- Once people have had some viral infections, like chickenpox, it makes them immune from having it again – vaccination creates the same kind of immunity, so can prevent people from getting the viral infections.
The more people who are vaccinated reduces the amount of infection in a population, protecting even those people who are not vaccinated – this is called ‘herd immunity’. Depending on the virus, 85-95% of people need to be vaccinated to protect the rest of the people – this is why vaccination is important.
- Viruses are passed on by sneezing and coughing, or by touching someone who has a viral infection – this is why it is important to cough or sneeze into tissues and wash hands regularly when infected with a cold or other viral infection.