As more vaccines against COVID-19 show signs of being able to protect people from getting really sick, they are fueling hopes that some sense of normalcy is within reach. Two vaccines have been licensed for emergency use in the United States and are slowly entering weapons nationwide. And two other vaccine manufacturers have just reported pretty positive results – a crucial step on the road to adding tools to quell the pandemic.
As a result, people are looking forward to finally being able to hug their loved ones, travel, and go to work, school, or the store without fear of getting sick. But the rocky implementation of vaccines across the country, in addition to ensuring vaccination of enough people to achieve herd immunity and curb the spread of the virus, means it is likely to take some time for that hope to come true (SN: 19/10/20). Exactly how long it is not clear, although public health experts have said it can take until late summer or fall.
Still, each shot means you are less likely than the person who received it to get sick. And all vaccinated people, along with ongoing public health measures like wearing masks, bring us one step closer to the end of the pandemic and a breath of fresh air.
Between the whirlwind of information about the danger and the promise of COVID-19 vaccines, here are answers to some of the most common questions about shots.
How many vaccines are there in the United States?
Two mRNA vaccines, developed by Pfizer / BioNTech and Moderna, are becoming weapons across the United States. And the shots could soon be joined by at least one or two more.
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Novavax announced on 28 January that its vaccine is 89.3 per cent effective against COVID-19, according to a Phase III clinical trial in the UK. However, this vaccine is less effective against a variant of coronavirus that has emerged in South Africa (SN: 28/01/21).
And Johnson & Johnson announced on Jan. 29 that its vaccine had a 72 percent effectiveness against moderate to severe COVID-19 in the United States. This vaccine is also less effective in preventing this level of disease in people exposed to the South African variant, although it has prevented deaths (SN: 29/1/21).
Johnson & Johnson plans to submit emergency use authorization applications to the U.S. Food and Drug Administration in early February. It is unclear whether Novavax will do the same, as the company’s clinical trial in the United States is ongoing.
The FDA said mRNA vaccines were safe when it accepted their use. Is it still true?
Yes. Health experts have closely monitored newly vaccinated people and so far the vaccine has proven to be safe.
“We really have to weigh (vaccine risks) against a very imminent risk (of) getting infected and getting sick with this virus circulating everywhere,” says Natalie Dean, a biostatistician at the University of Florida at Gainesville. And so far, both Moderna and Pfizer vaccines have low risks compared to COVID-19 vaccines.
The FDA required vaccine developers to have two months of clinical trial safety data before applying for emergency use authorization. Vaccines have some side effects, such as fever, arm pain, redness at the injection site, headache, and feeling sick. These symptoms are not unexpected, as they are a sign that the immune system is up and running and are common side effects for vaccinations in general.
Some people have had severe allergic reactions to the Pfizer and Moderna vaccines. But all were quickly treated and none died.
Two studies led by the U.S. Centers for Disease Control and Prevention found that both vaccines have higher rates of allergic reactions: 11.1 cases per million vaccine doses for Pfizer and 2.5 cases per 1 million vaccines for Modern, that allergic reactions to the flu vaccine. which is 1.3 cases per million doses. Still, such reactions are "extremely rare," Nancy Messonnier, director of the CDC's National Center for Immunization and Respiratory Diseases, said in a Jan. 6 news release (SN: 1/6/21).
Why is it so difficult to get a vaccine?
Vaccine distribution in the United States has been affected by problems. Not only are there limited doses available for people in the groups who are currently eligible, but everyone who receives the Moderna or Pfizer vaccines needs two vaccines for complete protection (SN: 03/12/20).
Logistical problems also come in part because each state, sometimes down to the county or city level, is handling the situation in its own way, Barry Bloom, an immunologist at Harvard T.H. Chan School of Public Health, said Jan. 28 in a call with reporters. Who is eligible for the shots varies from place to place, causing confusion and frustration. This local response “is very difficult to coordinate, which I think is a real tragedy and an obstacle to knowing exactly where vaccines are needed, exactly how many doses should go, for which vaccines have facilities,” Bloom said.
The situation may change when the Biden administration begins implementing plans to help states accelerate the launch of the vaccine, including the administration of at least 100 million doses before April 30 (SN: 20/01/21).
There are also strong disparities between vaccinated regions of the world. The vast majority of vaccine doses – more than 39 million – went to the 49 richest countries in the world. Thus, while it is difficult to get vaccines in places like the United States, it is even more difficult in lower-income countries.
After receiving a shot, do we need to continue wearing masks and social distance?
Yes, wearing a mask and keeping your distance are still essential, even for people who have already received a shot.
Vaccines are very effective in preventing people from developing symptoms of COVID-19, but it is unknown whether vaccinated people can still become infected without symptoms and unknowingly spread the coronavirus to others (SN: 12/8/20). Not all vaccines stop disease and transmission. Influenza, pertussis, and polio vaccines, for example, can prevent people from getting seriously ill if they are infected, but those people can still be contagious.
Vaccinated people should follow public health guidelines to protect those who have not yet been shot, at least until scientists know more about vaccines and transmission. In addition, Pfizer and Moderna vaccines are not 100% effective, meaning that not everyone who gets vaccinated develops a robust immune response that protects against COVID-19. So with transmission rates still high in many parts of the world, including the United States, and with large amounts of population still unvaccinated, it’s best to be wrong as a precaution.
The Johnson & Johnson vaccine reported lower efficacy than Pfizer and Moderna. Should I get it?
Here are some reasons why it is worth taking the Johnson & Johnson vaccine if that is the one you have at your disposal.
