The top COVID-19 vaccines, safety concerns, and health updates—all in one place.

By Melissa Mills
Updated June 14, 2021

With more than 175.9 million coronavirus infections-including 33.4 million cases and over 599,781 deaths in the U.S.-since the start of the pandemic, the race to distribute a COVID-19 vaccine to Americans is on.

Progress has been made, and at a quicker pace than usual due to former President Trump's Operation Warp Speed, which aimed to deliver 300 million doses of a safe vaccine to stop SARS-CoV-2, the virus that causes COVID-19, to the American public by January 2021. Though that didn't happen, with President Biden sworn in and a national coronavirus response plan in progress, all Americans older than 12 are now eligible to get vaccinated.

To date, three vaccines have been granted emergency approval from the U.S. Food and Drug Administration (FDA) and are now being rolled out. Vaccines from Moderna and Pfizer have shown success rates of over 90 percent in real-world conditions, while Johnson & Johnson's single-shot vaccine is 72 percent effective in the U.S., though experts stress the importance of taking any vaccine that you're offered when you're eligible.

With vaccination distribution picking up, parents are wondering when, exactly, things will go back to "normal"-and what a vaccine could mean for their family. Here, the latest on vaccine development, safety concerns, what happens once you've been fully vaccinated, and everything you need to know about COVID-19 vaccines.

Vaccine Safety and Regulations

Despite the accelerated pace of Operation Warp Speed, the FDA has strict regulations that must be met before a vaccine can be distributed to the general public. To ensure the safety and effectiveness of a vaccine, it must go through three phases:

  • Phase 1: Early stage clinical trials on 20-100 healthy volunteers to test the safety profile, dose effects, and any adverse effects. If no serious side effects are discovered, the vaccine can move to phase 2.
  • Phase 2: Testing on hundreds of volunteers to determine any short-term side effects or dose effects on different categories of people. If deemed safe, the vaccine can move on to final trials.
  • Phase 3: Hundreds or thousands of volunteers are tested to evaluate the vaccine's effectiveness. This is where the FDA discovers if the vaccine prevents disease when compared to a placebo test and allows researchers to learn more about its safety and any common side effects.

Once this rigorous testing is complete and a vaccine is distributed to the public, phase 4-where the widespread effectiveness or long-term effects are tested on a greater population-will begin. To be considered effective, the FDA says that a vaccine should protect 50 percent of recipients.

"This unprecedented period has called for innovation, speed, and efficiency in vaccine production," says Mobola Kukoyi, M.D., MPH, an emergency physician at Carle Foundation Hospital in Urbana, Illinois who has seen both pediatric and adult COVID-19 cases in the emergency room. "Understandably, this comes with a concern for safety. However, given the different regulatory checkpoints in the phases outlined above, a product is only approved if it meets specific guidelines. My advice to all would be to follow the science."

Vaccine Front-Runners

With more dozens of vaccines under development worldwide, a handful have shown promise. These are the ones to know about:

1. Pfizer

As of December 11, Pfizer-working with German company BioNTech and Chinese drugmaker Fosun Pharma-has been approved for use in the U.S. following a final data analysis showing its vaccine is 95 percent effective in preventing infection.

Early clinical trials for the vaccine tested a more diverse group, including children as young as 12 years old, as well as people with HIV, Hepatitis C, and Hepatitis B. After receiving emergency FDA approval, Pfizer is now including children between 6 months and 12 years in trials.

Pfizer announced that its vaccine is 100 percent effective in preventing illness in 12- to 15-year-olds and, on May 10, received emergency use authorization for that group. Pfizer also hopes to extend emergency use authorization to kids ages 5 to 11 in September, according to The New York Times, and kids as young as 6 months old may get the go-ahead shortly after that.

2. Moderna

Partnering with the National Institute of Allergy and Infectious Diseases (NAIAD), Moderna, a biotech company in Cambridge, Massachusetts, created the first vaccine to reach phase 3 testing. On November 30, Moderna announced that results show its two-dose vaccine is 94.1 percent effective. As of December 18, Moderna became the second drugmaker to receive approval from the FDA for rollout for people ages 18 and up.

