When is Cold and Flu Season

As the leaves change and the air turns crisp, we welcome the comforting embrace of sweater weather and warm drinks.

Unfortunately, sweater weather also signals the start of cold and flu season. Read on to learn when cold and flu season peaks and the most effective ways to protect yourself and your loved ones, so you’re focused on the beauty of the season and prioritizing your well-being. 

What is cold and flu season?

The difference between cold and flu

Colds and the flu are both caused by viruses. And, while there is some overlap in their symptoms, the flu is generally more severe.

The hallmark of the flu is its sudden onset. Within a few hours, you can go from feeling fine to experiencing fever, chills, and headache. This is often why you can fall asleep feeling healthy, only to wake up in the middle of the night feeling miserable and achy.

In contrast, colds are generally slower to arrive. Similarly, their symptoms aren’t usually as severe — though the sore throat, runny nose, and chills they may cause can still be pretty uncomfortable.

While both can cause milder symptoms like coughing to linger for up to three weeks, most healthy people can expect to recover from either a cold or the flu within seven to 10 days. 

Factors that contribute to the season

As the weather cools down, we naturally spend more time indoors, often surrounded by others. With everyone gathering inside, it becomes easier for germs to circulate from one person to the next.

Beyond the close quarters, the cold itself can play a role. The cells lining your nasal passages, which are part of your body’s first defense against infections, don’t work as efficiently in colder temperatures, making it harder for your immune system to respond quickly to viruses.

Timing of cold and flu season

Colds and flu are both caused by viruses that circulate in the population throughout the year. So, while you’re less likely to come down with a case of the flu when it’s 30°C outside, it can still happen.

However, both viruses take off when the temperature drops and large groups of people gather together indoors. As a result, cold and flu season picks up steam as fall wraps up. And, if the conditions are right, it can last until spring. This often means that you’re most likely to come down with a cold or the flu between November and March.

Peak times and duration of cold and flu season

Identifying the peak of flu season

Cases of cold and flu tend to be higher from October to November until March or even April. In spite of this, cases most often peak between December and February.

However, not every year follows the same pattern. For example, public health data shows that Canada saw the highest rates of flu between November 27 and December 3 for the 2022 to 2023 season, which is earlier than typical. For the 2023 to 2024 season, we saw a return to more normal timing, with a peak in cases coming in the final week of December.

Factors affecting cold and flu season

Multiple factors influence how long cold and flu season lasts and how bad it gets. These include:

• Vaccination rates

The flu vaccine reduces your chances of getting the flu and helps to prevent severe illness if you do contract it. Being vaccinated also makes you less likely to transmit the influenza virus to others.

• Efficacy of this year’s vaccine

The flu virus mutates over time, which means that each year’s variant is different from the previous year’s. Scientists do their best to match the vaccine to the flu strains currently circulating, however, it isn’t always perfect. As a result, rates of infection can vary depending on how effective that year’s vaccine is.

• The transmissibility of this year’s strain

Different mutations in the flu virus can affect how easily it spreads from person to person. As a result, some years see longer seasons while others have a milder, shorter cold and flu season.

How does climate impact cold and flu season? 

Warmer winters often result in more mild flu seasons. For one, higher temperatures mean that your body can mount a more effective defense against viruses. Additionally, people are more likely to spend time outdoors, decreasing opportunities for viral spread and resulting in fewer infections.

While this may seem like a nice benefit, it may actually increase flu cases in future years. Fewer flu infections means less natural immunity in the population. As a result, the following winter can often see an early and more severe flu season.

Prevention strategies for cold and flu season

While you can’t prevent the flu entirely, you can reduce your risk of getting sick. Here’s how:

Practice proper hand hygiene

The influenza virus can survive up to 48 hours on some surfaces, turning the office fridge handle or the keyboard at a shared workstation into potential sources of contamination.

Luckily, washing your hands with soap and warm water for 20 seconds — as long as it takes to sing happy birthday twice — can effectively prevent the spread of germs. If soap and water aren’t available, hand sanitizer is a great alternative — provided it has an alcohol concentration of at least 60%.

Flu vaccination

Health Canada recommends that almost all Canadians get a yearly flu vaccine. The flu virus changes every year and several strains are often circulating at the same time. As a result, the flu vaccine is adapted each year to correspond to the strains scientists think will be going around.

Despite these efforts, the vaccine isn’t always a perfect fit. However, while it can’t completely prevent the flu virus, the vaccine does prime your immune system to react to it. That means that if you do get the flu after being vaccinated, your immune system will respond more quickly to infection, helping to shorten both the severity and duration of your illness.

How cold and flu season interacts with other health concerns

The impact of COVID-19 on flu season

Differentiating between a cold and the full-blown flu can be difficult enough. Throw in COVID-19 and it can become even harder to figure out what you’re dealing with. Worse, it’s also possible to come down with both illnesses at the same time.

In years where both are severe, this can lead to an increase in strain on our public health system. Thankfully, you can help prevent this double whammy by getting vaccinated against both the flu and the coronavirus that causes COVID-19. In fact, you can even receive both at the same time.

Seeing a doctor for a cold or the flu

While most colds and flu are easy to treat at home, if your symptoms become more severe, you may need to see a doctor. If you want to avoid the waiting room while you’re sick, consider reaching out to a primary care provider on Maple. They can discuss your flu symptoms 24/7/365 in minutes over secure text, audio, or video call.  

Primary care providers, like doctors and nurse practitioners, on Maple can recommend treatment options. If appropriate, they can provide you with prescription antivirals at their discretion to help shorten the duration of your illness. 

By knowing when cold and flu season peaks and taking proactive steps to protect ourselves, we can enjoy all that this season has to offer without the worry of illness. Remember, small actions —  like getting vaccinated, washing hands regularly, and maintaining a healthy lifestyle — can make a significant difference in keeping you and your loved ones safe

The information presented here is for educational purposes and is not meant to replace the advice from your medical professional. Virtual care is not meant for medical emergencies. If you are experiencing an emergency like chest pain or difficulties breathing, for example, please call 911 or go to your nearest emergency room.