Why do I need another Flu and COVID-19 vaccination?
Have you ever wondered why your childhood measles vaccination is still going strong, yet other illnesses need regular boosters to work best? There are a few reasons, but first a recap:
How do vaccines work?
Vaccines train the body to recognise an attack and mount an immune response through antibodies and other defence mechanisms. This response needs to be strong enough to decrease the severity of infection or bypass it completely.
Why do some vaccines last longer than others?
As with everything in science, there are several factors. Here are three to remember:
1. Viruses mutate at different speeds.
Flu, and now COVID-19, mutate quickly. Polio, for example, does not – making it far easier to contain and potentially eradicate.† When several mutations or variants develop, it's like dealing with a moving target. So, vaccines must adapt and change too.
Ryan Norris
Pharmacist TerryWhite Chemmart
Esperance, WA
2. Antibodies decay at different speeds.
The antibodies developed from measles and mumps vaccination take more than 200 years to diminish by half.† On the other hand, those for COVID-19 seem to last just several months.^ The thing is: the longer-lasting the antibodies, the longer-lasting your immune response.
3. Vaccination technology has an effect.
There are multiple ways to develop a vaccine. It's generally believed that live (weakened) vaccines create a more long-lasting response as they are the closest experience to real infection. However, this type of vaccine is not always the right one for a particular illness.
What's the takeaway?
Just because one vaccine provides lifetime protection, we can’t assume all do. In a nutshell, if boosters are recommended, it's because it’s the best strategy for defence against a particular virus and vaccine. Keeping our vaccinations up to date is one of the simplest, most effective steps we can take to defend ourselves against winter illness.