LOS ANGELES - People everywhere are searching for answers to bring an end to the COVID-19 pandemic. One term that is being thrown around a lot is "herd immunity." So what exactly is it? Will it protect us from the deadly disease? Los Angeles Public Health Director Dr. Barbara Ferrer stopped by Good Day LA Friday to answer those questions.
"Herd immunity means that many people in the community have already seen the virus, and they’ve developed what we call antibodies to the virus, so they have some protection, should they see the virus again," Ferrer explained. "It’s not clear what protection you have from COVID-19 because you have antibodies, but as with most other viruses, we assume you have some protection."
In other words, the idea of herd immunity is once the majority of a population is protected from the virus, either because they were exposed to it or vaccinated, it will be much less likely that the infection can spread widely from one person to another — because most people will not be susceptible. Herd immunity can only be achieved if roughly 70% of the area's population has antibodies to the virus in their system.
"The other way we get immune if we don’t get sick, is we get vaccinated. And we obviously don’t yet have a vaccine, so the only way to develop antibodies right now is if you’ve been infected, and as I said, we’re not sure how much protection that affords you, but it does help us with this idea that there’d be some immunity,” said Ferrer.
A few weeks ago, LA County conducted a serology test on a random sample of residents in order to see whether they had developed antibodies to COVID-19.
Based on the results of the first round of testing, which was conducted on 863 adults, the researchers estimated that 4.1% of the county's adult population has an antibody to the virus, meaning they have SARS-CoV-2 antibodies in their bloodstream.
"That means 95% of us have not yet seen the virus, we don’t have any antibodies and it, in fact, would take us a while to develop that herd immunity," explained Ferrer. "Until you have that herd immunity, you have to really worry about how easily we’re able to transmit — to each other — this infection. Because most of us have no immunity at this point in time."
Ferrer said that as they look at the possibility of reopening the economy in the next few weeks, they will be doing so "sensibly, knowing that 95% of us still need a lot of protection, and the only protection we have right now is to keep our distance from each other."
She added that residents will all need to continue to play their part in terms of good public health hygiene, washing your hands often and if you’re sick, you need to get tested.
“If you are positive, then you have a lot of responsibility to stay away from people, that’s for at least 10 days now, and to identify your close contacts who need to also need to stay away from people for 14 days. That’s the way we prevent ourselves from transmitting the virus from one person to another when we don’t yet have a vaccine," said Ferrer.
According to the Mayo Clinic, a COVID-19 vaccine is likely at least a year away.
Watch Dr. Ferrer's full Good Day LA interview below.