After receiving this emergency approval, Moderna started enrolling kids 12 and up in new trials and is now including children between 6 months and 12 years old. They recently announced that its vaccine is highly effective in adolescents ages 12 to 17, and they plan to apply for emergency use authorization for this age group in June. Younger children may be eligible to get the Moderna vaccine later this year.

3. Johnson & Johnson

With $500 million in backing from Operation Warp Speed, Johnson & Johnson's COVID-19 vaccine launched its phase 3 trials in September, though trials were temporarily paused in mid-October after an "unexplained illness" in one of the volunteers.

Now Johnson & Johnson-whose single-dose vaccine is 72 percent effective in protecting against COVID-19 in the U.S., but is even more effective in preventing severe disease and may reduce spread of the virus-has been approved for emergency use authorization from the FDA.

On April 13, use of Johnson & Johnson's COVID-19 vaccine was paused after six women developed blood clots. Nearly seven million people had received the vaccine in the U.S. at that time, and the FDA and CDC called for this pause out of an abundance of caution. After looking into the blood clot cases-which ended up totaling 15 instances-the vaccine has been restarted with a warning label about the rare clotting disorder. All of the cases occurred in women; the majority (13 cases) were in women between 18 and 49 years old, says The New York Times.

4. AstraZeneca

In collaboration with the United Kingdom's University of Oxford, British-Swedish pharmaceutical giant AstraZeneca has been awarded $1.2 billion to get 300 million doses of its vaccine contender ready for the U.S.

AstraZeneca said on March 22 that it would apply for emergency use authorization by the FDA in the coming weeks, but new concerns over outdated information included with the vaccine's results may cause setbacks.

5. Novavax

After a successful round of safe early clinical trials, Novavax, a Maryland-based company, has another vaccine to watch. Preliminary studies on monkeys and humans showed the production of virus antibodies, as well as killer T-cells, which can kill cells with the virus. Novavax has already begun phase 3 testing in the U.S..


Is the testing moving too fast?

"The speed which this vaccine will be brought to market is unprecedented," says Kevin Kathrotia, M.D., neonatologist and COO of Millennium Neonatology in Charlotte, North Carolina who has cared for babies whose mothers have tested positive for COVID-19. "This is a testament to the herculean effort of scientists and doctors at multiple companies, research facilities, and some of the world's greatest universities." 

And while things are moving faster than usual-it usually takes years to develop a vaccine, and COVID-19 vaccines are set to be distributed within 24 hours of FDA approval-Dr. Kathrotia says that we should trust the clinical trial process and the fact that a drug brought to market is safe and works. "Having said that, I would wait to go completely back to normal until we see flattening and/or virtual elimination of the virus, which can lag full scale implementation of a vaccine."  

Who should get a COVID-19 vaccine?

After undergoing a strategic rollout to the public-with doses available first to health care workers, high-risk adults, and residents of long-term care facilities-states began broadening eligibility. Now all American age 12 and up are eligible to receive a COVID-19 vaccine. The hope is for all Americans to be vaccinated in 2021.

Is it safe for children?

Vaccines that have been approved by the FDA should be safe, but many COVID-19 vaccine early clinical trials excluded children. After receiving emergency FDA approval, though, Pfizer and Moderna started enrolling kids 12 and up in new trials, and both are now including children between 6 months and 12 years.

On March 31, Pfizer announced that its vaccine is 100 percent effective in preventing illness in young teens and, on May 10, received emergency use authorization for 12- to 15-year-olds. Pfizer also plans to apply for emergency use authorization for kids ages 5 to 11 in September, as well as younger children shortly after that.

Along those lines, Moderna announced that two doses of its vaccine are 100 percent effective in children ages 12 to 17, and one dose is 93 percent effective. No major side effects were reported in clinical trials.

We'll know more about when children should receive the COVID-19 vaccine in the coming weeks and months and as more testing is done. That said, the CDC and AAP strongly recommend that all children continue to receive their routine vaccinations during the pandemic.

Note: The CDC has reported rare cases of myocarditis and pericarditis (inflammation of the heart) in people under 30 years old who received Pfizer of Moderna. Most cases-which come with symptoms like heart palpitations, chest pain, and shortness of breath-have occurred in males after their second dose, and they usually resolve with treatment. The CDC is investigating further, but they still recommend that everyone 12 and up get vaccinated.

