March 6 (HealthDay News) -- Stress at home could boost kids' risk for fever when they come down with illness, a new study finds.

"These findings are somewhat surprising to me but also exciting, because they show us possible new avenues for improving children's health," principal investigator Dr. Mary Caserta, associate professor of pediatrics at the University of Rochester, N.Y., said in a prepared statement.

Her team published its findings March 5 in the journal Archives of Pediatric and Adolescent Medicine.

She noted that fever is often a sign of an infection. The findings of the study, one of the first to examine the effects of stress on children's immune systems, suggests an association between family stress and susceptibility to infectious diseases, Caserta said.

The three-year study, which followed 169 children ages 5 to 10, also found that children's natural killer cell function (part of the immune system) increases under stress. That was a surprise, since in adults stress decreases natural killer cell function.

"It may have something to do with the fact that children's immune systems are still developing. Or maybe they're compensating for a defect someplace else. More research is needed to figure out why," Caserta said.

She and her colleagues now want to look more closely at the types of parental and family stress that cause illness and fever in children.

"Once we understand these connections, we can design interventions that lower family stress, or help families to better manage stress in their interactions -- and lead to healthier kids," Caserta said.