CDC: US infants are falling sick with a life-threatening virus that triggers fever, delirium, seizures, and sepsis

• The CDC is warning that parechovirus are spreading in "multiple states."
• While older kids typically suffer mild respiratory infections, the viruses can be life-threatening for babies.

Federal health officials in the US are warning doctors and parents that a dangerous virus is spreading across the US causing fevers, seizures, confusion and other "sepsis-like" issues that can be life-threatening for young infants.

The Centers for Disease Control and Prevention (CDC) said Tuesday that parechovirus is currently circulating in "multiple" US states. So far, the CDC has only collected positive samples of PeV-A3, which is the specific type of parechovirus that is most often associated with severe disease. At least one newborn is dead in Connecticut.

Baby Ronan was less than two weeks old when his mom starting noticing he was becoming "very angry," and "crying a lot," WTNH New Haven reported.

His chest turned red, and then his face too, and at 14 days old he was admitted to the hospital, where he started having seizures. At 34 days old, the child died.

There is no known treatment for parechovirus. Older children who get infected may "only have mild illness," like a cold, while others may remain completely asymptomatic during their infection, and feel nothing at all, the CDC says.

CDC is telling doctors to be alert for signs of parechovirus

The CDC is urging pediatricians across the US to consider that parechovirus may be the culprit when very young patients present with unexplained:

• fever
• sepsis-like syndrome
• seizures
• or meningitis (common symptoms include: high fever, irritability, loss of appetite, and sleepiness)

The federal health agency is urging doctors to test for PeV in infants who may have such signs and symptoms "without another known cause."

US surveillance for parechovirus is spotty: the CDC typically logs fewer than 50 parechovirus cases across the country every year.

In toddlers under 5, common symptoms can include an upper respiratory tract infection, fever, and rash. Most "children are infected by the time they start kindergarten," the CDC says.

Illnesses in toddlers and older kids are typically mild, but there are at least a few reports of children as old as 8 weathering severe infections of parechovirus, with fevers, rash, blurred vision, trouble walking, headaches, and confusion/altered mental status.

Parechovirus are generally most dangerous for babies younger than 3 months old, especially newborns who are younger than one month old, like Ronan was. Spinal fluid which is taken from infants who have a parechovirus often has few to no infection-fighting white blood cells in it.

"It's important in the first months of life to keep your baby away from anyone who is sick," Dr. Thomas Murray from Yale-New Haven Children's Hospital told WNTH.

Correction: An earlier version of this story misstated when Ronan was admitted to the hospital. He was 14 days old.