WORCESTER, Mass. - With many people headed back to work or school this week, doctors are warning of a possible increase in illnesses after the holiday season.

Saint Vincent Hospital's Chief of Medicine Dr. George Abraham said while it's not required, he recommends people mask up for at least the first five days after break to prevent the spread of the flu, COVID-19 and RSV.

Abraham said if you feel sick, stay home until symptoms are gone. He said right now, there's a high rate of flu cases and while they anticipated it, the flu season is just getting started and typically runs through March.

"What we are seeing now is nothing out of the ordinary, but expected,” Abraham said. “So does that mean the other infections, RSV and COVID don't matter? Absolutely not. We are seeing people with more than one infection together at the same time and RSV continues to be an issue.

“While it was primarily more relevant in children, we are seeing more adults, so parents and grandparents of children who got it infected who themselves come down with the same thing, and if they have a lung condition or other health conditions which make them more vulnerable to such infections, they end up in hospital with more severe illness."

The flu, COVID-19 and RSV are all airborne viruses. Abraham said it's not unusual to see more than one infection in someone, but when two or more occur together, the risk of complications increases significantly.