Influenza, or simply the flu, is caused by influenza virus.
Almost everyone has had the flu at some point—high fever, runny nose, sore throat, muscle pains,
headaches, coughing, sneezing, and feeling tired—it’s terrible.
Good news is that it usually improves in a week, but occasionally someone can go from
being completely healthy to being seriously ill—requiring hospitalization or even care
in the ICU.
The flu spreads when a sick person sneezes or coughs, and sends thousands of virus-containing
droplets into the local area.
If they’re lucky, these viruses might land directly on another person’s nose or mouth,
but more often they end up landing on nearby objects like a table.
But the flu virus is hardy—and it can survive for hours in the environment.
To make matters worse, a person may be contagious a day before their symptoms even begin, and
up to two weeks afterwards—even after they feel much better!
So, while it’s great that Debbie is back to work this week after recovering from the
flu.
It’s not so great that Debbie brought contaminated doughnuts to share.
Thanks Debbie!
OK, so if you don’t want to feel like garbage with the flu for a week, or get your friends,
family and coworkers sick, the most effective way to prevent influenza is through vaccination,
which can be done as an injection or nasal spray.
These vaccines usually contain a mix of three weakened or inactivated influenza virus strains
that are predicted to be the ones that will dominate for a specific season.
And because flu viruses mutate rapidly these vaccines are updated twice a year.
So how well do they work?
Well it depends.
First, high-risk individuals like pregnant women, those with a chronic health condition,
or those under 6 months or over 65 years of age—are more susceptible to the flu despite
being vaccinated.
Second, since the vaccine is based on predictions, some years are better than others.
On average, though, the flu vaccine reduces the risk of illness by roughly half from about
10% to about 5% in terms of the likelihood of getting sick over the entire flu season.
That means that the average person may get the flu about one out of every 10 years without
the vaccine and about one out of every 20 years with the vaccine.
So, for any given year, you might decide that your risk of getting the flu is quite low
anyways so it’s not worth getting the vaccine.
But remember, the flu can do more than make you feel terrible, the flu can cause serious
injury—even death.
Also, it’s worth remembering that in the 2016 – 2017 flu season in the US—the most
recent one where we have complete data—the CDC estimates that the flu vaccine prevented
5.3 million cases of flu, 2.6 million medical visits and 85,000 hospilizations!
Getting vaccinated also decreases your chances of you passing the flu to someone else, like
Debbie with her contaminated doughnuts.
Therefore, the more people in a community that are vaccinated against flu, the fewer
people will contract and spread the flu.
This protects those that can’t get vaccinated like infants under 6 months old.
This is called herd immunity, because the herd is protecting the weakest members.
To wrap up, of course, yearly flu vaccine is recommended for everyone over six months
old, with only a few exceptions.
It’s not recommended for people with life threatening egg allergies or a history of
Guillain-Barré Syndrome.
Otherwise, since flu season generally begins in the fall and peaks in the winter, it’s
a good idea to get vaccinated by the end of October if you live in the Northern hemisphere.
That said, the vaccine still provides protection even if you get it later in the season—so
don’t let it being past Halloween or even Thanksgiving be an excuse for not getting
vaccinated.
If you’d like to learn more about the flu, check out our Influenza video on Osmosis.org.