'Very reasonable' for local officials to reimplement mask mandates amid delta surge: Dr. Vivek Murthy

Local officials have the right to reimplement mitigation strategies to stop the spread of COVID-19 amid a surge in cases fueled by the delta variant, U.S. Surgeon General Dr. Vivek Murthy said Sunday.

"Unfortunately we're seeing rises, particularly among the unvaccinated in many parts of the country now," Murthy told ABC "This Week" co-anchor Martha Raddatz.

Approximately 97% of COVID-19 hospitalizations in the U.S. are among the unvaccinated and at least 58% of current reported cases were directly linked to the delta variant. At the end of May, the variant was estimated to account for just over 3% of new cases.

The Centers of Disease Control and Prevention has for the last two months said that vaccinated individuals can enter public, indoor spaces without a mask. Amid a surge in cases, Los Angeles County reinstated its indoor mask mandate in all public places for all individuals, regardless of vaccination status and at least 10 additional counties in California, including the city of Berkeley, have highly recommended all residents wear masks indoors again.

"In areas where there are low numbers of vaccinated people, where cases are rising, it's very reasonable for counties to take more mitigation measures, like the mask rules coming out of LA," Murthy continued. "And I anticipate that will happen in other parts of the country -- and that's not contradictory to the guidance the CDC issued."

Los Angeles County Board of Supervisors Chair Hilda L. Solis told Raddatz in a separate interview on "This Week," that the new mask mandate was not punishment for the vaccinated, but prevention.

"We still have 4 million people out of 10 million that haven't been vaccinated -- and many of them are young people," Solis told Raddatz. "And we're seeing that this transmission is so highly contagious that it will cost more in the long run."

Murthy reinforced his support for LA County's decision as an acceptable mitigation approach based on data on the ground. The county reported over 1,000 new COVID-19 cases daily this past week.

"We saw this during the last year of the pandemic, that we have large numbers of people gathering in indoor spaces that is the right setup for COVID-19 to spread," Murthy said, adding that the Centers of Disease Control and Prevention will provide surge response teams to assist regions experiencing high coronavirus cases.

Raddatz asked Murthy about the World Health Organization's warning that the delta variant and three additional variants of concern could prolong the pandemic and possibly lead to the emergence of deadlier strains of COVID-19.

"If we don't get this under control now, what do you anticipate the fall looking like?" Raddatz asked.

"I am deeply concerned," Murthy responded. "We've made so much progress over this past year, but what I worry about are those that we still have -- millions of people in our country who are not vaccinated."

"We have to still protect our children under 12 who don't have a vaccine available to them." Murthy added. "Our kids depend on the people around them being protected, being vaccinated in order to shield them from the virus. And that's why, again, it's so important for us to get vaccinated."

Raddatz also asked Murthy about his recent warning about COVID-19 misinformation online and the president's suggestion that platforms like Facebook are "killing people."

"Facebook officials say stop pointing fingers. They've already tried to get about 18 million pieces of COVID misinformation down. What should they do?" Raddatz asked.

"I've been deeply concerned about the flow of misinformation across technology platforms and throughout society over the last many months," Murthy responded.

"I've called for greater transparency in terms of the data that they have to share with independent researchers so we can get a better sense of how much misinformation is flowing on these sites and what strategies are working to address them," he added.

"I also ask people across our country to stop and verify your sources, before you post stories online," Murthy concluded.