Just a few days after announcing he had tested positive for COVID-19, Maine Sen. Angus King is recovering well, according to his spokesman.

“He’s on the mend, feeling better, following his doctor’s guidance,” Matthew Felling, a spokesman for King, said Monday.

King, 77, is the oldest of Maine’s four-member congressional delegation. He announced last Friday that he had tested positive for COVID-19, as the delta variant of the virus has been surging across the country.

King was vaccinated against the virus, along with about 500 other federally elected officials in January. He has been an ardent supporter of vaccination and other precautions, including masking, meant to end a pandemic that has gripped the U.S. for more than 18 months.

In a statement announcing his positive test, King again advised those still unvaccinated against COVID-19 to get inoculated.

“Get vaccinated, if you haven’t been,” King said. Felling said Tuesday that King was not prepared to give interviews yet.

In Maine, 95 percent of the 125,000 people in King’s age group, those over 70, have been vaccinated against the virus, according to the latest data from the Maine Center for Disease Control and Prevention.

In a phone interview Tuesday, U.S. Sen. Susan Collins, R-Maine, said she had spoken with King on Monday.

“He told me he was feeling much better and felt he had turned the corner,” Collins said. She said King also remarked, as have other U.S. senators who have contracted COVID-19, that their doctors told them they “would have gotten the disease much more severely had they not been vaccinated and the fact that they were vaccinated kept them from hospitalization or even worse outcomes.”

Collins said she believed more and more people would be willing to be vaccinated now that the FDA has given its full approval to the Pfizer vaccine. Collins said based on briefings she’s attended as a member of the Senate’s committee on Health, Education, Labor and Pensions that the two-dose vaccine from Moderna would also soon receive full approval.

While vaccinated individuals can still contract COVID-19, they are far less likely to require hospitalization or die from the illness, as the vaccines help a person’s immune system more effectively recognize and fight off the virus. Vaccinated individuals also are far less likely to experience severe symptoms, but the delta variant, which is far more easily transmissible, is making the spread of the virus  more difficult to prevent.

The most recent data from the U.S. Centers for Disease Control and Prevention show that the majority of new COVID-19 infections are among those who have not been vaccinated, but breakthrough infections among vaccinated people are increasing as the pool of those who have been inoculated continues to grow.

King, an independent who caucuses with Democrats, was among three U.S. senators who announced they had tested positive for the virus last week, including Democrat John Hickenlooper of Colorado and Republican Roger Wicker of Mississippi. Both Hickenlooper and Wicker were also vaccinated and both men were also reporting that they were feeling better on Monday.

At least 10 other senators and about 60 members of the House of Representatives have reported positive tests since the first case of COVID-19 was detected in the United States in January of 2020.