But as the vaccine has rolled out, so have the questions: Who should get it? What’s safe to do once you’re vaccinated? What about breakthrough cases?
Here are the answers to your most frequently asked questions about the vaccine, including its effectiveness, its risks, and what to expect when it comes to side effects.
How can I get the COVID vaccine?
Vaccine distribution got off to a patchy and confusing start, with some states rolling out faster than others to different priority groups, but vaccines are now widely available across the U.S. and eligibility has expanded to include everyone age 12 and up. The pace of vaccinations reached a peak of over 3 million shots per day in April before starting to decline.
More than 62% of eligible people in the U.S. (ages 12 and up) were fully vaccinated as of early September, the CDC reports, and over 73% have gotten at least one dose.
Doses are available — at no cost — at thousands of vaccination sites and pharmacies across the country.
To find a location near you, visit the website vaccines.gov, text your ZIP code to 438829, or call1-800-232-0233 (the CDC says the call center operates in 150+ languages).
When can children get the vaccine?
The Pfizer vaccine received authorization in May for adolescents age 12 to 15 after clinical trial results showed it is safe and effective in that age group. That has allowed many students to get vaccinated against COVID-19 before the start of the school year.
What are the differences between the COVID vaccines?
In December 2020, the FDA authorized emergency use of the first two coronavirus vaccines in the U.S., one made by Pfizer and BioNTech, and the other by Moderna. Both require two doses. A third vaccine, from Johnson & Johnson‘s Janssen Biotech division, got FDA authorization in late February and only requires one shot.
All three proved highly effective at preventing severe illness, hospitalizations and deaths from COVID-19.
On August 23, Pfizer’s vaccine became the first to be granted full FDA approval. The Pfizer and Moderna vaccines are both made using messenger RNA, or mRNA, technology.
Traditionally, vaccines have been made from a weakened or inactivated germ that trains the immune system to fight off infection if it encounters the virus in the future. But mRNA vaccines do something different: They teach human body cells how to make a harmless piece of a protein — a “spike protein” — that’s also found on the surface of the coronavirus. After that protein piece emerges on the surface of a cell, the human immune system recognizes it and begins making antibodies for it — which offer protection if the person is exposed to the actual virus in the future.
One difference between the Pfizer and Moderna vaccines is the wait time between the two required doses: Pfizer’s are given 21 days apart, while the Moderna shots are given 28 days apart.
Johnson & Johnson took a different approach, developing what’s called a viral vector vaccine — a type that has been used for years against other diseases. It uses an altered, harmless, non-replicating version of a common cold virus, called adenovirus type 26, to introduce genetic instructions for the “spike protein.” The immune system responds by making antibodies which will protect the person if they’re infected by SARS-CoV-2, the virus that causes COVID-19, in the future.
Johnson & Johnson’s single-dose vaccine has the advantage of being stored in regular refrigerators, while the two others must be stored and transported at below-freezing temperatures.
What are the known side effects of the COVID vaccines?
In general, side effects are not uncommon with vaccines, and the COVID-19 shot is no exception. Your body’s immune reaction could include the same kinds of side effects often seen with other vaccines, including a sore arm, fatigue, fever, chills or headaches.
“This is expected,” Dr. Neeta Ogden, an internal medicine specialist and immunologist, said in an interview on CBSN.
“People should maybe think about vaccinating on weekends, for example,” she said. “You probably might need to take a day off from work. … This is predictable and I don’t think that it is alarming.”
Not everyone experiences side effects, but doctors stress that their occurrence is normal and should not discourage people from getting the shots.
Can the side effects be minimized?
The CDC offers some advice on ways to combat vaccine side effects: After vaccination, use or lightly exercise the arm that got the shot. Take Tylenol or Motrin for any pain you may have, but only after you’ve gotten the shot, not before. The CDC also recommends drinking plenty of liquids after you get either the first or second dose. If redness or tenderness increases at the vaccination site in the days following the shot, the CDC recommends that you call your doctor.
Do the COVID vaccines protect against new variants?
Health officials say the vaccines still offer strong protection against severe illness from the current variants. Recent data show hospitalization rates among unvaccinated adults were 17 times higher than among the fully vaccinated, the AP reported.
