As more Americans continue to get vaccinated against COVID-19, U.S. officials continue to monitor for severe allergic reactions and other adverse events after getting the vaccine.
A Florida doctor has died several weeks after receiving a COVID-19 vaccine, although it's not yet clear whether his death Monday was related to the shot he received on Dec. 18.
Dr. Gregory Michael, 56, an OB-GYN at Mount Sinai Medical Center in Miami Beach, died after suffering a hemorrhagic stroke apparently resulting from a lack of platelets.
Miami medical examiners are investigating his death, the Florida Department of Health said in a statement.
"The CDC and FDA are responsible for reviewing COVID-19 vaccine safety data and presenting that information for federal recommendations on vaccine administration," communications director Jason Mahon said in an email. "The state will continue to provide all available information to the CDC as they lead this investigation."
The Centers for Disease Control and Prevention said early safety monitoring has detected 21 cases of anaphylaxis, a severe allergic reaction, after receiving the Pfizer-BioNTech COVID-19 vaccine.
Anaphylaxis is a serious, life-threatening allergic reaction and requires immediate medical attention, according to the American Academy of Allergy Asthma & Immunology. Symptoms can include skin rash, nausea, vomiting, difficulty breathing and shock. The most common anaphylactic reactions are to foods, insect stings, medication and latex.
In a Facebook post, Michael's wife, Heidi Neckelmann, said he sought emergency care three days after the shot because he had dots on his skin that indicated internal bleeding.
The condition she said led to his stroke, called thrombocytopenia, results from a lower-than-normal number of platelets, which help the blood clot.
In extremely rare cases, the measles, mumps and rubella vaccine has been linked to thrombocytopenia in young children, according to a 2003 study. The condition can also be caused by cancer, anemia, heavy drinking, viruses, some genetic conditions, toxic chemicals and medications such as diuretics and the rarely used antibiotic chloramphenicol.
The cases were detected in a pool of 1,893,360 first doses administered from Dec. 14 to 23. This translates to 11.1 cases of anaphylaxis per 1 million doses, said Dr. Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases, in a media briefing Wednesday.
This is higher than the flu vaccine, which has an average outcome rate of 1.3 cases per 1 million doses. However, Messonnier said the rate of anaphylaxis in the COVID-19 vaccine is still considered a rare outcome.
“We all would hope that any vaccine would have zero adverse events, but even at 11 cases per million doses administered – it’s a very safe vaccine,” she said.
In 86% of the cases, symptoms began within 30 minutes of vaccination, and 81% of them occurred in people with a history of allergies or allergic reactions, including anaphylaxis events. Most of the patients who reported having this severe allergic reaction – 90% – were women.
Dr. Thomas Clark, an epidemiologist at the CDC, said 19 patients used epinephrine, a medication used to treat severe allergic reactions in an emergency situation, and all of the patients whose information was available recovered.
A total of 29 cases were reported as of Wednesday and included some patients who received the Moderna vaccine, Clark said. The agency is still investigating these cases and plans to include them in a future report.According to the CDC, about 17 million doses of COVID-19 vaccine have shipped throughout the country, shy of the 20 million federal officials promised to be distributed by the end of 2020. As of Wednesday, 4.8 million people have been vaccinated.
The CDC said it will continue to monitor for adverse events, including anaphylaxis, and will regularly assess the benefits and risks of vaccination. However, the COVID-19 vaccine continues to be “an important tool in efforts to control the pandemic.”
“We’re in the setting of 2,000 COVID deaths per day,” Messonnier said. “It’s still a good value proposition to get someone vaccinated. Their risk from COVID and poor outcomes from COVID is still more than the risk of a severe outcome from the vaccine.”