By ITV News Multimedia Producer Ann Yip
But they are nothing to worry about and indicate a strong immune response to the vaccines, the Medicines and Healthcare products Regulatory Agency (MHRA) has said.
In clinical trials of the Oxford/AstraZeneca vaccine, "adverse reactions" were generally milder and reported less frequently in people aged 65 and older, the medicines regulator noted in a report.
The findings were similar with the Pfizer/BioNTech vaccine, with fewer adults older than 55 reporting side effects.
The most common reactions reported in the vaccine rollout so far are soreness in the injection area, headache, fatigue, muscle pains, chills, fever, 'flu-like' symptoms, nausea, dizziness, weakness and rapid heartbeat.
These reactions were usually resolved within a day or two, according to MHRA.
A spokesperson for the regulatory body explained: "In clinical trials, adverse reactions were generally milder and reported less frequently in older adults, which probably reflects the fact that younger adults tend to mount a stronger immune response to vaccines in general.
"This is also reflected in the Yellow Card reports (feedback from people who have taken the vaccine). This is not unusual and the types of side effects is generally the same across the age range, even if reported more frequently in younger adults."
Not everyone has reported side effects from the vaccine.
Millions of people - more than 18 million - have been given the first dose of a Covid vaccine, and as of February 14, more than 58,000 Yellow Card reports of suspected side effects have been received by the MHRA.
For the Pfizer/BioNTech vaccine, 26,823 Yellow Card reports have been received, for the Oxford/AstraZeneca vaccine, there were 31,427, and 177 reports did not specify the brand of the vaccine.
Tazz Stander, 45, who describes herself as “incredibly fit and healthy”, said she had the chills and a fever after getting the vaccine and her symptoms lasted for just a day.
Tazz Stander describes what the side effects were like after taking the vaccine:
She admitted she was seeing a trend with her peers where younger people were getting side effects, while her friends aged 70 and over reported no side effects.
Tazz, who takes immune suppressing drugs for rheumatoid arthritis, said she started shivering two hours after she got her first dose of the Oxford/AstraZeneca jab on January 26.
The media agency worker from Bushey initially thought she was just cold as it was snowing. She told ITV News at one point her teeth were chattering. Her fever kicked in half an hour later.
But her ordeal was short-lived. She said: “I slept through the night and woke up the next morning and I was fine.”
Although her fever and chills subsided, her arm, where she received her injection, remained sore for five days.
But she reassured others saying: "I wouldn't say it hindered my ability to work, but I wasn't as sharp as I should've been. I didn't feel the need to say to my boss, 'I need to take time off because I don't feel great'."
She continued: "It's not as scary as people think. The side effects are so, so manageable."
Melinda Elgie says she felt like she had Covid all over again:
Melinda Elgie, a 47-year-old dementia nurse, said she felt like she had coronavirus all over again after taking her AstraZeneca jab on January 17. The only difference was that instead of feeling poorly for six weeks, she only had symptoms for four days.
The nurse from Haywards Heath, who had Covid-19 for about six weeks from the beginning of December, said: "I was really, really sick with all symptoms of Covid for about three days afterwards.
"All my bones in my body were really sore, it felt like I’d been run over by a truck. I didn’t have a cough, it was just fatigue. I was just sleeping for 14-15 hours a day, and it was just severe muscle pain."
But she said: "It was nothing like having Covid."
As a dementia nurse, Melinda said she observed many of her older patients had milder side effects: "All my patients are 80 years and above, some in their 70s. They all had their vaccinations, and they had a sore arm. But people with vaccinations my age or younger, they definitely have a worse reaction. And it just blows my mind."
Melinda's 22-year-old son Duncan, a care home worker, also reported feeling rough a few hours after getting the AstraZeneca jab on the afternoon of January 4.
Duncan Elgie said he felt like he had been run over by a car after taking the vaccine:
He said: "I was fine up until about 6pm or 7pm and I started to feel really drained and it felt like I had been run over by a car. My bones were really sore and it was really difficult to move. I had a slight headache, it wasn’t too bad. And that lasted all the way through the night until the next day at 11am."
But the care home worker said from speaking to his peers aged 18 to late 50s, younger and older people had the same sort of side effects. In fact, he found more middle-aged people within his circle had side effects than his younger peers.
He admitted he did not know much about how residents at his care home reacted to the vaccine, but he said no one had any life threatening side effects.
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