However, as the lockdowns were lifted, an increase in RSV infections was seen along with an increase in SIDS.

The report suggests that the shift in SIDS cases during the second year of the pandemic may have been linked to the increase in RSV and similar infections, like the flu and the common cold.

However, Paules’ team indicated that more research is needed to explore different risk factors and connections to the increased risk of SUIDS, such as genetic susceptibility, environmental factors and other underlying infections.

“It may be particularly interesting to evaluate SUID rates following the rollout of several new RSV countermeasures, including maternal RSV vaccination and infant nirsevimab administration,” Dr. Paules said. “Data such as ours may help theorize plausible causal pathways and potential mitigable risk factors to further reduce the risk of SUID.”

Nirsevimab is used similarly to a vaccine in infants to protect them from RSV.

To decrease SUIDS and SIDS risks, experts recommend caregivers avoid co-sleeping with infants, practice safe sleep environments in the home, like not using soft bedding or stuffed animals in cribs, and make sure infants are up to date with immunizations.