We know you might be anxious about that, but really, there's nothing to be worried about.

Side effects are common

Health Director-General Tan Sri Dr Noor Hisham Abdullah said that getting sick after receiving a COVID-19 booster shot is normal.

Dr Noor Hisham shared a video titled 'Vaccine side effects are actually a good thing' on his Facebook page on Friday (14 January).

According to Dr Noor Hisham, every vaccine, not just COVID-19 ones, will bring some sort of side effects such as muscle pain, fever or headaches; and some of the newer COVID-19 vaccines are even likelier to give you those side effects.

However, there's nothing to worry about.

“But the scientists who work most closely with vaccines emphasise that when a vaccination makes you feel sick, it's almost never a bad sign. And once you understand why vaccine side effects happen, you may even be happy to get that headache,” he wrote.

This came after statistics posted on the Health Ministry's CovidNow portal showed that many Malaysians are still worried about post-COVID-19 vaccination symptoms.

To date, only 37.6 per cent of the adult population in Malaysia have received their booster shots.

Why side effects are a good thing

If you're still a little bit concerned, here's why getting side effects is a good thing: it means that the vaccine is working.

According to this article by the World Health Organisation (WHO), vaccines are designed to give you immunity against a virus without you actually having to get it.

When a vaccine is injected into your blood stream, your immune system is telling your body to react in certain ways to fight it; for example, raising your body temperature in order to kill the virus or increasing blood flow so more immune cells can circulate.

Low-grade symptoms such as fever or muscle pain are signs that your body is responding to the vaccine, specifically the antigen -- which is a substance that triggers an immune response -- and is gearing up to fight the virus.

Even if you don't get any side effects, don't worry; that's normal too, because everybody responds differently.