Mixing Covid Vaccines May Not Be a Great Idea, Research Shows

Data suggests mixing vaccine brands increases the risk of mild to moderate side effects

Thinking about mixing up your covid vaccine brands? Preliminary data from Oxford’s Com-Cov study on mixing and matching first and second vaccine doses shows it increases the frequency of mild to moderate side effects. The results have just been published in a research letter in The Lancet.

The Oxford Vaccine Group’s Com-Cov vaccine trial is studying the use of different combinations of approved COVID-19 vaccines for the first and second immunization doses. The study is being led by the Oxford Vaccine Group (Chief Investigator Associate Professor Matthew Snape) and delivered by a network of trial sites across the UK. The study is funded by the Vaccine Task Force and the National Institute for Health Research (NIHR). According to Prof. Snape;

“Whilst this is a secondary part of what we are trying to explore through these studies, it is important that we inform people about these data, especially as these mixed-doses schedules are being considered in several countries. The results from this study suggest that mixed dose schedules could result in an increase in work absences the day after immunization, and this is important to consider when planning immunization of healthcare workers.”

He added the following, to ensure people are aware of the absence of any danger.

“Importantly, there are no safety concerns or signals, and this does not tell us if the immune response will be affected. We hope to report these data in the coming months. In the meantime, we have adapted the ongoing study to assess whether early and regular use of paracetamol reduces the frequency of these reactions.”

Participants who had Pfizer/BioNTech followed by Oxford/AstraZeneca, and Oxford/AstraZeneca followed by Pfizer/BioNTech, 4 weeks apart, saw more reactions than those who had two doses of the same vaccine. It’s important to note that these data were obtained in participants aged 50 years and older, and reactogenicity (the patient’s reactions to the vaccine) might be higher in younger age groups for whom a mixed vaccination schedule is being advocated in countries like Germany, France, Sweden, Norway, and Denmark.

So if you run the risk of feeling bad for a day or two, perhaps even missing a day’s work, should you still get the vaccine? Absolutely, here the risk explained in a simple graphic, courtesy of Com CoV.

How Covid affects the population /ComCov

Common symptoms of COVID-19 include fever, tiredness, dry cough, and changes to taste and smell. Whilst about 80% of infected people have no or mild symptoms and will recover from the infection without needing special treatment, approximately 10–15% of cases (2–3 in 20) progress to develop severe symptoms, and about 5% (1 in 20) become critically ill.

The Covid vaccines reduce the odds of developing severe Covid dramatically. If we take a group of 100 critically ill Covid patients that haven’t been vaccinated, reverse the clock, and vaccinate them before they become ill, only between 5 and 10 of these individuals would actually become severely ill. That’s 90–95 people’s lives saved and as Covid mutates and becomes more infectious to a younger demographic, that could be your life on the line. Get the vaccine if you haven’t had it yet.

So what are these mild to moderate side effects?

Again, Com Cov comes to the rescue with an extensive list they’ve compiled and we’ve duplicated it below for your convenience.

Common side effects

People very often have tenderness, pain, warmth, redness, itching, swelling or bruising or less commonly have a small lump in their arm where they have been vaccinated.

Other common systemic side effects

Some people can develop these symptoms after vaccination. They usually last for less than a week after you are vaccinated (more commonly 24–48hours afterward).

  • Fatigue
  • Headaches
  • Flu-like symptoms, such as high temperature, sore throat, runny nose, cough and chills
  • Muscle aches
  • Joint aches
  • Feeling unwell (malaise)
  • Feeling sick or nauseated or vomiting

Other less common side effects:

  • Abdominal pain
  • Decreased appetite
  • Feeling dizzy
  • Swollen lymph nodes (glands)
  • Excessive sweating, itching skin or rash

These symptoms can be reduced by the use of paracetamol around the time of immunization and over the next 24 hours.

After vaccination with the BNT162b2 (Pfizer/BioNTech) vaccine, difficulty sleeping has been observed in fewer than 1 in 100 people, and weakness of the muscles on one side of the face has been observed in fewer than 1 in 1000 people. These are transient symptoms, in other words, they pass quickly.

Updated on June 14, 2024 12:07 pm
Updated on June 14, 2024 12:07 pm
Updated on June 14, 2024 12:07 pm
The article lives hereMixing Covid Vaccines May Not Be a Great Idea, Research Shows
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