When will vaccine be available?

The FDA approved the Pfizer vaccine for ages 16 and older on Dec. 11, and shipments were en route to hospitals and other health centers in all 50 states. The FDA approved the Moderna vaccine for ages 18 and up on Dec. 18. Initially, vaccine demand will exceed supply. The good thing is these platforms allow vaccines to be made very quickly. Both Pfizer and Moderna expect to be able to make over 1 billion doses by the end of 2021.

Who will get the first doses of the vaccine?

The vaccine will go first to front-line healthcare workers – along with people who live in long-term health care facilities – because those groups are at highest risk. That should be followed by teachers, people with other high-risk conditions and then everybody else. However, by March to April we should have sufficient vaccine for everyone in the approved age group who wants to be vaccinated. It will be ramped up quickly. By the start of the next school year, we could have vaccines for adolescents and even younger children.

COVID-19 vaccine vials.

If kids don’t get that sick from COVID, why do they need to get vaccinated?

More than 1.5 million kids in the United States have been infected, and hundreds to thousands of them have been hospitalized. At least 150 previously healthy kids have died of COVID. The vaccine is important for the health and safety of children, but also to prevent them from spreading the disease to adults such as parents, grandparents and teachers. Vaccines are going to be critical to get rid of the pandemic. It’s much safer to get the vaccine than to contract the disease.

Which COVID vaccines have been tested in clinical trials at Cincinnati Children’s?

Cincinnati Children’s has helped conduct the clinical trials for the Pfizer vaccine candidate in ages 12-15, 16-17 and adults; as well as the AstraZeneca vaccine candidate in adults.

Can I get COVID-19 from the vaccine? 

No. The vaccines prompt our body to make a piece of the virus called a spike protein. The body then makes antibodies to the spike protein designed to protect people against COVID-19 should they be exposed to the virus. Because the vaccine does not contain the whole virus, it is impossible to get COVID-19 by receiving it. 

How do COVID vaccines work?

The spike protein on the outside of COVID-19 is what allows the virus to attach to our cells and start an infection. If your body can prevent the spike protein from attaching to our cells, then the virus can’t make us sick. So, the goal of all the COVID-19 vaccines is to make antibodies against the spike protein. The Pfizer and Moderna vaccines use pure spike gene mRNA to get our body to start the immune response. AstraZeneca and Janssen vaccines use a common virus called adenovirus to bring the spike protein gene into our body and start the immune response.

Do COVID vaccines alter the DNA of the person who receives the vaccine?

The vaccines DO NOT change your DNA. For all four COVID vaccines (Pfizer, Moderna, AstraZeneca and Janssen), the main function is to bring messenger RNA, also known as mRNA, into a part of our cell called the cytoplasm. The genetic material known as DNA is in the nucleus of our cells. There is a wall around the nucleus that prevents RNA from getting into the nucleus. Thus, the vaccines have no ability to change our DNA. Also, the mRNA used in these vaccines only lasts in our cytoplasm for a few days, and then our body destroys it. So, the mRNA does its job of having our body make a harmless piece of the spike protein in COVID-19, and then our body starts an immune response against the spike protein. This immune response is what protects us against being infected by COVID-19.

Do any of the vaccines use human stem cells?

None of the vaccines contain human cells. The Pfizer and Moderna vaccines are pure mRNA that was made in the lab. This process does not use any cells at all. The AstraZeneca and Janssen vaccines use an adenovirus to bring the spike protein gene to our cells. Viruses need to grow in cells. After the adenovirus used in the AstraZeneca and Janssen vaccines are grown, the virus is collected from the cells and purified. So there ONLY is virus, NO human cells, in the AstraZeneca and Janssen vaccine. The initial cell line for the AstraZeneca vaccine came from human embryonic kidney cells. However, those cells were obtained over 60 years ago. There are NO human cells in the finished product of either the AstraZeneca or Janssen vaccine.

Did the clinical trials use placebo? And if so, what was the placebo substance?

Yes, the Pfizer studies use a salt-water solution placebo to be able to tell if the vaccine is effective. Once the study question is answered, the blind will be broken (we will look to see who received vaccine and who received placebo). Those who received placebo will be offered vaccine. Designing the study in this manner will allow us to answer the study question and have the study be as safe as possible. The AstraZeneca trial also uses a saline placebo.

How were these vaccines developed and approved so quickly?

