The doctor in Massachusetts believed to be the first in the U.S. to suffer an adverse reaction to Moderna’s coronavirus vaccine said that the symptoms began within moments of the shot being administered.Dr. Hossein Sadrzadeh, of Boston Medical Center, received the vaccine on Thursday, and at first believed he was experiencing anxiety related to the shot, he told NBC 10 Boston. When his tongue started tingling and then turned numb, he realized his was dealing with a reaction.”My blood pressure was really down, so this is the time that I knew that this was anaphylactic shock,” he told the news outlet. “My heart rate is up, I’m sweating so my blood pressure is really down. I’ve had this before so I had my EpiPen and I administered myself.”FIRST PFIZER CORONAVIRUS VACCINE RECIPIENT IN UK GETS SECOND DOSEThe geriatric oncology fellow, who has a history of severe shellfish allergy, recovered by Friday, he said. Sadrzadeh said he would like to see Moderna and Pfizer do more investigative work on the allergic reactions suffered by several vaccine recipients since the rollouts began, but that it is important that people continue to receive the shot.The Centers for Disease Control and Prevention (CDC) is investigating at least six reactions related to Pfizer and BioNTech’s coronavirus vaccine, and several other instances were reported in the U.K. Over 11 million doses of coronavirus vaccines have been distributed across the U.S. thus far, with just over 2.1 million shots administered.Experts have said that while allergic reactions, including severe ones, can occur after receiving a vaccine, it remains a rarity. The CDC has since issued guidance that advises anyone with a history of severe allergic reaction to any ingredient in the Pfizer and BioNTech vaccine to not get vaccinated. Those with history of severe allergic reaction to other vaccines or injectable therapies should consult their doctor before receiving a vaccine.CLICK HERE FOR COMPLETE CORONAVIRUS COVERAGEFor now, those who have suffered a severe reaction to the first shot are not advised to receive the second dose.The country had set a goal of getting at least 20 million doses administered by the end of 2020, but it appears that officials will fall short of that goal. Dr. Anthony Fauci, the nation’s leading infectious disease expert, told media that he expects the vaccine campaigns to pick up in January, potentially increasing the current pace of injections.