The Janssen vaccine for COVID-19 (manufactured by Johnson and Johnson, and just approved for emergency use) is going to be a great improvement in the country’s response to the pandemic. It only requires a single dose to offer good protection, and is much easier to transport and administer because it can be stored long term at normal refrigerator temperatures. (No worries about that last dose in a vial going bad in a hurry.) Those differences will greatly reduce the logistical overhead of mass vaccination. As production of the vaccine ramps up, it will become especially important in reaching smaller, more distant communities.
Similar to the Moderna and Pfizer vaccines, it doesn’t actually contain the material that your body is getting trained to recognize, the coronavirus spike protein. All three vaccines are designed to transport an RNA sequence into a small number of cells in your body. Those cells then produce and secrete a portion of the spike protein. The sudden presence of the foreign spike protein is what triggers your immune system to action, and teaches it what kind of antibody or T-cell response to use when confronted with actual coronavirus in the future. The Pfizer and Moderna vaccines contain bare mRNA, encapsulated in small globules of fat, which are designed so that they have a tendency to fuse with your cells and inject the mRNA into them. The Janssen vaccine uses a different vector to carry the RNA, an adenovirus which normally causes the common cold, but which has been modified so that it cannot replicate or cause illness.
Side effects will vary from person to person. I received the single dose vaccine on Thursday (March 4), and so far have experienced only mild symptoms. There is some injection site soreness, which has been causing tightness in neck and shoulder muscles. I have been able to manage the soreness and tightness with exercise and relaxation techniques (tai chi), but I imagine that people who don’t know what exercises to do could get a very stiff neck and a corresponding headache. I felt a little muzzy-headed for a few hours that evening, but after having slept, I feel much clearer. I have a very slightly elevated body temperature, about half a degree higher than normal, which made sleeping a little bit uncomfortable because I couldn’t settle on which blanket to use.
This vaccine provides moderate protection after about two weeks, and better protection after about four weeks. That means that even if confronted with new variants, such as the ones from South Africa or New York, the chances of illness are reduced, and the chances of serious illness or hospitalization are greatly reduced. It isn’t a free pass, because new variants that are already circulating in the Houston area may be able to partially evade vaccine protection, so I will be continuing to wear medical grade masks and eye protection in the clinic, and ask that patients continue to wear masks during treatment whenever possible.
When do we get back to normal?
Scenario 1: When case loads drop to the point that contact tracing efforts by public health departments are able to quarantine all chains of transmission in our country, or
Scenario 2: When everyone who wants the vaccine has been fully vaccinated, including future booster shots that cover new variants.
If we all pitch in and keep doing the right things, I am optimistic that we can see the situation improve rapidly.