Many health systems are now reporting significant increases in parechovirus infections in infants after the outbreak in children’s hospitals disappeared during the COVID-19 pandemic.
A new report released by the Centers for Disease Control and Prevention documents a spike in cases at one Tennessee medical center that has hospitalized 29 cases so far this year, including 23 infants in a six-week period.
This represents an increase compared to previous years: in 2018, only 19 cases were detected in five months.
While parechoviruses usually infect children and cause only mild symptoms in many children, the virus can cause severe illness when it infects infants under three months of age. Some develop sepsis-like symptoms or central nervous system infections. It also increases the risk of long-term developmental problems.
So far, at least 21 of the babies have recovered. One child is expected to have “severe developmental delays” after “sustained seizures”.
The findings, from doctors at Vanderbilt University Medical Center and the Tennessee Department of Health, were published Thursday in the CDC’s Morbidity and Mortality Weekly Report.
The most common symptoms among infants enrolled in the study were fever, irritability, and poor appetite.
This follows a health alert issued by the CDC earlier this month that warned of several states reporting parechovirus infections in newborns and young infants. It comes as pediatric infectious disease doctors across the country are investigating the outbreak.
CBS affiliate WFSB-TV reported earlier this month on a Connecticut family grieving the death of an infant who contracted an infection.
Is there really an increase in cases? “This is not normal”
“Some doctors in the community are saying in our infection forums, ‘hey, we’re seeing more of these cases, are you seeing more of this?’ Well, we, several facilities around the country, we’re seeing a lot, and it’s not what we’re used to,” said Dr. Tomatis Souverbielle of Ohio National Children’s Hospital.
Souverbielle co-authored a study published last year that looked for parechovirus in several parts of the body, including the cerebrospinal fluid and blood of infants. They have seen about 20 cases so far this year, mostly starting in June.
Many other health systems have recently expanded testing for parechovirus infections, which is expensive and performed by multiple laboratories. There is also no systematic national surveillance of parechovirus in the United States, the CDC says.
“Some doctors were arguing that maybe it’s because we’re screening more and we don’t know. But I think we already knew, we were screening before, and it’s not normal,” Suwerbiel said.
Parechoviruses are believed to be most prevalent in the summer and fall. Souverbielle Hospital observed a similar trend, but also reported cases in every month of the year.
Most children may experience little or no parechovirus infection by kindergarten, the CDC says, and it can be spread through feces for weeks and months through respiratory symptoms.
“They are more common than enteroviruses, which are well known to pediatricians as the cause of summer meningitis in young infants. Parechoviruses are the most common and important viral pathogens affecting the central nervous system of infants,” said Dr. Mary Ann Jackson, dean of the University of Missouri-Kansas City School of Medicine.
Are we seeing more parechovirus due to COVID-19?
Jackson’s Hospital – Children’s Mercy Hospital – Kansas City is one of the few hospitals that has been routinely testing and studying young infants with possible symptoms for several years.
Jackson shared surveillance data that tracked the virus’s unique annual spread since 2006, which reached 62 hospitalizations in 2018.
But this scheme was disrupted in 2020 when the country was hit by the COVID-19 pandemic, and for months they expected to see a wave of infections.
Parechoviruses are now circulating again and can infect young children more quickly than in previous years. Jackson’s hospital has seen 25 this year.
“Certainly in the next two to four weeks, I expect we’ll see more cases, especially if our numbers continue to go down for COVID and parechoviruses continue to increase, August is a big time for this virus,” Jackson said.
Suwerbiel said scientists are exploring different theories as to why infection rates may be higher this year after the COVID-19 pandemic. The easing of restrictions due to the pandemic may have led to a greater spread of the parechovirus, as families began mixing again.
“There’s also a theory that because kids haven’t been exposed to it in the last few years, now they’re more exposed and more exposed to it,” Suwerbel said.
How to treat parechovirus disease in babies?
According to the CDC, all cases of parechovirus investigated by the agency to date have been of a specific strain of the virus known as PeV-A3. This type of virus, which accounts for the majority of parechoviruses “typed” in some previous studies, is also often associated with severe cases.
Diagnosing an infant with parechovirus can help doctors manage infections, including avoiding unnecessary testing and stopping antibiotics started before a bacterial infection can be ruled out.
However, there are no specific antiviral drugs approved to treat these infections.
“There’s really no treatment. Babies get better on their own. All the treatment is supportive. So it’s IV fluids, it’s temperature control, it’s seizure management for babies who have seizures,” he said. Jackson said.
Giving parents information about their baby’s diagnosis also helps them monitor their child’s development in the coming years, Jackson said.
A growing body of research shows that the small number of children who survive the disease in infancy may experience neurodevelopmental delays as they grow up, requiring early intervention by their schools and parents.
These developmental problems aren’t always predictive of how severe the original illness was, Jackson said.
“We know that affected babies are sometimes malformed, but sometimes they’re completely normal. And some of the babies who weren’t as affected by the initial infection seemed to develop completely normally.” Jackson said.