Why Do People Catch Colds in the Summer?

 

Coughing, sneezing, and sore throats in the middle of summer? You're not alone. Despite the old saying, "Even dogs don’t catch colds in summer," summer colds have become surprisingly common these days.

Let’s take a closer look at why summer colds happen, and how you can protect yourself — especially with the help of drug-free nasal sprays that contain carrageenan, a natural antiviral ingredient.

What Causes the Common Cold?

The common cold is primarily caused by viral infections. The most common cold viruses include:

• Rhinoviruses – responsible for about 50% of all colds

• Coronaviruses – a known cause of colds even before COVID-19

• Adenoviruses and parainfluenza viruses – also contribute to cold symptoms

These viruses invade the mucous membranes in the respiratory tract, triggering inflammation and various cold symptoms.

When Are You More Likely to Catch a Cold?

Cold viruses are constantly around us, but certain conditions increase your risk of infection:

• Weakened immune system
  Lack of sleep, chronic stress, and overexertion can reduce your body’s defenses.

• Sudden temperature changes
  A drop in temperature, especially during seasonal transitions, weakens the nasal lining and its ability to block infections.

• Close contact in enclosed environments
  Offices, public transport, and schools make it easier for viruses to spread through coughs or sneezes.

• Poor hand hygiene
  Touching your eyes, nose, or mouth with contaminated hands can lead to infection.

Why Do People Get Sick More Often in Cold Weather?

While viruses are the root cause, cold weather makes it easier for them to take hold:

• Reduced defense in nasal membranes
  Cold air lowers blood flow and immune cell activity in the nose, allowing viruses to enter more easily.

• Dry air favors virus survival
  Winter air is dry, especially indoors with heating, helping viruses stay airborne longer. Dry air also cracks mucous membranes, making them more vulnerable.

• Increased indoor gathering
  Cold weather means more time indoors, where airborne viruses spread more easily.

• Decreased sunlight exposure
  Less sunlight in winter reduces vitamin D production, which can lower immune function.

Then Why Do We Catch Colds in the Summer?

Summer brings its own set of risk factors that can weaken your immune defenses:

• Drastic indoor/outdoor temperature differences
  Air-conditioned spaces often stay at 68–73°F, while outside temperatures exceed 86°F. These sharp temperature shifts weaken the nasal mucosa and make it easier for viruses to take hold.

• Weakened immune system
  Disrupted routines from vacations, late nights, or poor hydration can lower immunity and increase susceptibility.

• Humid outdoors, dry indoors
  Although summer is humid outside, air conditioning dries out indoor air. Dry nasal passages are more vulnerable to viral invasion. Rainy seasons also increase the presence of mold, bacteria, and viruses.

Is It a Summer Cold or "Air Conditioner Syndrome"?

“Air Conditioner Syndrome” isn’t a medically defined disease, but rather a collection of symptoms caused by poor adaptation to artificial indoor environments.

Common symptoms include:

• Respiratory symptoms
  Runny or stuffy nose, sneezing, fatigue, headaches, and even body aches.

• Digestive discomfort
  Indigestion, stomach discomfort, and diarrhea — especially among those who are sensitive to cold.

Although these symptoms may resemble a viral cold, the underlying cause is physical stress from cold and dry environments.

How to Prevent Summer Colds

• Set indoor temperatures between 75–78°F and avoid direct exposure to air vents

• Wash your hands and brush your teeth after returning from outside

• Stay hydrated and get enough sleep

• Clean air conditioner filters regularly

• Be cautious about viral exposure at pools or crowded indoor areas

Additional Tip: How Carrageenan Nasal Sprays Can Help

One overlooked way to protect your nasal health during summer is by using a carrageenan-based nasal spray. Carrageenan is a natural extract derived from red seaweed, known for its antiviral and moisturizing properties.

How it works:

• Forms a physical barrier in the nasal passages that traps and deactivates viruses

• Helps keep nasal tissue moist and resilient, even in dry air environments

• Safe for regular use, drug-free, and suitable for both adults and children

Nasal sprays with carrageenan can be especially helpful if you're exposed to air conditioning for long hours, traveling, or spending time in crowded places.

Stay Healthy This Summer

Summer colds may not seem serious at first, but they can disrupt your routine just as much as a winter illness. By managing your indoor environment, taking care of your immune system, and using protective nasal sprays, you can stay healthy and comfortable all summer long.