It is not necessary for children under 2 to wear face masks amid the ongoing coronavirus pandemic because they can even pose serious health hazards, according to a statement by the Japan Pediatric Association issued May 25.

The association is calling for parents to exercise caution with masks and small children, pointing out that while masks are safe for adults, they can be dangerous for infants and may cause them to have difficulty breathing.

According to a statement by the association, because infants’ respiratory systems have narrow air passageways, wearing face masks can make it difficult for them to breathe and can place a heavy burden on their hearts.

Masks increase the risk of suffocation for babies by the protective gear alone or they could choke on their vomit, the association warned.

“Infants often vomit, so they might suffocate or develop pneumonia because of the masks,” said Akira Kamikawa, chairman of the Japan Pediatric Association.

Masks also increase the risk of heatstroke because they keep babies’ faces warm.

“Heat does not escape from inside the masks, so there is a high risk of getting heatstroke,” he said.

It also takes longer to notice health problems because masks hide the color of their faces and lips, as well as their facial expressions.

The U.S. Centers for Disease Control and Prevention (CDC) issued a similar warning, indicating children younger than 2 should not wear masks due to the risks of suffocation.