Covid vaccine: cases in Congress show one dose may not fully protect against coronavirus

Can you still get Covid-19 after receiving a vaccine? And can you still spread the virus that causes it to other people? As more Americans begin the immunization process, the protection offered by each dose in the real world is put to the test.

At least three Democratic members of the House of Representatives recently found out the hard way. They took refuge for hours with fellow Republicans who refused to wear masks during the Capitol riots on January 6 and then tested positive for SARS-CoV-2, the virus responsible for Covid-19. Their experience suggests that one dose of vaccine and masks may not be enough to protect someone from hours of reckless behavior.

Representative Bonnie Watson Coleman (D-NJ) reported on January 11 that she tested positive for SARS-CoV-2 and started to experience symptoms, even though she had already received a dose of the Pfizer / BioNTech vaccine December 29. Watson Coleman, 75, a cancer survivor, said she may have been exposed on the U.S. Capitol during the riots as she took shelter with other officials who refused to wear face masks .

“[S]he is always hidden and that included the time she was locked out on Capitol Hill, ”a Watson Coleman spokesperson said in an email.

Another congresswoman who was in the same lockdown area on Wednesday with colleagues without a mask, Representative Pramila Jayapal (D-WA), announced on Monday evening that she had also tested positive. The Cut reports that she received the vaccine on January 4.

On Tuesday, a third Democratic lawmaker, Representative Brad Schneider of Illinois, who was also vaccinated on Jan.4, said he had tested positive for the virus but showed no symptoms.

“Today, I am now in strict isolation, worried about having risked my wife’s health and angry with the selfishness and arrogance of the anti-masks who convey their own contempt and contempt for decency before the health and safety of their colleagues and our staff, ”he added on Twitter.

The vaccines for Covid-19 that have been approved to date are very effective, but the new group in Congress reminds them that they are not perfect, especially not at a dose.

The Moderna vaccine and the Pfizer / BioNTech vaccine are both believed to be around 95% effective in preventing Covid-19 disease after two doses, but that means a tiny fraction of those vaccinated could still get sick.

And because the two doses of the two vaccines are supposed to be given 28 and 21 days apart, respectively, it is also possible that people could become infected between their injections. Although the first dose of the vaccine offers some protection, this protection takes days or weeks to build up, and it is not as complete as the shield provided by two doses.

Testing positive for the virus does not necessarily mean that an individual will suffer from the disease and show symptoms. But that could mean that they can still pass the virus on to others.

The possibility of becoming infected even after starting an inoculation regimen was evident during clinical trials of Covid-19 vaccines.

In Pfizer and BioNTech’s emergency use authorization request from the Food and Drug Administration, they reported 178 cases of Covid-19 among participants in their Phase 3 clinical trial, with nine cases in the group having received the vaccine. The majority of these nine cases were between the first and second dose.

FDA

Moderna’s Phase 3 trial showed a similar pattern, with 185 cases of Covid-19 in the placebo group and 11 cases in the vaccine group, most within two weeks of the first dose.

FDA

For both vaccines, it is also possible that some of the people who reported symptoms of Covid-19 were infected before receiving their first dose of the vaccine. In rare cases, people can get sick even after two doses, but the evidence points to a less severe course of the disease among those vaccinated.

It’s important to note (as there is a lot of misinformation circulating on social media) that vaccines themselves cannot cause infection. Moderna vaccine and Pfizer / BioNTech vaccine do not contain any part of SARS-CoV-2. Instead, they use a strand of genetic material called mRNA that tells the body to make a fragment of the virus.

There is even more to learn about the protection offered by Covid-19 vaccines

A lingering concern about Covid-19 vaccines is that protection might not last forever. Since Covid-19 is still a relatively new disease, and there are only a few months of data on who received the vaccine, scientists are still trying to figure out how quickly immunity might wane. Based on experiences with coronaviruses in the past, scientists expect protection to last for a few years, but this is something that can only be verified over time.

Another important question is whether someone can pass Covid-19 to others after being partially or fully vaccinated. Some early evidence from Moderna has shown that its Covid-19 vaccine blocks some transmission, but it may not be to the same extent that it prevents disease.

Determining this will take time, especially since many SARS-CoV-2 infections are asymptomatic and require testing to confirm. Researchers recently reported that up to half of infections are caused by people who are infected but do not show symptoms themselves, so it is important to determine to what extent asymptomatic transmission can still occur among those vaccinated.

If a vaccine blocks transmission well, it means it can provide a faster route to herd immunity. But since there are currently so many unknowns, people who have been vaccinated against Covid-19 should still follow all of the usual Covid-19 precautions, such as hand washing, wearing masks and social distancing, in particular. when community transmission is as high as it is now. Vaccines are essential, but they are only a line of defense against Covid-19, and as recent infections of members of Congress show, preventing transmission requires others to take precautions as well.