January and February are expected to be the worst for flu, RSV and COVID-19. Infectious disease experts say now is the time to exercise vigilance.
Respiratory viruses can find you anywhere.
"I have no idea where I got it from. No idea. I didn't know anybody who was sick," said Arcelia Gallegos of Los Angeles.
Gallegos, a breast cancer survivor, says she's been careful to stay away from sick people but she still ended up with a fairly severe Respiratory Syncytial Virus infection.
"I thought I had a cold, but it was RSV l. I went to the doctor and yeah I was really sick. I thought it was COVID at first, but it wasn't, thank God," she said.
"It's not just COVID. It's not just influenza, it's not just RSV. We're seeing combinations of them, so you're seeing RSV plus COVID and influenza plus COVID," said infectious disease specialist Dr. Suman Radhakrishna with Dignity Health California Hospital Medical Center.
She said she is seeing many patients with double infections. They are mostly elderly and immunocompromised individuals, but she says everyone is at risk.
"Even if you were healthy, it brings your immune system down and now if you have influenza or COVID along with RSV, you feel miserable and terrible for a longer period of time," Radhakrishna said.
Her advice is get the flu shot. If you're over 60 or if you're pregnant, talk to your doctor about the RSV vaccine.
And if you haven't received the latest COVID shot yet, get it because it could jump start your protection within days.
"To boost that immune response, a week should be more than adequate," she said.
Due to the post-holiday surge, Los Angeles County has reinstated a mask wearing requirement for staff and visitors at all licensed healthcare facilities and on public transit, and in transportation hubs.
"It is generally recommended until the surge goes down that you mask," Radhakrishna said.
"I mean, the masks are good thing - especially for someone like me. Because with a compromised immune system, I can get it anywhere," said Gallegos.
Most COVID hospitalizations and deaths are among those 65 and older.
Health officials say if you haven't gotten it, now is the time to get the latest COVID shot. In L.A. County, only 10% of residents 6 months and older are up to date.