COVID-19 Vaccine Side Effects

By Dr. Magdy Badran

Currently, in various areas of the world, COVID-19 vaccines have been authorized for use. More than 1.29 billion doses have been administered across 174 countries. The latest rate was roughly 20.8 million doses a day.

Common side effects

Vaccines allow the body to build immunity by activating T and B lymphocytes, cells that, respectively, recognize the targeted virus and produce antibodies to combat it.

A vaccine cannot cause COVID-19. No vaccine contains a complete form of the virus responsible for this illness. While their body builds immunity, it is normal for a person to experience minor side effects.

According to the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO, common side effects of a COVID-19 vaccine include: a fever, fatigue, headaches, body aches, chills and nausea.

A person might also experience side effects around the injection site, which is usually the upper arm. These might include swelling, pain, redness, an itchy rash, and other mild forms of irritation. People sometimes refer to this issue as COVID arm.

Health authorities recognize that each of the 13 authorized COVID-19 vaccines can cause side effects. These are often mild and last for only a few days. They are not unexpected.

Allergic Reactions and Anaphylaxis

Rarely, a person experiences an allergic reaction to one or more of the ingredients in a vaccine. They might develop hives or another type of skin rash, swelling, and respiratory symptoms.

A severe allergic reaction is called anaphylaxis, and it involves low blood pressure, nausea, and difficulty breathing, among other symptoms. Anaphylaxis is an extremely rare side effect of vaccination. According to the CDC, around 2–5 people per million, or fewer than 0.001% of people vaccinated in the U.S. have experienced anaphylaxis afterward.

Allergic reactions to mRNA vaccines have been of particular concern, as they contain a chemical, called polyethylene glycol (PEG), that has never been used in an approved vaccine before. PEG is in many drugs that have occasionally triggered anaphylaxis. In these vaccines, it coats the mRNA molecule and supports penetration into cells.

There are similar concerns about the Janssen vaccine, which contains polysorbate 80, a chemical that is structurally related to PEG.

A study about allergic reactions to mRNA COVID-19 vaccines noted that most people who experienced anaphylaxis afterward had a history of allergies and this particular severe reaction.The data suggest that there is a very low risk of anaphylaxis as a result of mRNA COVID-19 vaccines. Regardless, the CDC recommend that vaccine administrators conduct prescreening for specific allergic reactions. These vaccines are safe for people with common allergies, such as to foods, pets, environmental elements, latex, and oral medications.

The CDC also recommend that anyone who has had an allergic reaction to one dose of a vaccine not receive a second dose of the same type of vaccine.

Frequency of Side Effects in Women

Side effects appear to be more commonly reported in women than men. A study by CDC researchers shows that 78.7% of adverse event reports submitted during the first month of U.S. vaccination involved women. Another study observed that females represented 15 out of 16 people with anaphylaxis after a vaccine.

These findings are in line with a 2013 study on the H1N1 vaccine during the 2009 flu pandemic, which found higher rates of hypersensitivity reactions among females of childbearing age than other groups in the study population.

Reproductive hormones, such as estrogen and testosterone, may play a role in this sex discrepancy. A study in mice suggests that estrogen causes the body to generate more antibodies, leading to a higher immune response.

Potential Side Effects per Vaccine

Recently, there have been new concerns about serious side effects of COVID-19 vaccines. These effects may be coincidental, and there is currently not enough conclusive evidence to link these effects to specific vaccines. However, regulatory agencies are taking precautionary measures to investigate these safety concerns.

Pfizer-BioNTech and Moderna

The Pfizer-BioNTech and Moderna vaccines are both two-dose mRNA vaccines. People have reported similar, common side effects after the second doses of each.

These COVID-19 vaccines are the first vaccines approved for use in humans that incorporate mRNA technology. As a result, there are concerns about the long-term effects and a risk of altering the body’s genetic information.

People may be unaware that researchers have spent many years studying the potential of mRNA vaccine technology. There have been efforts to develop mRNA vaccines in the past, including Moderna’s human-based trial of an mRNA Zika virus vaccine. Furthermore, it is unlikely that an mRNA vaccine can alter genetic information. The mRNA in a vaccine does not enter the nucleus of a cell, where DNA is stored, and it degrades rather quickly in the body after it serves its purpose.

While fertility was not specifically studied in the clinical trials of the vaccine, no loss of fertility has been reported among trial participants or among the millions who have received the vaccines since their authorization, and no signs of infertility appeared in animal studies. Loss of fertility is scientifically unlikely.

Janssen (Johnson & Johnson)

The Janssen vaccine can also cause common vaccine side effects. The vaccine’s product information document provides details about precautions to take and the expected effects.

Oxford-AstraZeneca and Serum Institute of India

The European Medicines Agency (EMA) and Danish Health Authority recently observed that the Oxford-AstraZeneca vaccine has been followed by incidents of blood clots.

Of the 5 million people who received this vaccine, there have been 30 reported cases of blood clots. One case in Denmark was followed by death. On March 18, 2021, the EMA concluded that the Oxford-AstraZeneca vaccine is safe and does not increase the overall risk of blood clots. They pointed out that the incidence rate of blood clots in people who have had the vaccine is lower than that in the general population.

The EMA did acknowledge extremely rare cases of thrombocytopenia, an issue that supports blood clot formation, following the vaccination. They are now incorporating this into their vaccine product information. Still, they highlight a lack of causal evidence and emphasize that the benefits of vaccination still outweigh the risks.

Multiple countries, including Denmark, Norway, Germany, and France, had paused the distribution of this vaccine as a precautionary response to the initial reports of blood clots. Many of these countries plan to resume the use of this vaccine, and there are concerns that this event has slowed down the timeline of vaccine distribution throughout Europe.

The Serum Institute of India’s Covishield is the locally manufactured version of the Oxford-AstraZeneca vaccine. India has not reported any incidents of blood clotting related to Covishield and currently has no plans to discontinue its distribution. Drug regulatory agencies in India are still closely examining the data, however, to ensure that there are no causal links.

Sinopharm's COVID-19 Vaccines

The World Health Organization (WHO) has granted emergency approval for a COVID vaccine made by Chinese state-owned company Sinopharm. It is the first vaccine developed by a non-Western country to get WHO backing.The vaccine has already been given to millions of people in China and elsewhere.

The incidence of adverse effects from Sinopharm's two inactivated COVID-19 vaccines is 1.06 percent, based on emergency use of the two vaccines in China on more than 500,000 people as of December 1, which is far lower than the phase II clinical trial results. China's Sinopharm COVID-19 vaccine is safe and effective with no serious side effects.

Should I Receive a COVID-19 Vaccine?

Any form of medical treatment carries risks, but in many cases, these are outweighed by the benefits. The CDC recommend that people get vaccinated to curb the spread of the virus that causes COVID-19, except in very specific circumstances.

Receiving a vaccine does not guarantee full protection against COVID-19. People must continue to follow social distancing guidelines, wear a mask in public, and wash their hands frequently, among other precautions.

Meanwhile, more than 50 other COVID-19 vaccines are currently in phase 1–3 clinical trials. With new progress being reported every day, much of the world is beginning to look toward a future beyond the COVID-19 pandemic.