This is the worst season for RSV they have ever seen, physicians at OU Children’s Hospital said.

The hospital is seeing 50 to 100 more kids in its ER per day compared to the rest of the year.

Officials said monitoring the child's breathing might be the easiest way to identify the virus.

“They’re breathing really fast. They are sucking in on their ribs. If you look down the sides of the their chest where their ribs meet their belly, you can clearly see their ribs,” said Dr. Katherine Grant.

Meanwhile, Dr. Robert Welliver, who specializes in pediatric infectious disease, is helping in the development of the RSV vaccine.

The OU physician performed clinical trials for Novavax in the development of a shot that would be given to pregnant mothers in their third trimester.

“They can develop reasonably high antibody levels they can pass to the infant,” Welliver said.

He said the shot provides about 40% protection against hospitalization for RSV in babies.

The RSV “mom shot” is ready to go but has not been brought to market, Welliver said.

Welliver thinks it is because an RSV vaccine given to babies is currently in phase three of clinical trials.

He said the RSV vaccine is at least a year away, but that’s close enough for companies like Novavax to not immediately come to market with an RSV medicine for mothers.

“They say ‘wow’ this could supplant us in the market if we go forward,’” Welliver said.