Last week, a health professional at Bartlett Regional Hospital in Juneau, Alaska, sat down to receive the first dose of the Pfizer / BioNTech vaccine. According to the protocol, the middle-aged woman needed to be monitored for 15 minutes after receiving the injection. At the ten-minute mark, according to the New York Times, she began to experience symptoms of an anaphylactic reaction, which can be potentially fatal.
The healthcare professional reportedly started to experience shortness of breath when a rash spread over her face and torso. Naturally, a high heart rate followed. At first, she received an injection of epinephrine and her symptoms subsided – but not for long. The symptoms returned and she was transferred to the intensive care unit, where she stayed for at least two nights. According to a recent presentation by the United States Centers for Disease Control and Prevention (CDC) on December 19, this unidentified health professional is one of six cases of anaphylaxis among the 272,001 people who received the COVID-19 vaccine. in the United States.
Medical experts emphasize that severe allergic reactions to vaccines are rare, but they can happen.
“This is something we see with vaccines,” said Amesh Adalja, a senior researcher at the Johns Hopkins Center for Health Safety, in an interview with Salon. “The main thing is that when you get the vaccine, you are in a place where people will be watching you to make sure it doesn’t happen.”
Adalja added: “If you have a prescription for epi-pen or if you have had an allergy to injectables in the past, which means that you received an injection or something and had an allergic reaction, you should talk to your doctor about vaccination and be much more cautious about how quickly you get up from the vaccination site. “
The Pfizer vaccine is a relatively new type of vaccine that depends on synthetic messenger RNA. When a person receives the first injection of the vaccine, a customized version of synthetic messenger RNA (mRNA) is injected into the body, which causes cells to produce proteins that resemble the spine-shaped proteins that coat the SARS-CoV virus. -two. The immune system learns to recognize the peak, which means it will know how to attack a real version of the coronavirus if it enters the body. The second dose of the vaccine given three weeks later is similar to a booster.
According to a report in the journal Science, it may not be the vaccine itself that is causing these rare, albeit serious, allergic reactions, but a common chemical compound called polyethylene glycol that is linked to the lipid nanoparticles in which mRNA hitches – essentially packaging used to transport mRNA to the human body. Polyethylene glycol has never been used before in an approved vaccine, but it is found in many medications and in some everyday products. The Science report says that some experts are beginning to suspect that previous exposure to polyethylene glycol may put patients at risk for an anaphylactic reaction to the vaccine because they have already developed antibodies against it. They cite a 2015 study that suggests that 7% of people have enough anti-polyethylene glycol antibodies that can predispose to anaphylactic reactions.
But not everyone agrees with that connection.
“If it is polyethylene glycol, we should see a similar reaction with the Modern vaccine,” said Adalja, noting that it also contains PEG.
Sharon Castillo, a spokesman for Pfizer, told Salon in an email that the company is examining “every detail” of Alaskan reports (a second health professional also had an allergic reaction).
“We will closely monitor all reports suggestive of serious allergic reactions after vaccination and update the labeling language if necessary,” said Castillo. “The prescribing information contains a clear warning / precaution that appropriate medical treatment and supervision should always be available in the event of a rare anaphylactic event following administration of the vaccine.”
Castillo added that participants in the Phase 3 study were excluded if they had a history of serious adverse reactions associated with a vaccine. Pregnant women and children under 16 were also excluded.
“Overall, there were no safety signs of concern identified in our clinical trials, including any signs of serious allergic reactions associated with the vaccine,” said Castillo. “However, reports of adverse events outside of clinical studies are a very important component of our pharmacovigilance activities.”
The National Institute of Allergy and Infectious Diseases (NIAID) is conducting a study in collaboration with the Food and Drug Administration (FDA) to further examine allergic reactions and a possible link to PEG.
Adalja emphasized the importance of not worrying about these reports.
“It does not diminish my confidence in this vaccine; whenever you have an injection, a small percentage of the population has an allergic reaction, and this is something we are preparing for, ”said Adalja.