• More women reported they experienced side effects from the Covid-19 vaccine, a CDC study showed.
  • The survey conducted by the CDC analysed more than 13 million vaccine recipients as of January 13.
  • Women made up nearly 80% of the 7,000 recipients who reported side effects.
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Women made up a majority of those reporting adverse effects from the Covid-19 vaccine, a study by the Centers for Disease Control and Prevention showed.

Nearly 7,000 people reported to the CDC that they were experiencing side effects after receiving the vaccine, including symptoms of headaches, fatigue, and dizziness. Women made up nearly 80% of those who reported side effects.

The survey conducted last month by researchers at the CDC analysed safety data on the more than 13 million recipients of the coronavirus vaccine as of January 13.

Over the course of a month, a total of 13,794,904 Covid-19 vaccines were administered to Americans - of which 8,436,863 (61.2%) were administered to women.

Shelly Kendeffy, a medical technician in State College in Pennsylvania who received the Moderna Covid-19 vaccine, told The New York Times that immediately after receiving the shot, she felt fine.

However, by the afternoon: "My teeth were chattering, but I was sweating - like soaked, but frozen," Kendeffy told The Times. She said six of her seven female colleagues also experienced symptoms like body aches, chills, and fatigue, and the seventh woman who didn't display flu-like symptoms said she spent the night after the vaccine vomiting.

Of the eight male colleagues who were also vaccinated, Kendeffy said one had soreness, another got a headache, two felt fatigued, and four felt nothing at all.

Sabra Klein, a microbiologist and immunologist at the Johns Hopkins Bloomberg School of Public Health, told The Times she was "not at all surprised," given that "this sex difference is completely consistent with past reports of other vaccines."

In 2013, a study conducted by scientists revealed that adult women were at higher risk of reactions than men for the 2009 pandemic flu vaccine, and another study researching anaphylactic reactions to influenza vaccines between 1990 and 2016 showed that women accounted for a majority of the adverse responses.

Although women are at a higher risk of adverse effects, Klein said women shouldn't worry about the likelihood of side effects because "you are mounting a very robust immune response, and you will likely be protected as a result," she told The Times.

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