Rise in cases of parechovirus in children

Aug. 18, 2022

According to a release from Vanderbilt University Medical Center (VUMC), physicians at Monroe Carell Jr. Children’s Hospital at Vanderbilt recently reported an unusually high number of patients infected with a virus called parechovirus.

A cluster of 23 infants was diagnosed in a six-week span at the hospital.

What makes this unusual is that in the previous three years, including those spanning the COVID-19 pandemic, only seven cases of parechovirus were reported.

“While this is not a new virus, it can cause severe illness, including central nervous system infections, in infants younger than 3 months old,” said Ritu Banerjee, MD, PhD, professor of Pediatrics and Infectious Diseases.

“What was surprising was the number of cases detected in babies in a short period of time.

“It was important to publish the case series to raise awareness among providers that this virus was circulating so patients could be appropriately evaluated.”

Parechovirus infections are common in childhood and typically present with nonspecific symptoms including upper respiratory infections, gastroenteritis, fever, rash and sometimes meningitis.

The team’s findings were reported in Morbidity and Mortality Weekly Report (MMWR), a publication of the Center for Disease Control, which also issued a health alert to encourage clinicians to consider testing for the virus. The alert cautioned that a specific strain of the virus, called PeV-A3, was circulating in multiple states.

Banerjee, senior author Romney Humphries, B.Sc., PhD, professor of Pathology, Microbiology and Immunology along with Lili Tao, MD, PhD, a clinical fellow in the Department of Pathology, Microbiology and Immunology, believe that the surge in cases may be linked to easing of social restrictions for the COVID-19 pandemic and the resulting increase in social activities.

“We don’t fully understand why we saw this uptick, but perhaps it can be attributed to relaxation of COVID-19 isolation measures,” said Tao, the first author on the report.

“Much like we saw with the flu and RSV, these viruses were not circulating as much during the height of the pandemic.

“This virus is transmitted via respiratory droplets (sneezing and coughing) and fecal-oral contact. It’s important that clinicians be aware of parechovirus circulation and order tests that are able to detect this virus. This can help better manage and monitor patients.”

In children between 6 months and 5 years old, the virus usually causes upper respiratory infections and fever. But in infants younger than 3 months, the virus can cause seizures, sepsis-like illness and brain inflammation.

There is no specific treatment for parechovirus, but the team said a lumbar puncture is part of routine care when an infant comes in very ill. A key signal of severe infection is inflammation in the spinal fluid. But in these cases, inflammation was not present.

“We are detecting the virus. We are seeing the disease, but there is not necessarily a lot of inflammation,” said Banerjee. “The take home message for clinicians — the absence of CSF inflammation does not rule out parechovirus infection in infants.

“Patients need supportive care and those with more severe disease need appropriate follow-up care after discharge to ensure neurodevelopment is on track.”

VUMC release