Colds and influenza (flu) are both extremely common infections. However, colds are hundreds of times more common than flu, except during flu epidemics. These illnesses share many features: both are caused by viruses, are highly contagious, involve the respiratory tract, and have a fairly predictable seasonal pattern.Because of these similarities, the terms “cold” and “flu” are often used interchangeably. However, there are important differences between these two types of infections, particularly in terms of prevention, severity and treatment.

What is a cold?

A cold is a minor infection of the nose and throat that lasts from a few days to a few weeks. Five different families of viruses cause colds. Because so many different viruses can cause this infection, it is unlikely that there will ever be a vaccine to protect people from catching all of the viruses that cause colds.

No Virus, No Cold

In order for a person to catch a cold, a cold-causing virus must first come in contact with the lining of the respiratory passages. Viruses that touch the lining of the eyes or mouth can make their way to the nose. In some cases, viruses can travel through the air: a person with a cold sneezes, propelling droplets of mucus and virus particles into the air, and then a second person breathes this air in, allowing the virus to become attached to the lining of the nose. Cold viruses can also be picked up from the surfaces of objects, so touching an object that has been handled by someone with a cold and then touching one’s face could also lead to a cold.


Almost everyone is familiar with cold symptoms. These symptoms usually develop anywhere from a day to a week or so after the virus enters the body. The symptoms of the average cold last about one to two weeks.

  • People generally complain of increased nasal discharge ( a runny nose), difficulty breathing through the nose, sneezing, a scratchy throat and cough.
  • The ability to taste and to smell may be affected, hoarseness may develop and voice often develops a nasal quality.
  • Adults may experience a slight fever, while infants and young children may develop a higher fever.

(For symptoms of influenza, please see “Influenza”.)


  • If possible, avoid close contact with people who have a cold, especially during the first three days when they are most likely to spread the infection.
  • Wash your hands often, especially after touching the skin of someone who has a cold or after touching an object that they have touched.
  • Keep your fingers away from your nose and your eyes.

Is it a Cold or the Flu?

Sign and Symptoms



Onset Sudden (within a few hours) Gradual (over a day or two)
Fever Characteristic, high (over 101°F) Occasional
Cough Nonproductive; can become severe Hacking at first, later may be productive
Headache Prominent and often severe Frequent and usually less severe
Myalgia Usual; often severe Slight
Fatigue; weakness Can last up to 2-3 weeks Very mild
Extreme exhaustion Early and prominent Seldom
Chest discomfort Common Mild to moderate
Stuffy, runny nose Occasional Very common
Sneezing Occasional Usual
Season Most cases between November and February All year round, with peak in the winter
Severity Severe illness, especially in first 2-4 days Mild to moderate illness


The treatment of "colds" without complications is aimed at the most prominent symptoms at the time (Please see "Antibiotics" as to why they are not  used for uncomplicated colds & flu).


Symptoms They Treat

  Tylenol, Bayer, Anacin, Motrin IB, Advil
Headaches, minor aches and pains, fever
  Sudafed, Privine, Afrin, Neo-Synephrine
Nasal congestion, sinus pressure and sinus congestion
Antihistamines (may cause drowsiness)
  Dimetapp Chlor-Trimeton, Tavist-1, Benedryl
Runny nose, watery eyes
Cough Suppressants—
  Robitussin DM
  Robitussin (various preparations)
Local Anesthetics—
  Cepacol, Sucrets, Cepastat Lozenges
Sore throat


Cold are self-limited. In other words, they always get better, with or without medication, within a few weeks. However, the cold viruses can affect the lining of the upper respiratory system in a way that leads to other infections, such as bronchitis, sinusitis, and ear infections.

  • Seek medical attention if you have: a temperature over 101F for more that 48 hours.
  • a cough associated with pain in the chest. shortness of breath (which is different from a stuffy nose).
  • persistent sore throat, especially without the runny or stuffy nose typical of a cold.
  • an extremely red throat.
  • no improvement within 7 days.
  • severe headache with a fever.
  • worsening pain in one or both ears.
  • any chronic medical condition, such as asthma or diabetes, which may complicate a cold.

REFERENCES: Guidelines for the prevention/treatment of Influenza and The Common Cold, Amer. Lung Assoc. 10/97