WEDNESDAY, Jan. 6, 2021 (HealthDay News) -- A return to normal life in America might happen sooner than many expect, one of the nation's leading vaccine experts told HD Live! this week.
As the new coronavirus rages across the country, President-elect Joe Biden has set a goal of one million doses of vaccine delivered every day once he takes office. If that ambitious target is realized, everyday conditions in the United States might return to normal as soon as the summer, said Dr. Paul Offit, director of the Vaccine Education Center at the Children's Hospital of Philadelphia.
"I think if we can do that, if we can get a million people vaccinated a day, I think then that by summer or late summer we should be able to have enough people vaccinated that we are able to have a normal life again," Offit said during an HD Live! interview.
So far, the rollouts of the Moderna and Pfizer vaccines have been rather rocky.
Only about 4.2 million people have had the first of two doses, according to a U.S. Centers for Disease Control and Prevention tracker -- far fewer than the 20 million doses that Trump administration officials promised to put in people's arms by the end of 2020.
But Americans are further ahead than many might think in one crucial aspect, Offit said -- a good chunk of the U.S. population has already contracted the coronavirus and are unlikely to get sick again.
About 20 million people in the United States have tested positive for COVID-19 infection, but that number doesn't include millions who only had mild or asymptomatic infections and were not tested at all, Offit said.
"If you look at antibody studies, which is a much better marker for how many people have really been infected with this virus, that 20 million figure is probably off by a factor of three," Offit said. "It's probably more like 60 million people in the United States who have been infected. That's about 20% of the U.S. population who, when they are exposed to this virus, are very unlikely to get sick, or not very sick."
That's not far off from the results of a new study published online in JAMA Network Open this week, which attempted to provide a more accurate estimate of COVID-19 infections by taking into account the underreporting of cases.
More than 14% of the U.S. population probably had been infected by mid-November 2020, the researchers estimated after applying region-specific multipliers from five different CDC antibody studies to confirmed case reports.
"When we talk about immunizing 70% or 80% or 90% of the U.S. population, there's 20% of the population that's already immune. We probably don't need to vaccinate the larger percentage we're thinking," Offit said. "I think if we get to 70% vaccination rates we can dramatically slow the spread of this virus. Hopefully, we can get there by late summer."
Progress will be marked in the number of infections, hospitalizations and deaths that occur every week, Offit said.
"You should see a gradual diminution in cases, hospitalizations and deaths. That's when you'll know the vaccine is working," Offit said.
It won't be known until time passes how long the vaccine's protection will last, but Offit suspects it will prove long-lasting.
"You don't know how long efficacy is going to last, but you know with 95% efficacy after two or three months you can feel pretty comfortable this is going to be highly effective for a while," Offit said.
That was recently confirmed by a study in the journal Science Immunology, which found people infected with COVID-19 carry immune memory to protect against reinfection for at least eight months.
Although antibodies rapidly dwindle in COVID-19 patients, these folks continued to carry stable levels of virus-specific memory B-cells for up to eight months following infection, Australian researchers reported.
By the late summer, COVID-19 will remain a threat but one against which people can reasonably weigh their personal risk, Offit said. To provide a comparison, he noted that the United States suffered 700,000 influenza hospitalizations and 60,000 flu deaths in the flu season prior to the pandemic.
"If we wore masks and social distanced every winter, we would dramatically reduce those [flu] numbers, but we don't," Offit said. "We live with that. I think it may come down to that with this -- when do we get to the point where we say, you know, we can live with this level of disease."
People should feel good about the safety of the two vaccines, said Offit, who serves on the U.S. Food and Drug Administration's advisory panel that reviewed them prior to approval.
Folks with chronic health conditions like diabetes, lung disease and heart disease were included in the trials to make sure the vaccine was safe and effective for them, and it was, Offit noted.
"The only people who really can't get this vaccine are those who have ever had a serious allergic reaction to any component of this kind of vaccine. That's it," Offit said. "Even people who have had severe allergic reactions otherwise, like to food items like peanuts, they can get this vaccine. They just have to wait for 30 minutes in the office where they're getting it to make sure they don't have a severe allergic reaction."
The U.S. Centers for Disease Control and Prevention has more about COVID-19 vaccination.
SOURCE: Paul Offit, MD, director, Vaccine Education Center, Children's Hospital of Philadelphia