PROVIDENCE – With the Delta variant now widespread, the World Health Organization recently repeated longstanding guidance that all people -- vaccinated or not – should wear masks. Some places in the U.S., including sprawling Los Angeles County, have advised mask-wearing for all indoors.  

But the CDC differs. 

Pandemic expert Dr. Ashish Jha on Thursday cut through the confusion, offering advice keyed to one’s vaccine status and where one lives. 

“I largely agree with the CDC,” Jha said during taping of the “COVID: What Comes Next” podcast. “What they’re really trying to do is say these decisions should be made locally and that's my view as well.” 

He gave the examples of Rhode Island and Massachusetts, which each have high vaccination rates and low numbers of new infections. Fully vaccinated people in the two states, he said, do not need to wear masks at indoor events with others who are fully vaccinated. 

“If you're hanging around vaccinated people in a low-infection community, you're fine,” said Jha. But it’s a different story in some other parts of the U.S., he said. 

“Let's say you're in southwest Missouri right now. What you're seeing is a horrible outbreak and vaccination rates are low. Even if you're vaccinated, I'd wear a mask.” 

Jha, dean of Brown University’s School of Public Health, addressed the latest study, published in nature, that suggests immunity acquired through the Moderna and Pfizer vaccines may last years.   

“It is more evidence, but not definitive evidence, that these vaccines are going to last a while,” Jha said. “We're going to have reasonably long-term immunity.” Further study will provide more definitive answers over time, he said. 

The scientist also discussed the emergence of yet another COVID-19 variant -- a new version of the troublesome Delta variant that has been dubbed “Delta Plus.”  

 “I just had a long conversation about this with people in India, where it was first identified and is really spreading,” Jha said. “I'm not super worried about it. I don't think it'll become a major problem. Delta is a major problem. I don't think [Delta Plus] will be a problem even bigger than Delta. but we don't know for sure.” Like others, he awaits more data. 

During recording of this 33rd episode of the podcast, Jha answered four audience questions. 

◘ A mother of three young boys living near Dusseldorf, Germany, asked Jha’s opinion on her government’s reluctance to recommend vaccinations for children aged 12 to 18. That group is eligible in the U.S. 

“I think people should be getting vaccinated,” Jha said. “I think kids should be getting vaccinated.” 

◘ A psychotherapist living in Wisconsin had several questions regarding Long COVID. Jha spent two minutes answering. 

◘ A Boston resident asked about home tests. Jha endorsed them, but said he hopes the price will come down. 

◘ A Rhode Island woman asked about the need for a booster shot for people who have received the Johnson & Johnson one-shot vaccine. Jha devoted two minutes to this topic, too. 

Available exclusively from The Providence Journal and the USA TODAY NETWORK, this podcast is hosted by G. Wayne Miller, health reporter for The Providence Journal.