Influenza pandemic

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Pandemic flu reassortments

Influenza pandemic refers to an outbreak of influenza virus that spreads on a worldwide scale and infects a large proportion of the human population. In contrast to the regular seasonal epidemics of influenza, these pandemics occur irregularly, with the 1918 Spanish flu the most serious, killing millions of people worldwide.

History

The most famous and lethal outbreak was the so-called Spanish flu pandemic (type A influenza, H1N1 subtype), which lasted from 1918 to 1919. Other notable pandemics include the Asian Flu in 1957 and the Hong Kong Flu in 1968.

Causes

Influenza pandemics occur when a new strain of the influenza virus is transmitted to humans from another animal species. Species that are thought to be important in the emergence of new human strains are pigs, chickens and ducks.

Symptoms

The symptoms of influenza include fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, fatigue and some people may have vomiting and diarrhea.

Prevention

Vaccination against influenza with an annual flu vaccine is recommended for everyone 6 months of age and older. Antiviral drugs can be used to treat influenza, with neuraminidase inhibitors the most commonly used.

See also

• Epidemiology of influenza
• Influenza vaccine
• Influenza treatment
• Influenza research