This is incorrect.
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The vaccines can’t give you COVID-19. Vaccines do not contain SARS-CoV-2, the virus that causes COVID-19. And the spike protein itself can’t shed.
“Spike protein is primarily made locally in muscle where the vaccine is administered and may possibly be seen in low levels in the blood," says Dr. Lawler. "But it should not be shed in significant quantity in respiratory or other secretions.”
If someone has tested positive for COVID-19, though, they are shedding virus, including the spike protein, and contagious. “We know that people with COVID-19 shed large amounts of virus from respiratory secretions,” says Dr. Lawler.