Things have moved faster than normal, but we have done everything correctly. The FDA was able to approve an Emergency Use Authorization for Pfizer based on its good safety and efficacy profile. We have been very careful in monitoring safety and have taken no short cuts in evaluating the vaccines at Cincinnati Children’s. Almost 40,000 people enrolled in Pfizer nationwide, over 30,000 enrolled in Moderna and close to 30,000 for both Janssen and AstraZeneca. Thus, we will have a lot of safety data before the other vaccines are licensed. It will be important, though, that opinion leaders in all our communities understand about the vaccines and the need for everyone to receive vaccine. The opinion leaders can help share the word with their communities.

Are the vaccines safe?

Both the mRNA and adenoviral vectored vaccines will likely reach licensure as all four in development now have shown a good safety and efficacy profile. Both the mRNA vaccine platform (Pfizer and Moderna) and the adenoviral vector vaccine platform (AstraZeneca and Janssen) have the same goal of putting the spike protein on the surface of our cells so our body then can start the immune response. Think of the adenoviral vector vaccine as a mechanism to bring the spike protein gene to the cell. The adenovirus has been made so it cannot grow in us, so we don’t think of it is a typical “live virus” vaccine.

Do the vaccines have side effects? 

Almost 90 percent of people who have received the COVID-19 vaccines have had no side effects. Of the other 10 percent, participants reported having headaches, fever and injection-site pain for a few days after receiving it, all of which can be addressed by taking ibuprofen. But these side effects are temporary and are a sign that the vaccine is working. While we would prefer that no one who received the vaccine had any side effects, we think the benefit of protection against a potentially lethal virus FAR outweighs the possible risks of the vaccine. 

Should immunocompromised individuals get vaccinated?

These vaccines don’t contain a live virus, and the vaccines cannot give you COVID. So even if you are immunocompromised, there is no reason to not get vaccinated. If a vaccine used a live virus, sometimes there would be restrictions for immunocompromised people. But these are not live-virus vaccines.

How is the vaccine administered? 

The vaccine is administered via injection in two doses, with the second dose being given three to four weeks after the first. It is important to get both doses. 

If I get the first dose of one vaccine, does it matter if I get a second dose of a vaccine from a different company? 

To be on the safe side, we likely will recommend getting the same vaccine for both doses, if possible. For people who have participated in vaccine trials, there will be provisions to ensure all the participants receive COVID-19 vaccine. The exact method is still being worked out. Once plans are finalized, all the participants will be notified.

How long will immunity last after I take the vaccine? 

At this time, we don’t know. Some vaccines, such as those against hepatitis and the measles, seem to last a lifetime in most people. Others, like the flu vaccine, must be given annually. The Pfizer vaccine is designed to attack the spike protein. We believe the spike protein is critical for the virus to cause an infection. Thus, it may be that even though the virus changes in other areas, it has to keep the spike protein “as is.” If that turns out to be true, it is possible that a vaccination could last many years. However, more research is needed to know if this will be the case. 

How many people need to receive the vaccine before it would be safe to go back to normal life? 

We would need at least 70 percent of the population to get the vaccine to achieve herd immunity. This would allow us to go back to being able to eat at restaurants, go to movie theaters and gather with family and friends indoors — the usual activities we enjoyed before COVID. 

What are the demographics of participants in COVID vaccine trials at Cincinnati Children’s?

About 50% of our participants are 60 or older. About 20% of participants are self-identified as African-American or Hispanic. The racial distribution is equivalent to our demographics in Cincinnati. We have enrolled across the socio-economic spectrum.

Do people who are vaccinated early on, including through the trials, have to continue to take precautions such as wearing a mask and social distancing?

Yes. All of the clinical trials include some people who received vaccine and others who received placebo. The trials still are “blinded,” so neither the participants nor study team knows to which group they were randomized. Because of that, people in the trials should assume they received placebo and continue to take precautions. Right now, the efficacy of the vaccine is based on seven days after the second dose. So from the time you got the first inoculation with vaccine, it would be about another month before you could count on immunity. But people should continue to wear masks until a significant portion of the rest of the population gets vaccinated. Masks can help prevent up to 85% of COVID infections.

The overall fatality rate for COVID is 2 percent to 3 percent. Why not just open everything up and take our chances with getting infected, since most people will survive anyway? 

Taking this route would be one way of getting us to herd immunity, but it would come with a hefty price. While a 2 percent to 3 percent fatality rate may sound small, if you apply it to the entire population, you are talking about 5 million to 10 million people who would die from COVID. Along with overwhelming our healthcare systems, which are already strained, and decimating the economy, it would result in a lot of human suffering and exact a huge emotional toll on families faced with losing loved ones. The goal of science is to get us to immunity with a lot less morbidity and mortality.   

Reviewed by Robert Frenck Jr., MD, and Hector Wong, MD