This month, researchers from the La Jolla Institute for Immunology in California found that the immune systems of 50 percent of subjects appeared to remember past exposure to other coronaviruses, which helped them fight off the new virus.
The team says its findings could lead to developing a vaccine using immune system T-cells, which fight off foreign invaders, rather than using antibodies.
Now, the nation’s top infectious disease expert says the results could also explain why some people who get the virus have mild cases and others end up on ventilators.
Dr Anthony Fauci said a new study, which found the immune systems of some people sickened with different coronaviruses recognized the new virus and fought it off, could be a key to explaining why some people get mild infections and others die of COVID-19. Pictured: Fauci, August 10
Fauci says it’s feasible someone who fought off a cousin of the new virus no more than five years ago has immune system cells that recognize SARS-CoV-2. Pictured: Members of the medical staff treat a patient who is wearing helmet-based ventilator in the COVID-19 ICU at the United Memorial Medical Center in Houston, Texas, July 28
‘One of the things that I don’t think has been emphasized very much at all during the attempt to address, scientifically, the COVID-19 outbreak, and vaccine development and testing, is that we’ve been focusing very exclusively on the antibody test,’ Fauci told McClatchy.
‘There’s another equally important component of the immune system.’
The new study was funded by the National Institute of Allergy and Infectious Diseases, which Fauci is the leader of.
It was also one of the first to see T cell ‘cross reactivity’ in people who have been exposed to other coronaviruses such as Severe Acute Respiratory Syndrome (SARS) or Middle East Respiratory Syndrome (MERS).
Cross reactivity occurs when proteins or antigens from one virus (in this case, SARS-Cov-2) are similar to those found from another virus.
Fauci says this is important for understanding how the body fights off the new coronavirus when it infects our cells.
‘If you look at it metaphorically, as an army with different levels of defense, the antibodies prevent the virus from getting in,’ he told McClatchy.
‘So that’s kind of like the first line of defense. For those viruses that do escape and infect some cells, the T cells come in and kill the cells that are infected or block them.’
He added that T cells – in someone who was exposed to a coronavirus strain decades ago – may not recognize the new virus.
However, it is possible for these white blood cells to recognize in the virus in someone who has had a more recent infection.
‘It’s conceivable that the T cells that you’ve made in response a couple of years ago…when you were exposed to a relatively benign coronavirus that causes the common cold, could actually hang around, and when you’re exposed to the SARS-Coronavirus-2, could have some degree of protection,’ he said.
It comes as Fauci called for every American to be wearing a face covering after photos went viral of a crowded school hallway in Georgia.
Nine people, including six students and three faculty members, have since tested positive for the coronavirus at North Paulding High School.
‘When I see sights like that, it is disturbing to me…There should be universal wearing of masks,’ he told ABC’s World News Tonight on Monday.
‘There should be [to] the extent possible social distancing, avoiding crowds. Outdoors [is] always better than indoors and [you should] be in a situation where you continually have the capability of washing your hands and cleaning up with sanitizers.’