Science by Email | Flu, Underwater plants

Science by Email | Flu, Underwater plants: "The word flu is short for influenza, which is a fairly common disease. Symptoms include fever, cough, runny nose and muscle aches. Those affected can often be sick for a week or more.

The flu is caused by the influenza family of viruses. There isn’t just one type of flu – there are many strains.

Experts believe the disease is spread by people with flu coughing and sneezing, which releases droplets including virus particles. Coming into contact with these droplets can lead to infection.

After infection with one strain, most people will develop immunity but only to that group of viruses. Influenza viruses mutate and change, rapidly creating new strains.

While most people will recover from a case of the flu, it can be fatal. Flu pandemics occur when a new flu strain spreads easily and quickly. For example, the Spanish influenza pandemic in 1918–1919 is estimated to have killed about 50 million people – more than World War I that preceded it."

Read more about influenza and try this month's At Home activity!
'via Blog this'