COVID-19 VACCINES: All your questions, answered!

Now that the Food and Drug Administration (FDA) has issued emergency authorisation for two coronavirus vaccines, Pfizer-BioNTech and Moderna, you may have a lot of questions about what this means for you and your loved ones.

Here are answers to some frequent questions.

What are the known side effects of the coronavirus vaccine?

The safety of each coronavirus vaccine is tested in pre-clinical and clinical trials. The most common side effects of coronavirus vaccines that have been approved are:

• pain at the injection site

• tiredness or fatigue

• headache

• muscle pain

• chills

• joint pain

• fever

• swelling or redness at the injection site

• nausea

• feeling unwell

• swollen lymph nodes (lymphadenopathy)

These side effects last for an average of one to two days. Most people have mild or moderate symptoms, while for some people symptoms may be more severe.

A few people who have been given the Pfizer-BioNTech vaccine outside of the clinical trials have had severe allergic reactions following vaccination.

People with a known history of a severe allergic reaction to any component of a coronavirus vaccine should not receive the vaccine, recommends the FDA.

In addition, the agency says people who have a severe allergic reaction to the first dose of a two-dose vaccine should not receive the second dose.

Once I’ve gotten my shot, am I immediately protected?

Nope: Covid vaccination is a process, and the full timeline for two-dose vaccines from manufacturers like Pfizer and Moderna is about a month and a half. After the first dose of the vaccine, the second dose comes three weeks later for Pfizer, and four weeks later for Moderna. Then, it takes around two weeks for the vaccine to kick in. There may be incomplete immunity – little or maybe no significant protection – after just the first dose or even within the first week after the second dose.

So once a person is fully vaccinated and it’s now two weeks after their final dose, are they completely protected from contracting and/or transmitting the coronavirus? Not quite. At that point, a person would be protected against illness that could result from the novel coronavirus – including cases serious enough to lead to hospitalisation or death. However, if they’re exposed to and infected with SARS-CoV-2, they may not get sick, but still shed the virus, potentially transmitting the infection to others. For this reason, it’s important for everyone – even those who have been fully vaccinated – to continue to wear face masks and practice physical distancing, at least until there is high-level uptake in their community.

And does that mean it would be safe(r) to fly on an airplane? In theory, yes: A fully vaccinated person can start to travel again with some confidence that they are now at a lower risk of getting sick with covid. But the decreased risk doesn’t mean there is no risk at all. The vaccines’ efficacy were not demonstrated to be 100 per cent. So, this is another reason for us to try and achieve the high-level population-wide immunity through vaccination.

Will we still have to wear face masks and socially distance after people start getting vaccines?

Yes – at least initially. It’s not going to be a light switch where one day the pandemic is suddenly over and everything is back to normal. Part of that is because while the high efficacy of the Pfizer and Moderna vaccines is promising, there are still plenty of unanswered questions. These include how long the immunity lasts, how much asymptomatic transmission by vaccinated people will occur, and how many people are willing to receive the vaccine.

Over time, as the vaccine becomes more readily available, we learn more about the durability of immunity and real-world effectiveness provided by the vaccine, and, hopefully, uptake reaches a critical threshold where we can achieve herd immunity, we should be able to scale back on the other preventive measures, but it’s not clear exactly when that will be. Some experts are predicting that will happen by the third or fourth quarter of 2021, but that could change depending on some of the unknowns.

When will children be able to get a covid vaccine?

That depends on when data from clinical trials involving children becomes available. Right now, Pfizer is testing the vaccine on children as young as 12, but is the only major pharmaceutical manufacturer to do so at this stage. We are likely months away from the vaccination of school-age children.

Before we put [the covid-19 vaccine] into the children, we’re going to want to make sure we have a degree of efficacy and safety that is established in an adult population.

When a vaccine is shown to be safe and effective in adults, it usually is in children as well – but not universally. Children’s immune systems are very different than adults’, as evidenced by their vastly different reaction to being challenged with a novel virus. A vaccine that is effective in adults may or may not work as well in children.