-by Dr. Alan Laird, Chief Medical Officer
Much like the famous ride of Paul Revere announced the coming of the British army, the news channels have reported much about the imminent arrival of vaccines for Covid-19. But instead of a single question, (by land or by sea), there are a lot questions about the vaccines themselves. There is still much we do not know about Covid-19, let alone the vaccines developed to fight it. I will attempt to share some of what I have learned. But in this age of instant news, it is possible things will have changed by the time you read this.
First of all, a bit of disclosure. I believe most vaccines have provided a world of good to mankind. Please consider the following. In the 1920s there were one hundred thousand to two hundred thousand cases of diphtheria a year in the United States. Of those children that were infected, ten to fifteen percent died. During the 1930s and 1940s, diphtheria was virtually eliminated due to routine childhood vaccination with diphtheria. No doubt, improved standard of living has also helped with the ridding of this disease. Compare those numbers to 2015 – 2018 when only 4 total cases over those 3 years were report in the US. That is an impressive victory over a disease that killed so many each year 100 years ago. So vaccines do work and can improve lives. But the Covid vaccines have been developed very rapidly. And we have heard a lot about them. Not the usual way we hear about things happening. Let’s take a closer look.
It often takes 10-15 years to get a vaccine ready for general use. A lot of that time is spent in exploratory and preclinical stages. These stages involve deciding if it is feasible to make the vaccine and then animal testing before any human trials. We have benefited here from the warning bells of other coronavirus out breaks in 2003 (SARS) and 2012 (MERS). A number of companies and scientists were betting the next pandemic would be a coronavirus similar to those. So a lot of the “pre-work” was already done. The FDA has also worked more closely with those companies developing the vaccines to allow some overlapping of trials and safety testing more rapidly. This has allowed completing some steps simultaneously. Previously a step or trial would have to be completed fully and then submitted for review. This added several months before the next step could even be organized, let alone started. Oversight has not been lax, but has been more involved and expedited.
Currently there are at least 11 vaccines in large scale trials. These trials have as many, if not more individuals in them than previous vaccine studies. We have heard preliminary results for two of the manufacturers indicating their vaccines were 90-95% effective at preventing the Covid-19 disease. There is a third close to releasing data. Some companies have been given permission to go ahead and produce a large supply of the vaccine, prior to being authorized to distribute and use it. To date, no vaccine has gained full approval.
So if the vaccines continue to show good results (the FDA says the vaccine must be at least 50% effective, the same number as the overall average of the flu vaccine) and continues to appear to be safe (the FDA says it must have 2 months for safety data since 90% of adverse reactions show up in the first 60 days of a vaccine use), we could see a vaccine approved for use late this year or early next year.
When will it be available? Since the companies are already allowd to produce supplies, it will likely be very rapidly after approval. States and health systems have already developed and are refining steps and staging for vaccination. Logistics are being worked out. It will most likely be made available first to healthcare workers on the frontlines and those with special risks for severe Covid-19 disease. During that time, intense monitoring of those who get the vaccine will take place. It will probably be several months before it is generally available. And that will be added time to see side effects or lack of efficacy.
So, how long will the vaccine be good for? That remains to be seen. It appears most of the front runners require at least two shots several weeks apart to give full protection.
What about children? The vaccine will most like be approved first for adults since most children do not get as sick with Covid-19. Whether adult results can be extrapolated to children or there will need to be separate trials done for children, remains unknown.
What about pregnancy? We do not know what the recommendations will be for pregnancy. This population is typically not part of the trial groups and information is only gleaned later where women received a vaccine not realizing they are pregnant.
Are these vaccines similar to those previously produced (like MMR or tetanus)? Some are, but the front runners are not. They are using new technology and it is part of the reason they could be developed so quickly. The science behind them is sound, but we do not currently use a vaccine that produces immunity the same way the top 3 candidates do.
Should you get the vaccine if you had Covid-19? We don’t yet know.
Do you have to have a period of time between other vaccines like the flu shot and the Covid-19 vaccine? We don’t know yet.
For some, the question about the use of fetal cells will be important. Information on the use of fetal cell lines in the vaccine development can be found at: Coronavirus – Christian Medical & Dental Associations (https://cmda.org/coronavirus). They also have a general vaccine statement available discussing the use of fetal tissue.
So there are still a lot of unanswered questions about the Covid-19 vaccines and even the Covid-19 disease. But one thing that is not in question, is their arrival. The vaccines are coming!