Is your blood type O negative? Have you donated blood before? Are you in good health? If the answer to ALL of those questions is yes, then the NHS needs you – before Christmas.

Stocks of O negative are running low. There are about three days supply, instead of the usual five or more. Just 7% of the population are O negative, and they are often referred to as “universal donors”. That is because their blood can be given to anyone – so it is especially useful to the health service.

read the rest of the article on the BBC website