Flu is a common disease and thoroughly unpleasant but there are a lot of different types. Even when we hear of an outbreak of seasonal flu, it can still be one of several different viruses circulating at any one time. Here are some of the most common flu virus:
Seasonal flu
This is a type of flu that circulates for several months each year and varies depending on where in the world you are. Seasonal flu can be one or all of the three main types of influenza – A, B or C. If you want to help in the struggle to find a more effective treatment for diseases like flu, consider taking part in Paid Clinical Trials at a site like https://www.trials4us.co.uk/.
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Influenza A
Type A influenza is the most common type that causes seasonal outbreaks. It occurs in both people and animals and can be spread by people who are already infected touching items, from being close to someone who is infected and through sneezes or coughs. Influenza A is further separated into sub-sets, including strains N and H, and there are even subsets of those strains!
Influenza B
It is another virus that is responsible for many outbreaks worldwide yearly. It only appears in humans and can be very dangerous, although technically not as severe as Type A. It does not cause a pandemic, and while there are different strains of the virus, it is not broken down into different subtypes.
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Influenza C
It is the only other human virus that is less severe than type A and B. Patients may complain of mild respiratory problems. Type C does not cause pandemics and symptoms are close to those of a cold.
When flu outbreaks become pandemics
A pandemic is a disease outbreak that spreads quickly between people across the world and affects very large numbers. The line between a pandemic and a smaller epidemic is not always easy to draw, but small clusters of cases that do not pass readily from person to person are not considered pandemics.
Flu has caused several of the most serious examples. The 1918 to 1919 outbreak, often called Spanish flu, infected around 500 million people and killed more than 50 million worldwide. In 2009 the World Health Organization declared the H1N1 virus a pandemic because of how quickly it spread.
Several factors raise the risk of new pandemics, including global population growth, changes in how land is used and increasing contact between people and animals. The wider costs often come less from treatment than from disruption, as illness and fear of infection keep people away from work, close workplaces and interrupt transport and trade. Preparedness and limiting early spread are now a focus for public health planning.