What is the Difference Between the Flu and a Cold?

Influenza, commonly called the flu, is contracted in the same way that a cold is, and, like a cold, is a seasonal illness caused by a virus. However, although both conditions can share some similar symptoms, they are very different illnesses. Generally speaking, a cold is less serious.

Elderly people or people with chronic diseases are at risk for developing complications from the flu such as pneumonia. Pneumonia can cause death in those over 65 years of age and is problematic for those with heart disease, asthma or compromised immune systems. Flu shots are often recommended as an effective way of preventing death and serious complications. The vaccines are said to be 70% effective, but must be administered each year as the strains of influenza viruses are ever-changing.

Hand-washing, especially with antibacterial soap, is often a good way of preventing both the flu and a cold as both viruses are transmitted through droplets from sneezes and through contact with droplets on surfaces. Viruses can live on surfaces for a few hours and can be transmitted by touching an infected surface and then touching eyes, nose, or mouth areas. Avoiding touching the face, hand-washing and sneezing into facial tissue followed by hand-washing are some good preventive steps in avoiding transmission of both illnesses.

A big difference between the flu and a cold is in the onset of the illnesses. Cold symptoms usually appear much more gradually than flu symptoms. A person just getting the flu can feel fine one minute and then come down with a fever and chills the next. Contrastingly, a cold can begin with sneezing or a slightly runny nose for a few days before much stronger symptoms appear.

Additionally, colds do not cause a feeling of physical exhaustion like the flu can. People with a cold may feel less energetic than usual for a day or two, but fatigue from influenza can be severe and last a few weeks. Muscle aches and headaches also tend to be less severe in cold sufferers.

While flu sufferers tend to experience symptoms in many areas of the body, cold sufferers tend to experience symptoms relating to the nose. Sneezing, and/or a runny or congested nose are common cold symptoms. While people with the flu may develop a fever, lethargy, aching all over and vomiting and/or dizziness early on, after a few days the symptoms are likely to change to a sore throat and cough. Though this can also happen with a cold, those with a cold usually do not have redness of the throat, and often have a wetter, milder cough.