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Worried about anaphylactic reactions and side effects? Experts answer FAQs on COVID-19 vaccination

Experts also discuss why choosing your vaccine is complicated and why you should get vaccinated on CNA’s Heart of the Matter podcast.

Worried about anaphylactic reactions and side effects? Experts answer FAQs on COVID-19 vaccination

A healthcare worker receives the coronavirus disease (COVID-19) vaccine at the National Centre for Infectious Diseases (NCID) in Singapore December 30, 2020. Lee Jia Wen/Ministry of Communications and Information/Handout via REUTERS

SINGAPORE: Singapore received its first shipment of COVID-19 vaccines, developed by Pfizer-BioNTech on Dec 21.

The Government accepted the Expert Committee on COVID-19 Vaccination’s recommendations on the overall vaccination strategy on Dec 27.

Forty healthcare workers received their first dose on Dec 30, with plans for the elderly to be vaccinated from February onwards.

The Singapore Government has also encouraged all medically eligible residents to come forward to get vaccinated, as authorities ready clinics and vaccination centres.

We posed questions regarding the COVID-19 vaccine from our Facebook followers to Associate Professor Lim Poh Lian, member of the Expert Committee for COVID-19 Vaccination and Prof Teo Yik Ying, Dean of Saw Swee Hock School of Public Health on the Heart of the Matter podcast.

READ: No corners cut in Singapore’s COVID-19 vaccine rollout, says expert panel doctor

Q: Why can’t I choose the vaccine I want?

Prof Teo: I see it as a very simple demand and supply problem. Right now, the world is actually in vast shortages of vaccine supply ... But in order for people to have a choice, you are going to say that I need to have perhaps 5 million doses of the Moderna, 5 million doses of Pfizer and 5 million doses of Sinovac, just in case people want to choose one or the other.

That is impossible. I would say that is also very irresponsible for countries to try and hoard vaccine supply in this manner in order to offer a choice to its people.

Q: How concerned should we be about reported anaphylactic reactions to the vaccine?

Prof Teo: It is important to highlight that, right now, when people read the newspaper, they read reports of adverse reactions.

That’s when people start to get the impression that “oh, actually, these vaccines are not that safe. But if you read not just the headline, but the details ... they say this doctor who experienced an adverse side effect has a history of allergies.

One important fact is, what we do know right now about the vaccines are what kind of people are medically suited to take the vaccines and who are the ones that are medically unsuited.

Assoc Prof Lim: People can get allergic reactions to penicillin. (If) they haven't got a history, the first time they take it or the second time they take it, they could get a really bad reaction.

It doesn't mean that we never use penicillin ever again. We have to know when to look for the side effects and also, if someone has had the side effect, then they can't (be given the same vaccine) again.

Media attention is always on the dramatic, bad side effects of the vaccine.

It’s the one case of anaphylaxis that gets on the headlines. The 15,000 people that got vaccinated without anaphylaxis don’t get featured.

READ: COVID-19: Government accepts committee's recommendations on vaccine strategy, to begin vaccinating healthcare workers from Dec 30

Q: What if I get a bad reaction after taking the vaccine?

Assoc Prof Lim: If you look at the United States, for example, they allow people with a history of anaphylaxis to get the COVID vaccine. And they were observing them for 30 minutes.

People without a history of anaphylaxis can be observed for 15 minutes.

We are already putting an extra margin of safety and caution here in Singapore by requiring 30 minutes of everyone. We had wanted to make sure that this was done safely, and that people be reassured.

Severe allergies are defined as anaphylaxis, where people actually see their blood pressures drop. Or if they have swelling around their face, lips, eyes, throat, we would advise them to hold off for now, until we get more data and let other people get vaccinated first. If we know that it's safe after there's more data, then we might allow them to get vaccinated.

Q: What can I expect in the first 24 hours after getting the vaccine?

Prof Teo: We know what the normal side effects are – fever, swelling, some soreness, even some degree of fatigue. Those are the common side effects known to the Moderna and Pfizer-BioNTech vaccine.

Assoc Prof Lim: Those kinds of side effects tell you that your body's mounting a response to the vaccine. It's building an immune response to be ready for the real thing if you ever get exposed to it.

We have a vaccination card, and a vaccine information sheet that we give to everyone who gets the vaccine, about how to deal with it.

So if you're tired, rest. If you have a sore arm, don't play a game of golf. And if you get a fever, probably for the first day or so you can take Panadol but if it lasts more than a day or two, then we do ask you to see your doctor.

READ: NCID nurse becomes first person in Singapore to receive COVID-19 vaccine

Q: In Singapore, the community cases are low and everyone is going about their lives. So taking a vaccine doesn’t seem that important. Can I just wait?

Prof Teo: The vaccine takes time to be effective. From the point of taking the first dose, three weeks later, you take a second dose, and then maybe one or two weeks later before it's fully effective.

So from the time of receiving the vaccine, to the point that it truly protects you against an infection you're looking at a month or five weeks or more.

So that means that we cannot wait until the situation in Singapore is bad before we start to vaccinate people. A vaccine by nature is a preventive measure.

It is meant to protect people during peacetime such that when you're in a wartime scenario, when you're exposed to people potentially carrying the virus, you are protected from it.

Listen to the full podcast episode to hear the behind-the-scenes considerations and discussions going into what might be Singapore’s biggest vaccination programme ever:

Source: CNA/cr


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