Public health officials are investigating the causes of several severe allergic reactions reported last week among hundreds of thousands of people vaccinated with the Pfizer-BioNTech coronavirus vaccine.
As of Friday (December 18th), six people who received jabs in the United States developed anaphylaxis, or a severe allergic reaction that could be life-threatening if left untreated. According to the Centers for Disease Control and Prevention (CDC). One of those patients developed anaphylaxis after being previously vaccinated against rabies, but it is not clear whether the other participants had a previous history of severe allergies.
Last week, the two men in the UK both had a history of severe allergies and developed anaphylaxis-like symptoms after receiving the Pfizer vaccine. Or foods to avoid vaccines, Live Science previously reported.. In the United States, the Food and Drug Administration (FDA) says that only people who have previously had a severe allergic reaction to any of the ingredients listed in other vaccines or Pfizer vaccines should avoid injections. Recommended.
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But are these events really allergic reactions to the vaccine? If so, what is causing them? One possibility is the chemicals commonly used in laxatives in both Pfizer and Moderna vaccines. However, some cases may not be true allergic reactions, one expert told Live Science. And in either case, the reaction is very rare.
Pfizer-BioNTech Vaccine Ingredients:
—MRNA
— Lipid (4-Hydroxybutyl) Azaneziyl) Bis (Hexane-6,1-Diyl) Bis (2-Hexyldecanoate) & 2[(polyethylene glycol)-2000]-N, N-ditetradecycloacetamide & 1,2-distearoyl-sn-glycero-3-phosphocholine & cholesterol
— Potassium chloride
— Basic potassium phosphate
–Sodium chloride
— Dibasic disodium hydrogen phosphate dihydrate
— Sucrose
There is no way to know for sure, but one component of the Pfizer vaccine is suspected. A compound called polyethylene glycol (PEG) “may be the cause,” Dr. Peter Marks, director of the Food and Drug Administration’s (FDA) Center for Biologics Evaluation and Research, told reporters on Friday (December 19). Told to. The compound is also included in the Moderna vaccine, which has a similar composition to Pfizer, and received urgent approval in the United States on December 18.
This is the main cause, as the remaining components of Pfizer’s vaccine are “lowly likely lipids, salts, sugar, and allergens.” Dr., an allergist and immunologist at NYU Langone Health who was not involved in the development of the vaccine. PEG is found in many medicines, including those that treat constipation, but allergies to it are rare, Parik said.
Rare, but not unheard of: Some drugs, including PEG, can cause anaphylaxis. According to Science Magazine.. Also, previous exposure to the compound may have put some people at risk for anaphylaxis by developing high levels of antibodies against it.
Moderna vaccine ingredients:
—MRNA
— Lipid (SM-102, polyethylene glycol [PEG] 2000 dimyristoylation glycerol [DMG],)&cholesterol
& 1,2-Distearoyl-sn-glycero-3-phosphocholine [DSPC])
— Trometamine
— Trometamine hydrochloride
— Acetic acid
–Sodium acetate
— Sucrose
While concerned, “The important thing to note is that it’s not certain that all of these were really allergic reactions,” Parik told Live Science. She said that some other conditions can mimic allergic reactions and they are much more benign. One such condition is “vasovagal syncope”. This happens when people become very anxious (for example, due to needles) and their heart rate and blood pressure drop and they faint.
“True allergic reactions to vaccines are very rare,” she said. “Statistically, you are more likely to be struck by lightning than a true anaphylactic response to the vaccine.” The average chance of developing anaphylaxis after vaccination is about 1.31 in 1 million. .. 2015 study published in Journal of Allergy Clinical Immunology..
Still, “it’s very important to have a complete history, evaluate these incidents, and get a better understanding of what’s going on,” Parik said.
Even if all of these prove to be true allergic reactions, they occur in only a small percentage of hundreds of thousands of people in the United States who are already receiving the Pfizer vaccine. These incidents “may be making news, but many people are accepting the vaccine without problems,” Parik said. As of December 19, Pfizer’s coronavirus vaccine had been given to healthcare professionals across the United States approximately 272,000 times. And as of December 20, that number had increased to 556,300 times. According to the CDC.. (Still, if all these cases are supported, it means that the Pfizer vaccine is more likely to cause an allergic reaction than other vaccines.)
Neither Moderna nor Pfizer clinical trials found that the vaccine caused serious adverse events such as anaphylaxis. Those who were allergic to any of the components of the vaccine were excluded from the study, but those with severe food or drug allergies were not excluded. According to Science Magazine, Pfizer’s trial excluded people who had a serious response to the vaccine in the past.
The National Institutes of Health (NIH) has begun research to investigate the causes of these allergic reactions to Pfizer’s coronavirus vaccine and will recruit volunteers with a history of severe allergic reactions. According to the Washington Post..
But in the meantime Recommended by CDC Everyone who receives the Pfizer vaccine should be observed for 15 minutes after the jab (this is a common practice for all vaccines). According to the conversation). If you have a history of severe allergic reaction, please stay at the clinic or clinic for about 30 minutes. According to the CDC, all six patients with severe reactions had them within this “recommended observation period” and were treated promptly.
Originally published in Live Science.