There are currently four “variants of concern“: Alpha, Beta, Gamma and Delta. Delta, which turned up in the U.S. in the spring, is more contagious and now makes up the overwhelming majority of U.S. cases — about 99% of new infections are Delta.
Experts are also keeping an eye on the Mu variant, which emerged in Colombia in January, and which has mutations suggesting it may be able to bypass existing coronavirus antibodies.
“But there isn’t a lot of clinical data to suggest that. It is mostly laboratory in vitro data,” Dr. Fauci said. “…We don’t consider it an immediate threat right now.”
Who shouldn’t get a COVID vaccine?
The CDC says people allergic to the ingredient polyethylene glycol (PEG) or polysorbate, which is similar, should not get an mRNA COVID vaccine, and anyone who has an immediate allergic reaction to the first dose should not get the second one.
People with a history of allergic reaction to a vaccine or injectable therapy for another disease should talk to their doctors, the CDC advises. It says people with food allergies do not need to avoid the vaccine.
Should you get a COVID vaccine during pregnancy?
The CDC updated its guidance to “strongly recommend” that people who are pregnant or planning to become pregnant should get vaccinated against COVID-19, citing a growing amount of data verifying the safety of the vaccines during pregnancy.
“I would say if you’re pregnant, not only is it a good idea to get the vaccine on the basis of safety, but it’s highly effective and important because you are at increased risk of bad outcomes if you get COVID,” said Surgeon General Vivek Murthy.
Many doctors say the shots are especially important because of the known risk of severe illness from COVID-19 during pregnancy.
“I recommend highly that all pregnant women be immunized, from initial discovery of the pregnancy right up to term,” Dr. Bob Lahita, professor of medicine New York Medical College and chairman of medicine St. Joseph University Hospital, said on CBSN. He said there is “no evidence” that the vaccine “has any effect on the placenta, on the fetus, on the mother. Except if one gets the infection, the COVID, and you are pregnant, you run the risk of becoming very, very sick.”
How long will COVID vaccine protection last?
Researchers and health experts say they don’t yet know for sure. On its official web FAQ, the CDC says, “We won’t know how long immunity lasts after vaccination until we have more data on how well COVID-19 vaccines work in real-world conditions.”
Moderna CEO Stephane Bancel offered a rough window: “We believe there will be protection potentially for a couple of years.”
But amid the spread of the more transmissible Delta variant and evidence that vaccine efficacy is waning somewhat, U.S. health officials began developing plans to offer booster shots to increase protection.
What’s a booster shot and when can I get one?
A “booster” refers to an extra dose for those whose immune systems responded well to the initial vaccines but might face waning efficacy as time goes on.
Pharmacies began offering third doses to fully vaccinated, immunocompromised patients in August 2021. Roughly 10 million people in the U.S. may qualify for such additional shots, with roughly 3% of Americans estimated to be immunocompromised.
Then in September, the FDA and CDC cleared the way for a much broader swath of Americans who got the Pfizer vaccine to receive a booster six months after their second dose. That includes people age 65 and over, nursing home residents, adults 50 and over with “underlying medical conditions,” and those whose jobs or living situations may put them at higher risk of exposure.
Can you still spread COVID after getting the vaccine?
People who receive a vaccine dramatically lower their chance of getting sick from the virus, though in a relatively small number of cases, people may catch what’s known as a breakthrough infection despite being vaccinated. Vaccinated people who contract the virus may have a high viral load for a period of time, even if they don’t develop symptoms. But most research indicates the vaccines help reduce its spread.
What are my risks of a breakthrough infection?
Large-scale data is still trickling in, but a London study released in early September 2021 was encouraging.
The data, gathered from December 8, 2020, through July 4, 2021, show that, of more than 1.2 million adults who got a first dose, fewer than 0.5% reported a breakthrough infection two weeks or more after getting the vaccination. Among people who got both shots, fewer than 0.2% got such an infection during the same period.
Even better: The odds of a fully vaccinated person who does catch COVID-19 needing a hospital stay shrank by more than two-thirds, compared with an unvaccinated coronavirus patient. The survey also found that the risk of patients suffering from long COVID, with symptoms lasting more than a month, were cut in half by full vaccination.
Do I still need to wear a mask after receiving a COVID vaccine?
