Daily Archives: January 26, 2026

Colds and the flu are caused by viruses, not by cold wintery conditions. Viruses such as rhinoviruses, which cause the common cold, and influenza viruses spread from person to person through respiratory droplets or physical contact, regardless of the temperature outside.
However, weather and climate do play a role in why colds and the flu are more common in winter though. The colder temperatures associated with winter affect how viruses behave in the environment. Winter’s colder temperatures and lower humidity help viruses survive longer and spread more easily. Research studies show that many respiratory viruses survive longer and remain infectious for extended periods of time in cold, dry environmental conditions.
Dry air also causes tiny droplets released when people breathe, talk, cough, or sneeze to evaporate quickly. These droplets evaporate quickly, creating smaller particles that stay suspended in the air longer and travel farther, increasing the chance that others will inhale them.
Winter’s low humidity can dry the lining of one’s nose and throat. This reduces the effectiveness of mucus, which normally traps viruses and helps move them out of the airways.
In cold weather, social events tend to be indoors, bringing us in close contact with others. This increases the chance of the spread of a virus.
Preventive measures such as vaccinations, good hygiene practices, and wearing masks in crowds help to reduce the risk of viral infections. Improving indoor ventilation and maintaining adequate humidity during winter can also reduce transmission risk. Cold weather can be challenging for people with existing respiratory conditions such as asthma. Continue reading →