Is it safe for pregnant women?

Researchers are still studying how COVID-19 impacts pregnant women and fetuses, and pregnant women are finally being included in vaccine clinical trials. Experts expect results in the next few months.

As of now, the American College of Obstetricians and Gynecologists recommends that pregnant women receive the vaccine, while the CDC suggests pregnant people discuss with their health care provider to make an informed decision.

"While pregnancy puts women at higher risk of severe COVID-19, very little data are available to assess vaccine safety in pregnancy," said the World Health Organization in updated guidance. "Nevertheless, based on what we know about this kind of vaccine, we don't have any specific reason to believe there will be specific risks that would outweigh the benefits of vaccination for pregnant women."

So what does this mean, exactly? There's simply not enough data yet on how COVID-19 vaccines affect pregnant people, though Dr. Fauci says there have been "no red flags" when it comes to the 20,000 pregnant women who had already been vaccinated as of mid-February.

More good news: A baby in Florida and a baby in Colorado have been born with COVID antibodies after their mothers received the vaccine during pregnancy. Early studies also point to protective antibodies being passed through the breast milk of those who have been vaccinated.

Your best bet? To discuss options with your doctor.

Is it safe for people with allergies?

Early Pfizer vaccine distribution in the U.K. sparked warnings that those with severe allergies should not receive the vaccine, but Americans with allergies have received the OK to get it-though they'll have to discuss with their doctors first and be monitored following vaccination.

"People that do report those types of anaphylactic reactions to other vaccines or injectables - they can still get the vaccine, but they should be counseled about the unknown risks of developing a severe allergic reaction and balance these risks against the benefit of vaccination," said Sarah Mbaeyi, a medical officer with the CDC's National Center for Immunization and Respiratory Diseases.

If you or your child have a history of allergic reactions, you should speak with your doctor before getting vaccinated.

How will I know if my family should get the COVID-19 vaccine?

"We understand that some people may be concerned about getting vaccinated once a COVID-19 vaccine is available in the United States," said the CDC. "While these vaccines are being developed as quickly as possible, routine processes and procedures remain in place to ensure the safety of any vaccine that is authorized or approved for use. Safety is a top priority, and there are many reasons to get vaccinated."

According to the CDC, getting the coronavirus vaccine may help you from becoming seriously ill if you do get COVID-19, but it will also help those around you from becoming sick.

Health experts agree that families should let the vaccine data speak for itself once testing is complete. The FDA and government officials will share ongoing vaccination guidance, but you should check with local health officials and your doctor about your family's vaccine plan.

OK, I'm vaccinated-now what?

Finally some good news: New guidance from the CDC suggests that people who have been fully vaccinated can start to safely enjoy some of the things they've put on hold during the pandemic.

You're considered fully vaccinated two weeks after receiving the second dose of the Pfizer or Moderna vaccines or two weeks after receiving the single shot from Johnson & Johnson. Here's what you can do once that happens:

  • Skip wearing masks and social distancing in any situation, indoors or outdoors, except "where required by federal, state, local, tribal, or territorial laws, rules and regulations, including local business and workplace guidance," says the CDC. You'll still need to wear masks on public transportation (like trains, buses, and planes) and in health care settings.
  • Resume domestic travel. You also don't need to get a COVID-19 test (unless required by your destination) or self-quarantine before or after travel.
  • Travel internationally without testing, unless your destination requires it. That said, "fully vaccinated air travelers coming to the United States from abroad, including U.S. citizens, are still required to have a negative SARS-CoV-2 viral test result or documentation of recovery from COVID-19 before they board a flight to the United States," says the CDC.
  • Refrain from self-quarantine after returning from international travel.
  • Skip out on quarantining or getting tested if you've been exposed to someone who has COVID-19-unless you start to exhibit symptoms.
  • Stop routine screening testing.

It's also very possible that fully vaccinated individuals will need to receive booster shots within 12 months, and another yearly dose after that (sort of like with the flu shot), but we'll know more in the coming weeks and months.