As the Delta variant spreads, there are fears of a 'pandemic of the unvaccinated.'

Doctors say the best way to stop the spread is through herd immunity. The White House says it will likely fall short of the president's goal of partially vaccinating 70% of American adults by Independence Day.

Dr. Valerie Brutus, of Hartford Healthcare St. Vincent's Medical Center in Connecticut, says the vaccine works and the side effects are minimal. Brutus says she really encourages people to get vaccinated.

Brutus says the Delta variant is more dangerous and can lead to more serious complications. She says the most vaccine hesitancy is among those 18 to 25.

The Delta variant, which began in India, now accounts for 20% of all new cases in the U.S. It's highly contagious especially with more people commuting on mass transit and taking vacations.

Dr. Brutus says people are afraid of side effects when it comes to the vaccine. She says if people learn more and know the side effects are minimal then maybe more people would get vaccinated.

Some people are against vaccines, something that Brutus says she has heard from patients. She hopes the seriousness of the new variant might sway people to change their minds.

There are also parents who are worried about getting their kids vaccinated because of myocarditis. Brutus says parents should look out for chest pain or palpitations, but says the cases are rare.