If it seems like everyone is sick in February, you’re not imagining it. ER doctors see a surge in flu, colds, RSV, and other infections every year during this time. But why is this month particularly rough on our immune systems?
“There are a few key reasons why people tend to get sick more often in February,” says Dr. Kenter, Chief Medical Officer at Ally Medical ER. “The increased time spent indoors due to colder weather makes it easier for viruses like influenza and the common cold to spread. Additionally, lower exposure to sunlight decreases vitamin D levels, which can weaken the immune system. In addition, the stress and changes in routine associated with the holiday season can compromise immune responses, making individuals more susceptible to infections.”
How Winter Weakens Your Immune System
- More time indoors – Cold weather pushes people into close quarters, increasing the spread of viruses.
- Dry air – Heated indoor air dries out nasal passages, making it easier for germs to enter the body.
- Low vitamin D levels – Shorter days and less sun exposure can weaken the immune response.
- Lingering post-holiday fatigue – After months of stress, travel, and disrupted routines, your body may still be recovering.
- Flu season is still going strong – The flu peaks between December and March, making February a high-risk month.
Simple Ways to Strengthen Your Immune System
Keeping your immune system strong doesn’t require drastic changes—small, daily habits can make a big difference.
- Stay hydrated. Dehydration weakens your immune function. “Many people don’t drink enough water,” says Dr. Kenter. “In the winter, your body still needs just as much hydration as during the rest of the year to fight off illness.”
- Eat nutrient-rich foods. Vitamins and antioxidants play a significant role in immune function. Foods rich in vitamin C, zinc, and probiotics (like citrus, leafy greens, yogurt, and nuts) help strengthen your body’s defenses.
- Get enough sleep. “Your immune system recharges while you sleep,” Dr. Kenter explains. “Not getting at least 7–9 hours per night can leave you more vulnerable to infections.”
- Wash your hands regularly. Proper handwashing can reduce the spread of viruses by nearly 50%.
- Take time to rest. Chronic stress weakens the immune system. “Stress hormones like cortisol can suppress immune function, making it harder for your body to fight off infections,” says Dr. Kenter.
When to Seek Medical Attention
Not every illness requires a trip to the ER, but some symptoms shouldn’t be ignored. Seek emergency care if you experience:
- A fever over 103°F that doesn’t improve with medication
- Severe dehydration (dry mouth, dizziness, or no urination for 8+ hours)
- Difficulty breathing or chest pain
- Flu or cold symptoms that worsen instead of improving after a few days
“Your immune system is constantly working to keep you healthy, but it also needs support,” says Dr. Kenter. “The best thing you can do is listen to your body, rest when needed, and seek medical help when symptoms become severe.”
We’re Here When You Need Us
If you’re feeling unwell and need fast, expert care, Ally Medical ER is open 24/7 with little to no wait times. We have eight locations across Austin and Houston, ready to provide emergency care when you need it most.
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Dr. Jeremy Kenter, Chief Medical Officer