At the moment the United States and the rest of the world are participating in an unprecedented experiment of being vaccinated for COVID-19 to end the pandemic without completely knowing long-term risks. The Federal Drug Administration (FDA) has authorized the emergency use for the vaccine, based upon clinical trials that showing that the vaccine is highly effective in reducing or preventing COVID-19 disease and morbidity.¹ Because it is an experimental procedure, it is necessary to monitor and follow-up everyone who is vaccinated in order to identify possible rare complications that could occur in the future. What has been reported is a very rare complication of anaphylaxis that may occur immediately after administration of the vaccine by Pfizer-BioNTech (4.7 cases per million) and Moderna (2.4 cases per million)²; however, this data may under report the actual negative side effects.

In the recently published prospective study by Blumenthal et al. (2021), 64,000 employees associated with Mass General Brigham (MGB) were actively followed through a multipronged approach, including email, text message, phone, and smartphone application links.³ The complication rate of acute allergic reaction rate was 2.1% and the severe anaphylaxis reaction was 247 cases per million. This is 50 times higher than the previously reported results, which depended on voluntary reporting instead of active all-participants follow-up. Nevertheless, the benefits of vaccination far outweigh the risk of anaphylaxis, which was experienced within the first 15-30 minutes after the vaccination and treatable. What is disturbing is that at this moment, the USA does not have a systematic long-term follow up strategy for all the people who vaccinated to identify possible delayed long-term side effects since it depends upon voluntary reporting, however, rare. Thus, we are all part of an uncontrolled experiment in which I am also participating.