1. An infected person sheds mucus from their nose and throat and the virus is aerosolised by speaking, sneezing and coughing. You breathe the virus into your respiratory system.

2. It can be left on hands, surfaces and objects such as handkerchiefs. These items then come into contact with your nose or mouth. This is possibly the most important way the virus is spread, and all must be done to prevent it from spreading this way. The importance of handwashing cannot be stressed enough.

3. You can be infected via the air, or via an infected object touching your nose or mouth.

The highest rates of infection are seen in children in créches and schools.