With the arrival of winter, colds , flu , and other respiratory infections increase . It’s natural to assume that the cold is the direct cause of these ailments. In reality, the link between low temperatures and seasonal ailments is more complex and primarily involves changes in our habits and environmental conditions.
We talk about it with Dr. Michele Cerasuolo , otolaryngologist at Humanitas San Pio X and the Humanitas Medical Care medical centers.
Does the cold make you sick?
Cold, by itself, cannot cause an infection. Diseases are always caused by viruses or bacteria.
During the winter months, however, we spend more time in closed and shared environments—homes, offices, schools, public transport—where close contact facilitates the transmission of microorganisms.
Other factors contribute to the increased spread of infections:
- Dry air : typical of heated environments, it can dehydrate the mucous membranes of the nose and throat, reducing their protective barrier function.
- Less exposure to the sun : leads to reduced production of vitamin D , involved in the correct functioning of the immune system.
- Respiratory droplet behavior : In cold, low-humidity environments, respiratory particles can remain suspended longer, increasing the risk of infection.
The idea that cold weather “makes you sick” therefore arises from a misunderstanding: low temperatures do not directly cause the infection, but create conditions that facilitate its spread.
The causes of the common cold
The common cold is a viral infection of the upper respiratory tract, particularly the nose and throat. It is caused by over 200 different viruses, the most common of which are rhinoviruses .
The infection is mainly transmitted through the air, through droplets released by coughing, sneezing, or even simply by talking, or by direct contact (hands, contaminated surfaces).
Some cold viruses can survive on surfaces for several hours, making closed spaces more likely to spread. A person is generally most contagious in the first 2–3 days after the onset of symptoms.
Symptoms of the common cold
Symptoms typically appear a few days after infection. The most common are:
- stuffy or runny nose
- sore throat
- frequent sneezing
- presence of nasal mucus
- cough
- hoarse voice
- tiredness
- feeling of unease .
Sometimes they may be associated with:
- fever
- heachache
- muscle pain
- reduction of smell and taste
- eye and ear irritation .
Symptoms are most intense in the first two or three days and tend to subside within a week or so. The cough can last two or three weeks.
How to get rid of a cold?
The common cold is a self-limiting disease and in most cases resolves spontaneously within 5–10 days.
Treatment is symptomatic and may include:
- Antipyretics and painkillers for fever and pain
- Nasal decongestants to ease breathing
- Nasal washes with saline solution
Antibiotics are not effective against viruses and should only be used on medical prescription if a bacterial complication is suspected.
How to reduce the risk of infection?
Some simple measures can limit the spread of the virus:
- Staying at home in the first few days of illness
- Air out the rooms frequently
- Wash your hands often
- Cover your mouth and nose when coughing or sneezing
- Wear a mask if you experience symptoms, especially in closed or crowded environments.
If you experience persistent high fever, worsening symptoms, or difficulty breathing, you should consult your doctor for a clinical evaluation.
