Everything you need to know about the flu
A common misconception is that influenza is the same as the stomach flu
In Canada, it’s estimated that each year the flu is responsible for about 3,500 deaths and 12,000 hospitalizations. Here’s everything you need to know about the pesky virus.
WHAT IS THE FLU?
Influenza, commonly called the flu, is a viral infection that attacks the respiratory system. It has an incubation period of up to four days — which means you could be harbouring the virus for several days before you know you’re sick — with symptoms usually lasting from five to fourteen days.
The symptoms include a fever higher than 38 degrees Celsius, aching muscles, chills and sweats, headache, dry cough, fatigue, runny or stuffy nose, and a sore throat. Although the flu is often confused for the common cold, the former comes on very suddenly, lasts longer, and typically makes you feel much worse.
A common misconception is that influenza is the same as the stomach flu. But the latter — medically known as gastroenteritis — refers more generally to a variety of bacteria, viruses, and parasites that can upset your stomach. And while influenza can sometimes lead to vomiting and diarrhoea, these are uncommon symptoms in adults.
WHEN IS FLU SEASON?
Flu season typically starts in October and peaks from December until the end of March, sometimes lasting until May. Although it’s not entirely clear why prevalence is highest during the winter months, research has come up with some possible explanations. The first, is the virus might thrive in cooler temperatures and low humidity, both cornerstones of the winter season. Once the weather turns cool, people tend to spend more time indoors in closer proximity to one another which could make it easier for the virus to spread. The lack of sunlight during the winter months also reduces levels of vitamin D and melatonin, which in turn can compromise immune systems and make it harder for us to fight off the virus.
WHO IS AT RISK AND WHAT ARE POTENTIAL COMPLICATIONS?
Although anyone can catch the flu, there are certain groups that are more vulnerable to infection. Adults over 65 and children under five, pregnant women, people with chronic illness, people living with obesity and those who have weakened immune systems are all more susceptible. People living in nursing homes and other long-term care facilities are also more likely to catch the flu.
The flu can potentially cause implications, especially among higher risk individuals, such as bronchitis, pneumonia, and ear and sinus infections. It can also worsen existing chronic conditions, such as diabetes and asthma.
WHAT CAN YOU DO TO PREVENT THE FLU?
The best line of defence against the virus is the flu shot, which is recommended for everyone except babies under six months old.
Every year researchers determine which strains of the virus are expected to be most prevalent and design the flu shot for these strains. This — along with the fact that protection from vaccination declines over time — is why it’s recommended that people receive a flu shot annually.
There are many misconceptions when it comes to the flu shot, one being that it can actually give you the flu. The vaccine is made from dead strains of the virus, so you can’t get sick from the shot itself. But it’s possible to get mild symptoms as a reaction to your body building up an immune response. You can also still contract other strains of the flu that aren’t protected against by the vaccine. This year, the flu shot is protecting against two strains of Influenza A (H1N1 and H3N2) and Influenza B.
Another misconception is that people who are healthy and have never had the flu before shouldn’t get the shot. People with a strong immune system can harbour the virus without having any symptoms, but during this time the virus can still be passed on to someone else who might not be so lucky.
Aside from getting the flu shot, there are other simple steps to prevent the flu’s spread. Washing your hands regularly, disinfecting common surfaces like doorknobs and light switches, and coughing and sneezing into your shirt sleeve rather than your hands are all recommended. If you’ve had the flu, staying home from work or school until at least 24 hours after your fever subsides can lessen the chance of you infecting others. Eating healthy foods, staying active and getting enough vitamins to keep your immune system strong are also good steps to take to keep the flu away.
HOW DO YOU TREAT THE FLU?
Most people are able to fight off the flu with some rest and lots of fluids. There are also three approved antiviral medications in Canada that can be prescribed by a doctor for people at high risk, or those who are struggling to fight the virus off on their own.
People who are considered high risk should see their doctor at the first signs of the flu. Those who do not fall into this category should only see their doctor if symptoms persist for more than two weeks, their fever gets better and suddenly worsens, or pain becomes concentrated in one area.
An emergency room visit is a good idea if you’re having chest pain or difficulty breathing, sudden dizziness, or persistent vomiting.
The Canadian government provides weekly updates on the virus here throughout flu season.