Omicron caused spike in breathing condition in babies and toddlers, study finds

Enlarge / Parents look after their son, age 5, who is being treated for croup and asthma in an emergency room at a California hospital March 24, 2010. (credit: Getty | Mark Boster)

The omicron coronavirus variant caused a spike in cases of a potentially severe breathing condition in babies and toddlers, according to a hospital study recently published in the journal Pediatrics.

The study is small, focusing only on COVID-19-associated cases at one large children's hospital in Massachusetts during the pandemic. But, it provides some of the initial data on the subject and backs up anecdotes from health care providers that the latest pandemic variant causes more cases of laryngotracheobronchitis—aka croup—in younger children than earlier variants.

Generally, croup is a common upper-respiratory tract condition in which significant inflammation and swelling develop in the larynx and trachea, imperiling breathing. Some viral infection usually triggers swelling, but allergies and other irritants can also be culprits. Croup can occur at any age but mostly strikes the tiny upper airways of infants and young children, ages 3 months to 5 years.