Very little is known about the new H1N1 pandemic virus. For example we do not know how long the virus is excreted by infected humans and how much virus is spread to surfaces and carried in the air. This is very important to know as soon as possible because it affects the advice that will be given to healthcare workers about controlling the spread of infection to themselves and other patients. Similarly we need this information so we can give good quality advice to families who will have to look after each other in their own homes.