by Dr. Steven Graff, Director of Clinical Services, TCRC
It is hoped that there will be a vaccine for COVID-19 approved for use in early to mid-2021, if not sooner. At this time there are 52 vaccines in clinical trials around the world in humans presently, and 86 others in preclinical trials with animals, but there are many questions about the vaccine(s). At this point in time 10 of the 52 have reached the final stages of testing. Vaccines will vary in the number of inoculations needed, the speed of immune response they generate, acceptable side effects, the cost of the vaccine, how to store it safely, etc. Since it is not possible for everyone to get the vaccine at the same time, recommendations for groups with priority will be needed. There may be recommendations from the CDC but ultimately it could be up to state governments.
First off, the CDC needs to decide on the age group that should get it – most likely adults – as the only group being tested is adults, but what about vaccinating children? Secondly what groups of adults should have priority since supplies, at least initially, will not be sufficient for everyone? Questions still persist about the possibility of side effects. As of today there are seven experimental COVID-19 vaccines in the USA that have advanced to phase 3 testing. The FDA and CDC have set a minimum of 2 months duration after vaccination to evaluate safety of such trials. So if a vaccine maker got approval today this means that it would not be until January that their batch of vaccines will have met the minimum time before re-evaluation for final approval, and that isn’t happening until Phase 3 results are concluded to be overall ready. However Pfizer announced Monday that its vaccine data shows its vaccine has 90% efficacy and is likely to ask the FDA later this month for emergency authorization to distribute its vaccine. If this happens, then we might see limited doses become available by the end of the year. Storage and cost are critical issues. The roll out of the chicken pox vaccine 16 years ago was marred by improper storage of the vaccine by many physicians, which resulted in the vaccine being useless when finally administered. The Pfizer vaccine (most likely to be released first) makes this effort even more complex. The vaccine, requires storage at minus 70 degrees Celsius (minus 94 Fahrenheit), which is a much lower temperature than the freezers almost all physicians and pharmacies use. Additionally, the Pfizer vaccine requires two doses spaced three weeks apart. Administration of the vaccine is also important. On the topic of priority, consensus is that healthcare workers will be vaccinated in the first stage of distribution. Then will come first responders (firefighters, law enforcement, EMT). The next group might include people of all ages who have two or more comorbidities that put them at significantly higher risk for COVID-19 or death (heart disease, diabetes, kidney disease, morbid obesity, and age over 65) as well as older adults living in congregate or overcrowded settings. Another concern the CDC has is women who are pregnant or breastfeeding. They will be given priority over older women and men. Available data indicate potentially increased risks for severe maternal illness and preterm birth associated with COVID-19 infection. Some have advocated workers in essential businesses (pharmacies, groceries, farm workers, etc.) be next in line.
Once we start distributing a vaccine it will take many months to get to the point where we have herd immunity. It will take at least 60% of the population to be either infected-recovered or vaccinated for some herd immunity and that may not be accomplished until late 2021 or even into 2022. Some people may choose to hold off until vaccinations have been used for a while.
In short, a vaccination is on the way and will be available within months. Until then, keep wearing your mask, washing your hands, and social distancing. While we’re making good progress with developing promising vaccines, this virus isn’t going away very soon.
QUICK FACTs on COVID-19: A study of more than 55,000 confirmed cases of COVID-19 reported the most common order of symptoms was 1. fever, 2. cough, 3. muscle pain, 4. nausea/vomiting, and 5. diarrhea. Risk factors for severe COVID-19, regardless of age, include the following: Obesity, Chronic kidney disease, Chronic obstructive pulmonary disease (COPD), Immunocompromised state due to solid organ transplant, Serious heart conditions (e.g., heart failure, coronary artery disease, cardiomyopathies), Sickle cell disease, Type 1 diabetes mellitus, Type 2 diabetes mellitus.