Doctors have developed a test that can determine how strong a baby’s immune system is at birth and how susceptible they are to colds in the first year after birth.

Researchers from Washington University School of Medicine have developed a method that identifies newborns with diminished immune response from a sample of umbilical cord blood.

“Viral respiratory infections are common during childhood,” lead researcher Dr. Kaharu Sumino said in a statement. “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.”

“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,” he added.

Investigators measured umbilical cord blood samples from 82 babies for a specific immune system response to viral infections known as interferon-gamma (IFN-gamma) protein by using isolated white blood cells from the samples and infected these cells with a common respiratory virus.

Researchers then compared the amount of IFN-gamma protein the cells produced in response to help fight the virus, and found that babies with immune systems that produced higher levels of IFN-gamma reported they had fewer colds over the year.

In contrast, babies who produced lower levels of the protein suffered more frequent colds, and were also more likely to experience ear and sinus infections, pneumonia and hospitalizations because of respiratory illness, according to the latest findings published in the May issue of the Journal of Allergy and Clinical Immunology.

The latest findings are similar to results from previous research in mice and human cells, and support the theory that boosting the body's innate immunity via the IFN-gamma signaling system could help babies to fight a wide range of viruses.

"Ideally, if these results are confirmed, we would like to be able to intervene based on knowledge of the innate IFN-gamma response," Sumino said.

"We're not there yet — measuring IFN-gamma levels is complex. But 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," he concluded.