HOUSTON, Texas (KTRK) -- Respiratory syncytial virus, or RSV, is the leading cause of hospitalizations for infants. It's a major risk for older children, too, and can be dangerous, even life-threatening, for those who are most vulnerable. On top of that, the younger the child, the higher the risk is.

Dr. Jaunita Mora with the American Lung Association joined Eyewitness News on Friday to discuss the organization's new campaign encouraging vaccinations for pregnant people, infants, and high-risk toddlers. She said nearly 100% of children will get RSV by age two, and that's why it's important to know how to protect them.

RSV symptoms are not usually severe at first. However, if coughing develops into wheezing or difficulty breathing, she said it's time to visit the doctor. SEE ALSO: Flu deaths in children hit new record as vaccination rates decrease: CDC To prevent serious illness, pregnant people, babies, and toddlers who are immunocompromised can get a vaccine.

"As a doctor, I'm happy to report the data looks phenomenal," Dr. Mora said. "It shows efficacy in decreasing the risk for severe RSV symptoms.

" The RSV vaccine is also recommended for older adults between age 60 and 74 who are at an increased risk of a severe infection. It's recommended for everyone 70 and older. For updates on this story, follow Briana Conner on Facebook , X and Instagram .

SEE ALSO: Vaccination numbers trending downward with fewer kindergarteners vaccinated, health expert says.