I have been vaccinated for Covid. Now what?

 Congratulations. You have taken a step towards being protected and towards the threshold of living without the fear of Covid-19 affliction. But you are not there yet.

 An elder of my family recently wrote to me stating that he had himself tested for antibodies to the coronavirus a month after having been fully vaccinated. The result came back as disappointingly low level of antibodies.

 So he asked: What am I supposed to do now?

 Nothing different that you have been doing all along, I said.  The same standard operating principals: Maintain social distance, cover face and nose and hand hygiene. Since you don’t have a strong level of antibodies, you are not fully protected. Antibody testing after vaccination is not recommended by the CDC at this time.

 He was not happy to hear this but recognized that Covid-19 being a new infection and a pandemic, there was no one straight answer.

 No single action offers 100% protection, whereas the outcome of doing everything is cumulative and takes us towards the elusive goal of 100%, I said.

This conversation led to a deeper scientific discussion since he was curious.

The production of antibodies depends on myriad factors. The main factor is the status of one’s own immune system, the other being efficacy of the vaccine. Age is another factor. The elderly are less likely to develop strong immunity.

The immune system is complex and has multiple interactive components. B cells, a variety of T cells, dendritic cells and macrophages are just to name a few. The system works like a soccer team. The information about the foreign invader is passed on from one component to the other and to the other, till the job is done. A weakness or impairment of any component can lead to inadequate response.

The immune response also depends on the quality and efficacy of the vaccine. As we have learnt from the news sources, not all of the current vaccines offer the same degree of protection. Some researchers have also questioned the accuracy of the data from the clinical trials carried out in China and Russia, since these have not been widely shared.

A vaccine that unfortunately may have been degraded during storage or transportation, may not end up being as effective as it should have been.

If one is immunosuppressed, the body may respond with weak or no immunity at all. This is true of individuals who have cancer, immune disorders or are on immunosuppressive drugs.

The other issue to keep in mind is the quality control and accuracy of the antibody tests.  These are performed in commercial labs and each laboratory may be performing a different type of test. The tests which determine the ability of vaccinated individuals’ blood to block the growth of virus in a culture tube, such as the VNT (virus neutralizing test) are more accurate. Such tests take about 5 days to be completed.

The antibody tests that deliver results in minutes or hours, use antibody binding technique.  

So, coming back to the question: I have been vaccinated. Now what?

The current guidance is to continue all the precautions as if one has not been vaccinated. It is counterintuitive to do so since one thinks that vaccination will prevent us from getting sick with Covid and may also help reduce our ability to transmit it to others. A vaccinated person can in fact be contagious, even if he/she has a strong antibody level. So in the company of unvaccinated people, or elderly, act as if you are contagious: wear mask and social distance to prevent the spread.

But since this is  new infection and the medical professionals yet do not know all about this disease, the safe bet is to do everything right. Get vaccinated, wear the mask, keep social distance and use good hygiene.

It is hoped that like the influenza, once there is adequate herd immunity, the rate of infection will decrease to a handful and by that time, we will also be able to manage the disease and its side effects better.

Some commentators have said that even a weak immune response is better than having no immunity.  The data on the severity of Covid illness and the level of antibodies, is still not here.

Another question that has been popping up is the role of a booster vaccine, down the road. As of now, a successful vaccination should offer protection for 3-4 months. The clinical trials to answer the booster question have already been initiated.