It was effective at 85 percent to prevent people from dying from COVID-19. That is still a very high level of protection. In clinical trials, vaccine efficacy measures the fewer cases of disease occurring in vaccinated individuals compared to unvaccinated individuals.
“We would be holding a seasonal flu vaccine with 60 percent effectiveness,” Jay Butler, CDC deputy director for infectious diseases, said Jan. 29 during a press conference sponsored by the Infectious Diseases Society of America. (Influenza vaccines are usually 40 to 60 percent effective.) “While it’s disappointing compared to the 95 percent effectiveness of phase III clinical trials of vaccines (Pfizer and Modern) … it’s still not something that makes me want to not use or receive the vaccine myself, ”Butler said.
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It’s also a single shot, so people don’t need a second shot to get full protection. In addition to only having to be hit once, that also means fewer logistical issues to try to set up multiple appointments.
And if the FDA authorizes the Johnson & Johnson vaccine for emergency use, that would make millions of additional doses available in the United States and help alleviate the shortage of doses. This could speed up vaccinations and get back to normal faster.
I am vaccinated. Can I spend time with other people?
Yes, but still with the right precautions for now.
Having highly effective vaccines on hand certainly changes the ways risk is assessed, Dean says. But since it is still unknown what the vaccine may mean for transmission, vaccinated people should follow guidelines such as masking around people who have not yet received a shot and staying physically away. So, for example, a vaccinated employee should still hide at work if their colleagues and the people they can find are not yet vaccinated.
But if all members of a group have been completely vaccinated – and it’s been at least a week after the second dose to let the immune system protect optimally – there’s plenty of room to be more lenient.
“There are things I would be more willing to do once vaccinated,” Dean says. For her, that means spending time outside with a friend who has also been vaccinated. That equation may be different for others.
The state of vaccination is just one piece of the puzzle. It’s also important to consider how much transmission is happening in the community or how many people are in contact with other people, Dean says, as vaccines are not 100% effective.
And for now, it’s best to avoid travel, especially with emerging and more contagious variants, the CDC says. One that originated in the UK is on track to become a dominant strain in the United States in March (SN: 15/1/21). And the first two cases of a worrying strain in South Africa were detected in South Carolina on 28 January. No person had traveled or had connections to each other, suggesting that this variant is already circulating in communities.
When will researchers find out if COVID-19 vaccines can stop transmission?
It's hard to say.
Some preliminary data from Moderna’s clinical trials suggest that her vaccine can not only protect vaccinated people from developing symptoms, but also prevent infection in general (SN: 18/12/20). If people don’t get infected in the first place, then they won’t spread the virus to others. It’s still unclear if that’s the case and clinical trials are still underway that could help figure it out, Dean says.
One way researchers could find out if vaccinated people still get infected but show no symptoms is by monitoring their blood for immune responses against parts of the virus that are not in the vaccine. The main target of a vaccine-induced immune response is the coronavirus ear protein, which helps the virus break down in cells (SN: 28/04/20). But if people also have antibodies against other parts of the virus, it’s a sign that they were probably infected by the real thing.
Although vaccines do not prevent infection, they can reduce transmission. Vaccinated people who become infected with the coronavirus may have fewer symptoms or carry fewer viruses in the body, for example. Therefore, they may be less infectious and only be able to spread the virus for a shorter time. However, this would require specialized studies.
“It’s pretty easy to see if the vaccine is preventing an infection, so if a lot of work is being done against that, we have our answer,” Dean says. But if the protection of a vaccine falls into the middle (slowing down transmission but not infection), it will take longer to confirm it.
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What about these new coronavirus variants? Will vaccines protect people from them?
It seems that vaccines provide some protection. Recent studies have shown that antibodies circulating in the blood can still prevent some viral variants from entering laboratory-cultured cells (SN: 27/01/21).
In the laboratory, antibodies still recognize a coronavirus variant called B.1.1.7 that was first identified in the UK. Another variant that has emerged in South Africa, called 501Y.V2 or B.1.351, appears to pose a tougher challenge for current vaccines, avoiding some – but not all – antibodies.
Now researchers are getting clues as to how this might play out in the real world. While the Novavax vaccine had an efficacy of 85.6 per cent compared to B.1.1.7 in a clinical trial conducted in the UK, the efficacy fell to 60 per cent compared to B.1.351 in a South African clinical trial. The Johnson & Johnson vaccine was 57 percent effective in South Africa, but it prevented people there from becoming seriously ill.
The emergence of these variants makes reducing infection levels even more crucial, says Stuart Ray, a virologist and physician in infectious diseases at Johns Hopkins University. More infections mean more chances of the virus mutating even further and bypassing our defenses. Several vaccine manufacturers, including Novavax, Pfizer and Moderna, are designing new vaccines based on emerging versions of the coronavirus.
But for now, even with effective vaccines, public health measures such as wearing masks, socially distancing oneself, and avoiding crowds remain essential tools to help reduce infections and control the pandemic.
If we still have to wear masks and distance ourselves physically, what is the benefit of getting the shot?
On a personal level, getting vaccinated makes you less likely to get sick and need hospitalization.
Bigger picture, if there are fewer people who are seriously ill because they get vaccinated and because they continue to wear masks and physical distances, there are fewer people in suffocated health care systems who are already struggling to care for seriously ill COVID-19 patients.
And finally, once enough people are vaccinated, hugs, travel, and other rituals of normalcy will be less dangerous. When it is not clear, but each vaccination is a step closer.
Personal writer Jonathan Lambert contributed to this story.