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Ask the Doctor: Reactions and Side-Effects to the COVID-19 Booster Shot.

This content was current as of the date it was released. In science and medicine, information is constantly changing and may become out-of-date as new data emerge.


My question relates to certain reactions/side-effects to the Booster shot received 8/21/2021, not experienced previously with Pfizer doses 1 and 2 received in January/February 2021:

Extreme fatigue, lack of energy, appetite, feeling out of sorts was anticipated.

Not anticipated included two days of fluctuating temperature – normal to hot, feeling feverish or hot, sweaty most of the time, yet 97.5 by thermometer. To me, akin to post-menopausal hot flashes.

I realize we all continue to learn more about the vaccines, but wonder, are we maxed out with the MRNA vaccines at dose three?   Are the symptoms described above perhaps indicative of this and how do we plan proactively in the future?

Answer: There are some data now indicating that having symptoms after the COVID-19 vaccines can equate to a more robust antibody response. We hope that is the case for you! The term “booster” is a bit misleading since frequent doses (such as annually) are unlikely to be necessary. It is more likely that this third dose will represent a three-dose vaccination series that will hopefully provide long-lasting immune protection. This is similar to what has long been done with certain childhood vaccinations, such as hepatitis B. New variants that are not as well covered by the present vaccines may necessitate reassessing the need for future doses of the same or newly modified vaccines.

I think we all hope that this third booster will be the last, but that is yet to be determined, while we are still in the midst of a pandemic where so many are still becoming infected.

Regarding your question on how we can be proactive in the future, we just wrote up an article about the good news received about the Astra Zeneca monoclonal antibody study results that can be found here. We are hopeful that COVID-19 monoclonal antibody therapies will be the proactive answer for those with CLL in the very near future. In the meantime, we must continue to be extremely cautious, wearing a tightly fitted facemask at all times (preferably N-95s) and avoiding crowds around those who are unvaccinated as much as possible. We did create a COVID-19 plan for those with CLL to fill out that can help you be proactive should you ever have known exposure or become infected. You can find more information on that here, and print the handouts at the bottom of the page. 

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