A Letter Of Warning To The Pennsbury School Board in Pennsylvania: Mandating Vaccination Of COVID-Recovered And Already Immune Persons Is Hazardous.

Pennsbury is poised to mandate COVID-19 vaccination for all eligible persons in accordance with CDC guidelines. But, extending such a mandate to persons with already established immunity from a prior COVID-19 infection, is medically unnecessary and only risks harm and liability to all involved.

Hooman Noorchashm
4 min readAug 13, 2021
The Pennsbury School Board in Pennsylvania is poised to impose a COVID-19 vaccine mandate on members of the school district — But extending such a mandate to COVID-recovered and already immune members of the Pennsbury community is an unnecessary and potentially dangerous proposition from a medical and ethical perspective.

Honorable members of the Pennsbury school board,

I write this open letter of warning to you as a Pennsylvania physician and immunologist — and as a taxpayer and resident of your district.

My qualifications to comment include MD and PhD degrees from the University of Pennsylvania with over a decade of specialized training in immunology — and a long track record of NIH supported research in immunological science. I’ve also served on the Medical school faculties at Penn, Harvard and Thomas Jefferson University. I currently hold unrestricted medical licenses in the states of PA and NJ.

Here, I write as a concerned physician-immunologist and because I know that in the coming week you may be planning to impose a COVID-19 vaccine mandate on all eligible persons within our school district.

While as a physician and immunologist, it is my professional opinion that all NON-IMMUNE adults ought to be encouraged to undergo COVID-19 vaccination to protect themselves and their communities, I have a very specific concern about a blanket vaccination policy applied indiscriminately.

I hope that you will very carefully read the substance of my concern, below, and have the clarity of vision and purpose to act upon it to maximally and rationally protect the Pennsbury community.

Currently, in the US and likely in the Pennsbury school district, nearly 30% of the population has already contracted and recovered from COVID-19. The vast majority of these “COVID-recovered” individuals are already very well immune to re-infection.

In fact, several large scale recent studies including one from the Cleveland Clinic and another from Harvard Medical School have demonstrated that the incidence of “re-infection” in COVID-recovered Americans is extremely low.

The Harvard Study, demonstrated that the incidence of re-infection in COVID-recovered persons is 0.2%. This is far lower than the incidence of vaccine failure cases and “breakthrough infections” in the case of “fully vaccinated” persons which is likely to be well over 10%.

Thus, as most immunologist understand, COVID-recovered persons, especially those with serological evidence of antibody immunity to COVID-19, are equally, if not better protected from subsequent infection than their “fully vaccinated” peers.

Therefore, it is critical for the Pennsbury School Board to understand that mandating vaccination of the already immune and COVID-recovered members of the community would be a terrible judgement error, because it violates the principle of “Medical Necessity”.

At the core of adhering to ethical concept of “Medical Necessity” is the goal of promoting safe medical practices and policies. Because whenever anything medically unnecessary is done to a person, that person is only absorbing the risk with little to no added benefit.

In addition to this important principle, as an immunologist, I am writing to inform you that indiscriminate vaccination of recently COVID-convalescent members of your community is a potential hazard to their safety.

You’ve likely heard about cases of hyper-inflammatory reactions, blood clots and myocarditis complications in a minority subset of COVID-19 vaccinated people. These risks associated with the COVID-19 vaccine, though infrequent, are real — but they can be minimized by avoiding vaccination of COVID-convalescent or recently infected persons. It is a very serious concern that vaccination of recently infected persons, in particular, could trigger these complications.

Therefore, I am writing to respectfully warn the board that members of the Pennsbury school district who are COVID-recovered or demonstrate evidence of antibody immunity to SARS-CoV-2 are placed at risk of harm from mandated vaccination. Thus, all such persons within Pennsbury School District, ought to be automatically exempted from any vaccine mandate.

It is critical for the board to appreciate that COVID-recovered and already immune members of the district pose little to no harm to themselves or others — and that they are equally, if not more protected from subsequent infection than their “fully vaccinated” peers. Whereas, mandating such individuals to undergo a unnecessary vaccination only poses a risk of harm to them and opens your district to both moral and potential legal liability.

My respectful recommendation is that the Pennsbury School Board exempt all COVID-recovered and already immune members of the community from any proposed vaccine mandate. Such persons are already robustly immune to SARS-CoV-2 and could only be harmed by an indiscriminate blanket approach to COVID-19 vaccination.

It is my sincere hope that reason and appropriate safety precautions can prevail within Pennsbury School District — and that you are able to resist incorrect “one-size-fits-all” group-think when it comes to imposing a vaccine mandate in the large number of COVID-recovered and already immune members of our community. In regard to this particular subset of people in our community, blindly following current CDC guidance on COVID-19 vaccination has a potential to irreparably harm members of our community.

Please do not hesitate to contact me with questions or comments.


Hooman Noorchashm MD, PhD.




Hooman Noorchashm

Hooman Noorchashm MD, PhD is a physician-scientist. He is an advocate for ethics, patient safety and women’s health. He and his 6 children live in Pennsylvania.