Across the Bay Area, hospitals are taking extra measures to help handle the surge.
UCSF Benioff Children's Hospital has even set up a tent.
Randi and Chase Thomas are heading home with their son after a quick visit to the doctor.
They went to the hospital for a different reason.
But they know very well about the surging number of RSV cases.
"Right now it's going around our younger sons' preschool classroom," said Randi Thomas.
"As parents, it's scary to know that if your kid is sick, you may not have somewhere to take them," said Chase Thomas.
Hospitals see RSV cases every fall. They usually start in Nov. and go thru April. This year, they started in Oct.
Right now, UCSF Benioff Children's Hospital in San Francisco is operating at capacity.
Beds are full. But they're still accepting patients.
They just set up this tent with room for seven beds. They call it a flex space.
"In that tent, is a space for patients with lower acuity conditions, sprain or ankle sprain or simple earache," said Dr. Joan Zoltansky, CMO of UCSF Benioff Children's Hospital.
UCSF Benioff Children's Hospital in Oakland is also making room for more young patients.
"We have space in Oakland. It's equivalent to a tent, it doesn't happen to be a tent. It's what we call an annex space in Oakland where we often take care of patients when our emergency rooms are full of patients," said Dr. Zoltansky.
Stanford's Lucile Packard Children's Hospital has also taken steps to help keep hospital beds open.
According to a written statement, "Stanford Children's is deferring and rescheduling some elective clinical surgeries amid the respiratory illness surge in order to ensure that we have the capacity to care for our most at-risk young patients."
Kaiser Permanente says it is increasing staffing and expanding alternate space when needed. They too, are seeing more cases of pediatric respiratory illnesses this time of year from RSV and the flu.
Parents say any extra steps hospitals take offer a peace of mind.
"I think they're planning ahead for a surge. That's what we want, right? I really appreciate all the extra precautions they're taking to make that available," said Randi Thomas.
If you're on the ABC7 News app, click here to watch live