THURSDAY, May 24 (HealthDay News) -- The immune response babies are born with affects their risk for colds in the first year of life, a new study finds.

"Viral respiratory infections are common during childhood," first author Dr. Kaharu Sumino, an assistant professor of medicine at Washington University School of Medicine in St. Louis, said in a university news release.

"Usually they are mild, but there's a wide range of responses -- from regular cold symptoms to severe lung infections and even, in rare instances, death," she said. "We wanted to look at whether the innate immune response -- the response to viruses that you're born with -- has any effect on the risk of getting respiratory infections during the baby's first year."

Sumino and colleagues analyzed umbilical cord blood samples taken in the delivery room from 82 babies and then tracked the babies for one year. All of the babies lived in a high-poverty area, the study authors noted. Eighty-eight percent of the babies had at least one cold during their first year, and the average number of colds per baby was four.

However, there was a wide range. Some babies had no colds and a few had as many as nine or 10, the investigators found.

The researchers noted that babies who had a weaker immune response to viruses at birth had more respiratory infections than those with a stronger immune response.

The study is published in the May issue of the Journal of Allergy and Clinical Immunology.

In the future, "if we can develop a relatively easy way to find out if someone has a deficiency in this system, we would like to be able to give a drug that can boost the innate immune response," Sumino said in the news release.

More information

The Nemours Foundation has more about children and the common cold.