Types of Flu
We know the symptoms of flu — cough, sore throat, fever and chills — but do we know what type of virus we’re dealing with? According to medical experts, understanding the different viruses can be life-saving.
Here are some of the perpetrators that make us feel stuffed up on a bad day:
A viruses are common among humans and animals and may be responsible for new pandemics as they evolve new strains. They are further classified by subtypes based on their surface proteins.
B viruses similarly cause the annual seasonal flu like the A viruses, but they only affect humans. Like the A viruses, new strains also cause pandemics.
C viruses are not as common as the A and B variants and are not related to the seasonal flu. However, vaccines against influenza A and B do not protect against C viruses.
Aside from the types of known influenza viruses, we also need to understand how a new virus evolves. Some viruses start in animals and then make their way into humans.
Strains from influenza A and B are what cause the seasonal wave of flu. These cause the following symptoms:
- fever and chills
- sore throat
- coughing and wheezing
- body aches
The symptoms of the flu can last for one to two weeks. The seasonal flu is highly contagious and can spread via small droplets transported in the air.
Swine Flu (H1N1)
The H1N1 virus was first discovered in 2009 and is a relatively new strain that infects humans. It was called ‘swine flu’ because it started in pigs. Those infected showed the same symptoms as those who have the seasonal flu.
The virus caused a pandemic in 2009 and 2010 because there was no flu shot developed yet. Today, seasonal flu shots now also protect against H1N1 viruses.
The ‘bird flu’ is a strain of A virus that starts in birds. According to reports, the H5N1 strain which started in poultry has so far cost 600 human lives. This strain is believed to be passed from birds to humans but not between humans.
H7N9 is another strain that has caused severe respiratory infections and deaths in China. There are no reports of the virus occurring elsewhere, but we can never be sure where the virus can evolve.
Pandemics happen when new strains evolve that cannot be combatted by current flu shots. They mostly occur when influenza A strains evolve and infect humans.
Lack of protection from the new strains makes humans more vulnerable to pandemics. The last time a pandemic hit was in 2009 with the swine flu.
Despite the severity of pandemics, American health website Flu.gov said they happen rarely. The group estimated that only three pandemics occurred during the 20th century. However, to protect yourself during a pandemic, it is advisable not to travel and to practice good hygiene habits.
Flu viruses constantly change, developing new strains that may hit humans. This phenomenon is called the antigenic drift. This is why flu shots contain protection for different strains every year.
Some viruses become dormant and reappear in the future. Getting the annual flu shot and practicing safe hygiene can protect you from being infected.