Dear Doctor Cockroach: I have performed regular swab tests for COVID-19, and these tests are always negative. The last one was a few days ago. I had an antibody test six weeks ago and the result was also negative, but this time my antibody test was strongly positive. I am very careful in protecting myself and there are no symptoms! I plan to buy the first dose of vaccine tomorrow. How should I do? -CW
Reply: When you have frequent negative swab tests and are asymptomatic, you are less likely to be infected with COVID-1
The result of the antibody test you sent showed a strong positive result using a very highly specific laboratory assay. Although this may be a false positive test result, I suspect that your real COVID-19 case is so mild that no symptoms were found.
You may have some immunity to another COVID-19 case, but this immunity may disappear soon. I suggest you get vaccinated on time. As long as you have no symptoms, you can safely get the vaccine. However, people who use monoclonal antibodies to treat COVID-19 should wait 90 days to get the vaccine.
Dear Doctor Cockroach: I know that someone received the first and second doses of Moderna vaccine, but didn’t get any side effects from either of them. Does this mean that the vaccines are not working, or does it mean that their systems are very powerful? Everyone is talking about side effects, but no one mentions whether you have no side effects. Please clarify because I will get the second vaccine next Saturday. -MJ
Reply: I often hear doctors and patients explain vaccine reactions, such as arm soreness and fever, as evidence that the vaccine is working. It is natural to worry that no response means that the vaccine will not work properly. But that is not the case. Even people without side effects (most people have at least a little arm soreness) can benefit from the vaccine. The Moderna vaccine is 94% effective in preventing infection.
Indeed, people with a history of COVID-19 infection are more likely to have side effects such as fever or fatigue. Therefore, I would not say that people who know no side effects necessarily have a “strong” immune system. The immune system needs to be well regulated to protect you from invaders and avoid autoimmune reactions. But this does mean that they are unlikely to have COVID-19 in the past.
Part of the danger of COVID-19 infection is the body’s immune and inflammatory response to the virus. I can speculate that those who have a very strong response to the vaccine may be the ones most likely to develop severe COVID-19 complications. In addition to speculation, vaccination is effective regardless of whether a person has side effects.
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Dr. Roach regrets not being able to answer individual letters, but will incorporate them into the column whenever possible. Readers can email questions to ToYourGoodHealth@med.cornell.edu or email to 628 Virginia Dr., Orlando, Florida 32803.
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