A: The earliest we can expect vaccines to be available is January, and they will be available to the most vulnerable populations first, with general public availability following by Spring 2021.
But even with an effective vaccine, some social distancing measures are expected to be in place at least until the end of 2021, with a sense of normalcy returning gradually.
Through Operation Warp Speed, the United States has supported 6 vaccine candidates by funding either clinical trials, increases in manufacturing and distribution capabilities, or both. The vaccine candidates that are furthest along in the trial process are being developed by Moderna and Pfizer. Both of these companies have projected readouts–or study results–by the end of November, and plan to file for approval with the FDA soon after.
If Moderna and Pfizer can show that their new vaccine is safe and effective, FDA may give them regulatory approval, and the first vaccines may be distributed by January 2021. The most vulnerable populations will be offered the vaccine first including front line healthcare workers, essential workers that are working on critical infrastructure, those with underlying medical conditions, and older people. After that, there will likely be phases of eligibility for who would get the vaccine next. For example, a second eligibility phase may include people living in group quarters and K12 teachers. Depending on supplies, the vaccine could be made available to the general public perhaps by spring of 2021.
Even with an effective vaccine, Director of NIH’s infectious disease division, Dr. Anthony Fauci, thinks we will still have social distancing and mask-wearing in place at least until the end of 2021. We will have a gradual return to a sense of normalcy as we slowly re-open and expand our ability to congregate.
The current phase III vaccine clinical trials do not include children or pregnant mothers. A vaccine has to be shown as safe in adults before it can be tested in these special populations. Vaccine makers will have to first do a small trial to ensure safety and effectiveness, and then expand to a larger phase III trial or show comparison to the adult trial for larger scale safety and effectiveness in children and pregnant women.
Follow up Question 1: But what if the first trial fails?!
Do not despair! The current vaccines show many similarities and some key differences that may mean some work, even if the first efforts do not.
All of the vaccines are focusing on the spike protein of SARS-CoV-2. This protein enables the virus to enter the cells in your body and make multiple copies of itself. By targeting this protein, the vaccine will prime your immune system to recognize the spike protein and make antibodies against it. The antibodies will then recognize and stop the virus from entering cells when you encounter it “in the wild” later on.
The Moderna and Pfizer vaccines target the spike protein in slightly different ways. For example Moderna is using mRNA vaccine, a genetic sequence that encodes the spike protein. Pfizer is also using mRNA enclosed in tiny particles.
The other vaccines in development are using very different technologies. Both Janssen and Astrazeneca are using strains of adenoviruses–which causes the common cold–that they have altered to express the coronavirus spike protein and to not be able to grow and multiply itself. The idea is that the adenovirus will activate the immune system and prime it to recognize the spike protein on SARS-CoV-2.
The two other vaccines that are further behind are NovaVax and Sanofi/GSK. These companies are using recombinant spike proteins together with an adjuvant to trigger the immune system. An adjuvant is something that causes your immune system to get excited–like a tickle.
Even if the first vaccine trials do not work, we still have other trials underway that target the spike protein and activate the immune system in other ways.
Follow up Question 2: Will the virus evolve so that the vaccine is no longer effective?
The coronavirus is evolving but scientists are hopeful that we can have a vaccine that is effective and distributed before the coronavirus changes significantly. Importantly, scientists think that the current vaccines may still be effective given the virus’s evolution so far.
Follow up Question 3: Is this a one shot and done deal? How long will vaccine immunity last?
Most of the vaccines in development require 2 injections. Janssen is testing a one shot vaccine. Scientists will have to follow patients to see how long immunity lasts. At this point it is unknown but scientists are hopeful that immunity may last at least a year or two.
Within one year of the virus being discovered, we have multiple vaccine candidates in late-stage clinical trials. We may know if the first vaccines are effective by the end of November and possibly first distributed in January.
Vaccines are moving forward at an unprecedented pace.
At the same time, when we do find an effective vaccine it will take time for a vaccine to be distributed. Operation Warp Speed has helped different companies start to manufacture their vaccines already so that we have many doses available immediately if the vaccine proves to be safe and prevents COVID-19. While we are distributing the vaccine, everyone should be mentally prepared to continue with the SMART guidelines in place until we do reach herd immunity through vaccination.