“Most of us in infectious disease really attributed that to masks — not just masks, but the combination of masks, people working largely from home, social distancing, all of those measures that have been in place for the last year,” said Dr. Joshua Barocas, an infectious diseases physician at Boston Medical Center.
But as vaccination rates increase and such precautions are slowly scrapped, other viruses will start to resurge, starting with colds and other viruses later this summer, and the flu come fall and winter.
On Thursday, the Centers for Disease Control and Prevention issued a health advisory about increased cases of respiratory syncytial virus, or RSV, across parts of the southern United States — something they hadn’t seen since April 2020, when cases “decreased rapidly.” RSV is a cold-like respiratory illness that produces symptoms similar to COVID, and can cause severe illness in older adults and young children.
Since late March — about the time COVID vaccines began to be widely available — cases of RSV have been on the rise in the South. Though the trend hasn’t yet reached the North, where the public was slower to unmask en masse because of lingering restrictions, experts predict that it will.
“I imagine it’s going to start expanding to all of the other states as well, as the mask mandates are lifted and as people start socializing more and spending more time together,” said Dr. Helen Chu, an infectious disease specialist at the University of Washington.
Chu predicted that the return of viruses like RSV and influenza could be somewhat mitigated by the continuation of public health measures in schools this fall.
Masks are among the most effective of such measures, she said, because much of virus transmission is droplet based, expelled from one person’s mouth or nose and into another’s.
“Having that mask on prevents that type of droplet-based transmission pretty well,” Chu said.
For that reason, Barocas said he will likely continue to wear a face mask in situations that present an elevated risk of cold or flu transmission — like a large holiday gathering or night out at a crowded bar.
“I want to lower my risk of respiratory infection. I don’t really want to miss work,” Barocas said. “And to me, wearing a mask is such low-hanging fruit that I’ll probably do it in a lot of social situations.”
He also noted the protection face masks afford from pollutants in the air and common allergens like pollen.
Dr. Nahid Bhadelia, the founding director of the Boston University Center for Emerging Infectious Diseases Policy and Research, said she recommends her patients keep their masks on hand.
“I would advise my patients — particularly those with high-risk medical conditions, including immunocompromising conditions — to consider wearing a mask in crowded indoor places during flu seasons and during long travels in the future,” Bhadelia said. “I am likely to do the same.”
Chu agreed with that advice.
“I hope that we continue it, especially in high-risk places like hospitals and nursing homes,” she said. “I think in those places, we really do need to mask — and schools. Those are places where transmission is happening, and vulnerable people are congregating.”
Chu added that she and other infectious disease doctors are concerned about how children will handle the upcoming flu season.
“All of us in infectious diseases are just holding our breath right now to see what happens when the flu comes back, because it is heading into an environment where children have not seen it,” she said. “For many of them, this will be their first exposure, and I’m just worried about how sick they might get once they get it.”
Barocas anticipates sending his children to school with masks this fall, regardless of whether or not their schools require them.
“Quite honestly, it’s been really nice not having my kids have the colds and sore throats that keep them home from school, and it’s highly likely that my wife and I will encourage our kids to bring their masks to school and wear them for part of the day,” he said. “At the very least, it’s going to reduce their risk a little bit.”
Camille Caldera can be reached at camille.caldera@globe.com.