Once you’ve gotten vaccinated it takes about two weeks for the body to develop immunity, so you’ll need to continue taking precautions like social distancing and wearing masks to reduce your risk of infection during that time.
After that, the CDC says it is safe for fully vaccinated people shed their masks in some situations, although it urged the continued use of masks indoors in areas of higher transmission as the more contagious Delta variant spread. Masks are still required for everyone in certain venues like airlines, public transit and health care facilities.
Many states have since dropped their mask mandates, although masks are still recommended for people who are not vaccinated.
What can I safely do after I am fully vaccinated?
Once people are fully vaccinated — meaning two weeks have passed after their final dose — the CDC is assuring Americans that they can can resume most activities and gather with other vaccinated people, indoors or outdoors.
Vaccinated people no longer need to self-quarantine after travel. The CDC has a more detailed list of do’s and don’ts here.
Can employers force you to get vaccinated?
Many large companies already do, and President Biden is following suit.
On September 9, 2021, Mr. Biden announced new COVID-19 vaccine requirements, which will affect roughly 100 million Americans. The new measures include a vaccine mandate for all federal workers and contractors, and a requirement that companies with over 100 employees mandate vaccines or regular testing.
The Department of Labor’s Occupational Safety and Health Administration (OSHA) is developing a rule requiring those employers to make sure their workforce is fully vaccinated or require unvaccinated workers to get a negative test at least once a week.
“Generally speaking, employers are free to require safety measures like vaccination with exceptions for certain employees,” said Aaron Goldstein, a labor and employment partner at the international law firm Dorsey & Whitney. “So the answer is likely to be yes, with an asterisk.” Many hospitals, for example, have long required staff to get vaccines, with exemptions allowed for medical or religious reasons.
American workers largely back employers making that call. More than half of those in one recent poll say they favor requiring vaccination for their workplaces.
Do I need to get vaccinated if I’ve already had COVID?
Even after you’ve gotten sick from COVID-19 and recovered, you could still get it again. So-called natural immunity varies from person to person. The vaccines, on the other hand, provide a reliably high level of protection.
That said: If you were treated with monoclonal antibodies or convalescent plasma during your illness, you should wait 90 days before getting a COVID-19 vaccine. The CDC also recommends you should talk to your doctor before proceeding.
Why are the Pfizer and Moderna vaccines two doses?
For these vaccines to reach maximum effectiveness, two doses are needed. The first injection starts building protection in the immune system. A second shot increases the amount of that protection to more than 90% against the virus.
In reporting on this issue, CBS MoneyWatch senior reporter Stephen Gandel uncovered concerns that getting only one of the two shots might actually make the pandemic worse over time.
“The concern is that if people get one shot, and not two shots, and those people get exposed to the coronavirus, the virus won’t get killed off [from] them… and the virus will figure out a way to adapt itself, and then it could spread again. Then we could have a vaccine-resistant strain of the coronavirus out there,” he explained.
Why was there a temporary “pause” on the Johnson & Johnson vaccine?
On April 13, U.S. health officials recommended a temporary “pause” in use of the Johnson & Johnson vaccine after several instances of rare blood clots were reported. Health officials identified 16 cases, mostly among women under the age of 50, three of whom died, out of more than 6.8 million people who had received doses of the Johnson & Johnson vaccine.
The pause was lifted 10 days later after a CDC panel of medical experts determined that the benefits of the vaccine outweigh the risks. A warning was added about an increased risk of rare but serious blood clots for women under 50.
The CDC and FDA said the blood clots, called cerebral venous sinus thrombosis, were seen alongside low levels of blood platelets — an unusual combination that requires specialized treatment. The agencies said the “adverse events” seem to be extremely rare, but that the pause was important so that health care providers could be made aware of how to recognize and manage such cases.
“One of the things you can take away from all of this is that when the surveillance system, the CDC and the FDA, say that something is safe, you can be sure that it’s safe,” Dr. Anthony Fauci, the nation’s top infectious diseases expert, said.
How many people need to be vaccinated before we reach herd immunity?
Experts haven’t reached a consensus on exactly what it will take for the world to achieve herd immunity — a level of widespread protection that leaves the virus few remaining targets, so outbreaks can no longer flourish.
A large majority of the population will need to be vaccinated before it can happen.
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