The Centers for Disease Control and Prevention (CDC) estimates upwards of 140 million Americans have been infected since February 2020. That's about 43 percent of the population.
The estimate is based on testing and random screening.
“There's a random sampling of blood that's submitted for other reasons. And that's sent off and antibodies for COVID-19 are assessed," said Dr. Kevin Dieckhaus, Chief of Infectious Diseases at UConn Health.
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That means if you've had blood drawn for any reason, it may have been anonymously tested for the antibodies that indicate a past COVID infection.
The American Red Cross is also screening all blood donations for COVID antibodies.
Dieckhaus says that information helps health authorities get a more accurate picture of how the virus is spreading.
“Not every recognized case of COVID is reported to the authorities. We certainly have a number of these at home testing that's happening all the time. And those don't get reported. These [seroprevalence] surveys allow us to look at the population as a whole. And it allows for the error for the lack of reporting of those sorts of testing,” he said.
It also helps with tracking COVID variants. Some, like omicron and BA 2, are much more contagious.
“At the beginning of the pandemic, the question was, who's going to get it? And now the question is, why hasn't everybody gotten it?" Dieckhaus said.
Although we have seen breakthrough infections in people who are fully vaccinated, Dr. Dieckhaus said vaccines have done their part in keeping many people from getting sick.
The behavioral changes we made during the pandemic also play a role.
"So the social distancing, the wearing of masks, the behavioral changes related to if you're ill, you don't go to work, those are all going to limit transmission,” he said.
And some of it comes down to our individual immune systems.
“There's the possibility of exposure to other organisms that are similar to COVID. So for example, twenty percent of just the normal cold, are coronaviruses. And it's possible that prior exposure to colds in an earlier phase of life may have some lasting, minimal, but lasting, immunity that may have some impact on COVID,” he said.
Dr. Dieckhaus said there have also been a high number of asymptomatic infections. So many people who think they have never gotten COVID were actually infected at some point without even realizing it.
As to whether getting COVID is inevitable, Dr. Dieckhaus said it's hard to predict.
“Certainly this is something that we're going to be living with for the foreseeable future. I don't think that it's something where everybody is going to have this. It's likely that some people will have it multiple times, but hopefully the disease manifestation, the severity of illness, would be akin to influenza where it's a relatively minor illness.”
He does expect the COVID vaccine to eventually become an annual seasonal vaccine, much like the flu shot.
But he cautions just because you haven't gotten COVID up until this point, doesn't mean you are in the clear. Just look at Governor Lamont and Lt. Governor Bysiewicz.
“Not having been infected before certainly doesn't absolutely predict safety here," he said. "Don't let your guard down."
He recommends a booster shot to those who have not yet gotten it. Although about 65 percent of Connecticut residents received the first round of vaccines, only 40 percent followed up with a booster.