Fauci: Herd Immunity 'Unlikely' If Enough Refuse Vaccine

"That's one of the reasons why we have to make sure we engage the community as we're doing now, to get community people to help us, for people to understand that we are doing everything we can to show that it's safe and that it's effective and that it's for the good of them as individuals and in society to take the vaccine", Fauci, the director of the National Institute of Allergy and Infectious Diseases, said.

Fauci explained that no vaccine in human history has ever had 100% effectivity rate, which means it prevents everyone who receives the vaccine from catching the disease it's created to protect against. Fauci said Sunday that if those figures hold true and a potential COVID-19 vaccine is only 75% effective, the USA population would not reach the herd immunity threshold that would kill the virus.

One-third of the respondents to a CNN poll last month said they would not try to get a COVID-19 vaccine, even if it's widely available and low cost. Even though 25% to 30% of people who got the vaccine would still be able to be infected by COVID-19, a 70% to 75% effectivity rate would be enough to produce herd immunity in most locales. Asked how the USA is performing on contact tracing, Fauci said: "I don't think we're doing very well".

"There is a general anti-science, anti-authority, anti-vaccine feeling among some people in this country, an alarmingly large percentage of people relatively speaking", he said.

"Some states are going to be A+".

He singled NY out for doing "really well", but declined to name the "C" states.

"There are some states in which the leadership and the decision [to open up] was a little too precipitous", he said. He warned those people that they're "not in a vacuum". The annual flu vaccine, on the other hand, only protects between 40% to 60% of the people who get it. "All of the people who have a grave danger of a poor outcome".

The first COVID-19 vaccines could be ready for emergency use later this year, once they clear Phase 3 of clinical trials successfully.

"If you go into the community and call up and say, 'how's the contact tracing going?' the dots are not connected because a lot of it is done by phone". The director of the National Institute of Allergy and Infectious Diseases also noted that U.S. officials have issues conducting contact tracing by phone, as people aren't willing to talk to authorities. He explained again that contact tracing is also hindered by asymptomatic people. He warned community spread is more hard to contain than spread in single location like a prison or nursing home.

"When you have community spread, it's insidious because there are so many people in the community who are infected by asymptomatic", he explained.

Contact tracing - the act of monitoring people who have come into contact with someone infected with the coronavirus - is seen as one of the most effective measures until a vaccine is developed.