The common cold occurs due to infection of the upper respiratory tract (nose, throat, and sinuses) by certain viruses, most commonly rhinoviruses. It is a highly contagious condition and spreads easily from person to person. Below are the major causes and contributing factors:
Viral Infection
Rhinoviruses: Cause the majority of common colds.
Other viruses include:
Coronaviruses (non-COVID types).
Adenoviruses.
Parainfluenza viruses.
Respiratory syncytial virus (RSV).
These viruses infect the lining of the nose and throat, causing inflammation and triggering cold symptoms.
Spread of Infection
The viruses spread through:
Airborne Droplets:
Sneezing or coughing releases tiny droplets containing the virus.
Inhaling these droplets can infect others.
Direct Contact:
Touching a person who has the virus (e.g., shaking hands) and then touching your face.
Contaminated Surfaces:
Viruses can survive on surfaces like doorknobs, mobile phones, and tables.
Touching these surfaces and then touching your mouth, nose, or eyes can lead to infection.
- Risk Factors
Certain factors increase the likelihood of getting a common cold:
Weakened Immune System:
Due to fatigue, stress, or underlying illness.
Close Contact:
Crowded places like schools, offices, or public transport.
Cold Weather:
More indoor gatherings and drier air during winter help viruses spread.
Age:
Young children are more susceptible due to immature immune systems and frequent contact with peers.
Allergies or Sinus Problems:
Can make the nasal passages more prone to infection.
- Environmental Factors
Dry Air:
Dries out nasal passages, making them more vulnerable to viral invasion.
Seasonal Patterns:
Cold and flu viruses are more active in colder months.
- Lack of Hygiene
Poor handwashing practices can facilitate the spread of cold viruses.
Why Does It Happen Repeatedly?
There are over 200 viruses that can cause the common cold.
Immunity to one virus doesn’t protect you from others.
Even immunity to the same virus fades over time, allowing reinfection.
While the common cold is not serious, practicing good hygiene, avoiding close contact with sick individuals, and maintaining a healthy immune system can help reduce the risk of getting infected.