Infographic: How does herd immunity work?

Contagious diseases, like COVID-19, spread from person to person. That means that if someone gets sick, they can pass it on to other people.

When too few people have immunity against the disease, it can spread throughout the community. This happens because most of the population is susceptible to infection, so the disease can continue to reach new people.

A tried-and-tested way to break the infection cycle is through vaccination. In the case of COVID-19, fully vaccinated people are far less likely to become infected. Essentially, they are harder to infect.

If enough people get vaccinated, then whole communities can become harder to infect, which means the disease won't be able to spread as easily.

And this ultimately protects those who do not have immunity from the disease. It's called herd immunity. By reducing the spread of infection, the harder-to-infect members of the herd help to keep more vulnerable ones safe.

Herd immunity
It means your immunity is good for your community.

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