After receiving a COVID-19 vaccine, what is it safe for you to do?

About a year after the onset of the global pandemic, as the global death toll exceeds a staggering 2.3 million – nearly half a million in the United States alone – hope has arrived under the form multiple vaccines created in record time that have shown impressive success in preventing COVID -19.

“All vaccines have been very protective against serious illness, hospitalization, and death,” says William Moss, executive director of the International Vaccine Access Center at the Johns Hopkins Bloomberg School of Public Health. This, he says, is the most important achievement of COVID-19 vaccines and will help bring this brutal pandemic under control.

As the number of people vaccinated increases every day, many are asking: What previously risky activities, like hanging out indoors with friends or shopping without a mask, are now safer with a vaccine? This is what experts say on how to calculate the risks of certain common activities after being vaccinated.

The two mRNA vaccines currently approved for use in the United States, Moderna and Pfizer-BioNTech, involve two doses spaced three or four weeks apart. It takes one to two weeks after the second stroke to reach the maximum level of protection against COVID-19. In clinical trials, these vaccines are each about 95% effective in preventing cases of COVID-19.

At this point, it is not known how long the immunity will last after a person is fully vaccinated, and only time will reveal the answer. The COVID-19 vaccine could become an annual vaccine, similar to the flu vaccine; its benefits could last longer or shorter.

This question is critical, but has not yet been thoroughly investigated. The data available to date indicate that vaccination significantly curbs infection in people without symptoms. In Moderna’s Phase 3 clinical trial, a diagnostic test before the second dose of the vaccine showed that 89.6% of asymptomatic and symptomatic cases were prevented by the first dose.

Preliminary results from Phase 3 trials of the Oxford-AstraZeneca vaccine showed a 67% reduction in positive swab tests after vaccination.

This result is “really encouraging,” says John Swartzberg, clinical professor emeritus at the School of Public Health at the University of California, Berkeley. “It’s going to make me, as a responsible person, feel that I can be safer around other people.”

The decision of vaccinated people to come together involves a mental “math,” Swartzberg says, which should take into account the likelihood that someone will be exposed to the SARS-CoV-2 virus, vaccinated or not, as there is still a small luck, even one the vaccinated person could be infected.

Over time, as more people are vaccinated and the number of infected people continues to decline, Moss says a gathering among those vaccinated “will be safe” and continue to be safer.

“To be on the safe side,” says Cynthia Leifer, associate professor of immunology at Cornell University, “we should always practice distancing measures as much as possible in the short term until we achieve a wider distribution of the drug. vaccine.” She recommends that people continue to follow guidelines of avoiding large groups, wearing masks, and staying at least six feet apart.

There are also unknowns regarding the effectiveness of vaccines against new variants that have not been discovered.

“The more COVID is circulating right now, the more potential there is for variants to appear,” Leifer says. “We can’t predict when a new variant might emerge that may not be covered by the vaccine.”

The Novavax vaccine, which is not approved for use, has shown a significant drop in effectiveness – from 89.3 percent to 49.4 percent – against a variant that originated in South Africa, but which has since spread internationally. Pfizer and Moderna are still testing the effectiveness of their vaccines against a more contagious variant first discovered in the UK

Experts agree that everyone should wear masks, at least for now. Along with not knowing who is vaccinated and who is not, which could potentially lead to delicate and confusing situations, each person can have a different immune response to a vaccine.

“So you immunize 100 people, they’re all going to have varying levels of response to this vaccine; some may not be good enough to protect them, ”Leifer says. There’s really no way to know what kind of response your own body has had to the vaccine, so wearing a mask adds an extra layer of protection. The question remains open as to how many people who have received the vaccine will be able to transmit the virus.

“I think of the vaccine as a big patch, but there are other patches that we can have to protect ourselves,” says Swartzberg. “The vaccine is probably the most important.” Another such patch is a mask, and he doesn’t think anyone should stop using one.

For many, it’s been months or years since they’ve been able to meet family and friends face to face, but getting the vaccine doesn’t automatically mean it’s completely safe to travel the world.

“I think it depends on what people feel comfortable with, but they need to be aware that we cannot at this time predict when new variants will appear, where they will appear and whether you will be protected,” says Leifer. . “It’s not like when you get the vaccine, all of a sudden you have a Captain America shield around you.”

Swartzberg says he might soon feel safe socializing in small groups with other vaccinated people, air travel is a different story: “I’m not going to know who’s at the airport, who’s in the plane … so it’s going to be a lot longer before I’m convinced there won’t be many unvaccinated people on that plane or in that airport.

The laid-back world of 2019 may now be a distant memory, but with the vaccine rollout underway, a cautious sense of normalcy – dining out, going to school, karaoke night with friends – seems within reach. .

To date, more than 107 million people have been vaccinated worldwide. In the United States, about 3 percent of the population has been fully immunized. Estimates suggest that 70 percent of the US population will be at least partially vaccinated by mid-September at the current rate; researchers say between 75 and 80 percent of the population will need to get vaccinated before the country achieves herd immunity.

On the road to collective immunity, there will be signs that normalcy may return. Swartzberg says he will feel better as the number of new cases decreases, which will decrease the chances of being exposed to the virus.

“The way I see it unfolding is that it’s going to be kind of a phase transition into pre-pandemic times,” Moss says. The first step is to reduce cases, hospitalizations and deaths through vaccination so that thorough contact tracing can be implemented effectively. “Even though we talked about tracing, what happened was that the number of cases was so high in the United States that it just overwhelmed that system,” he says.

Leifer hopes the vaccine rollout can accelerate through creative distribution and manufacturing plans. “My vision would be that we get there by the end of the summer, so the students can go back to school,” she said.

A vaccine isn’t a golden ticket, but it does offer a way for people to reduce their risk and get back to their loved ones sooner.

“I haven’t kissed my grandchildren and kids, it’s been 10 months now,” says Swartzberger, “At some point I really need to.”