Coronavirus: What it does to the body

The coronavirus emerged in only December last year, but already the world is dealing with a pandemic of the virus and the disease it causes - COVID-19.

For most, the disease is mild, but some people die. 

COVID-19 is a mild infection for eight out of 10 people who get it and the core symptoms are a fever and a cough.

Body aches, sore throat and a headache are all possible, but not guaranteed.

The fever, and generally feeling grotty, is a result of your immune system responding to the infection. It has recognised the virus as a hostile invader and signals to the rest of the body something is wrong by releasing chemicals called cytokines.

This rally the immune system, but also cause the body aches, pain and fever.

The coronavirus cough is initially a dry one (you're not bringing stuff up) and this is probably down to irritation of cells as they become infected by the virus.

Some people will eventually start coughing up sputum - a thick mucus containing dead lung cells killed by the virus.

These symptoms are treated with bed rest, plenty of fluids and paracetamol.

 If the disease progresses it will be due to the immune system overreacting to the virus.

Those chemical signals to the rest of the body cause inflammation, but this needs to be delicately balanced. Too much inflammation can cause collateral damage throughout the body.

"The virus is triggering an imbalance in the immune response, there's too much inflammation, how it is doing this we don't know," said Dr Nathalie MacDermott, from King's College London.