What Is a Cold?

Common cold is the most frequent infectious disease in humans. The average adult contracts two to four infections a year and the average child contracting 6-12. Therefore it is no surprise that common colds are the most common reason that children miss school and parents miss work. In fact there are over one billion colds in United States alone each year.

Common cold is a viral infectious disease of the upper respiratory system. It is primarily caused by rhinoviruses and coronaviruses. A cold virus spreads mainly through tiny air droplets that are released when sick person sneezes, coughs or blows their nose. You can also catch a cold if you touch your nose, eyes or mouth after touching contaminated surface such as a doorknob. However exposure to a virus does not mean that exposed person will definitely fall sick.

Cold symptoms usually occur within 2 to 3 days after the contact with the virus, although in some cases it might take up to a week. The common cold is most infectious during the first two to three days of symptoms and usually is not contagious after the first week.

The most common cold symptoms are:

  • cough
  • sore throat
  • runny nose

These symptoms are often accompanied by muscle aches, fatigue, headaches, shivering and loss of appetite. Also mild fever is often present thus creating a symptom picture which overlaps with influenza.

The common cold is self-limiting – healthy immune system effectively deals with the infection. The symptoms usually resolve spontaneously in 7 to 10 days but can in some rare cases up to three weeks. In children it is not rare that the cough can last more than 10 days.

Even though there are currently no specific drugs against common cold, there are ways to prevent getting sick in the first place and measures that can be taken to ward of the infection when symptoms starts occurring.  There are also many ways to get relief to symptoms if you do get sick.

What is the difference between a common cold and flu?

Common cold is often confused with flu as they share some of the same symptoms especially in the early stages of infection. However, the two diseases are very different. Symptoms of flu usually start very suddenly, after two or three days of the contamination. Usually the first symptoms are chills or chilly sensations but also high fever (38-39°C or 100-103 °F) is very common already early in the infection. Other symptoms of influenza include:

  • cough
  • body aches, especially joints and throat
  • fatigue
  • headache
  • Irritated, watering eyes

In children symptoms such as diarrhea and abdominal pain may occur.

Influenza can be very rough – many people are so ill that they are confined to bed for several days, with aches and pains throughout their bodies. Influenza can also cause possible complications like pneumonia, encephalitis (infection of the brain), bronchitis, sinus infection and ear infection.

For more details about differences between common cold and flu, please see table below.