🍂 Why Do We Get Sick in the Fall and Winter?
Fall Sick Series | Week 1 – Varrock Street Journal
Welcome to the Fall Sick Series
Hello Varrock Street Journal community!
As the leaves begin to fall and the air turns crisp, a familiar pattern sets in — sniffles, coughs, and fevers. Why is it that just as the world around us prepares for rest, our bodies seem to go under viral siege?
This week, we’re launching a new Fall Sick Series to explore why illness thrives in the colder seasons, and what that means for your health, your community, and our understanding of infection. From the science of viral spread to the biology of immune function, this series will dig into why fall and winter feel like flu season — and how much of it is preventable.
Why Do We Get Sick More in Fall and Winter?
The truth is, cold weather doesn’t cause illness — viruses do. But the conditions that come with cooler temperatures make it much easier for them to spread.
Here are the main reasons:
🧊 Drier Air = Easier Spread
Cold air holds less moisture. This dries out the mucus membranes in your nose and throat — the body’s first defense against airborne viruses — and helps respiratory droplets remain suspended in the air longer, increasing the chance of transmission.
🏠 We Stay Indoors
As the weather cools, we spend more time indoors, in closer proximity to others. Poor ventilation, shared surfaces, and recycled air all contribute to higher exposure.
🧬 Viruses Live Longer in Cold Temps
Influenza and other viruses remain more stable and infectious in lower temperatures and low humidity, allowing them to survive longer on surfaces and in the air.
😴 We’re Immunologically Vulnerable
Less sunlight means lower vitamin D levels, which can weaken immune responses. Add seasonal stress, poor sleep, and dietary changes, and your immune defenses may not be operating at full strength.
Why This Matters
Understanding why we get sick during certain seasons isn’t just trivia — it helps guide public health strategies. From when we roll out flu shot campaigns, to how we build schools and homes with ventilation and exposure in mind, this science informs real decisions.
It also empowers individuals to take early precautions: improve sleep, boost vitamin D, maintain hand hygiene, and avoid crowded indoor events during peak respiratory virus seasons.
Here is a fun video going over what we talked about today!
Spotlight on Future Applications
Some researchers are exploring UV-based air sterilization for indoor spaces, while others are building "smart HVAC" systems to control humidity and pathogen circulation.
Public health teams are also looking into seasonal illness prediction models, combining weather data, mobility patterns, and virus surveillance to forecast and contain outbreaks — much like we predict hurricanes or wildfires.
Reflection Questions
- What parts of your routine could you adjust to reduce your exposure to respiratory viruses in colder months?
- Should we rethink public building design for better airflow in winter?
- Is there a way to make illness prevention a seasonal habit, like putting on a coat?
📚 Sources
- National Institutes of Health. (2020). Why flu season occurs in winter.
- Moriyama, M., Hugentobler, W. J., & Iwasaki, A. (2020). Seasonality of respiratory viral infections. Annual Review of Virology.
- CDC. (2023). Flu & Cold Season Trends.
- Yale School of Medicine. (2022). Why cold air increases virus spread.