Considering how common they are, colds and flu are the subject of a great many misconceptions. Dr. Seth Feltheimer, an associate attending physician and Patricia Ciminera, nurse practitioner at NewYork-Presbyterian Hospital/Columbia, offer their insights and expertise on these sources of misery.

First of all, the differences: a cold is usually an upper respiratory tract infection with symptoms including a sore throat, head congestion, sinus pain, and low-grade fever. On the other hand, the flu is generally marked by a higher fever, a sore throat, a cough, and body aches. A common cold usually lasts two to three days while the flu can take as long as a week Unlike colds, the flu can lead to more serious complications and even hospitalization, especially in high-risk individuals like asthmatics and the elderly.

Now, the facts and fictions:

• "The best way to prevent a cold is to wash your hands."
  Fact. Also, try avoiding people with colds.

• "You can catch a cold by staying outside in the cold too long."
  Fiction. Colds are transmitted by touching something that an infected person has touched, or by breathing in moisture that an infected person has coughed out. The reason people get more colds in winter is that they spend more time indoors and have more contact with each other.

• "Antibiotics can cure a cold or the flu."
  Fiction. A cold or flu is a virus, and, therefore, cannot be treated with antibiotics. There are medications that can alleviate the symptoms of flu and make you feel better, but the best defense against the flu is to be vaccinated against it. There is no vaccine against the common cold.

• "If you have the flu, you shouldn't go to work."
  Fact. Going to work can expose your colleagues to infection. Sometimes, professional athletes play with the flu, but in those cases it is usually a different virus involved. The best advice is to rest and recover.

• "Flu shots can give you the flu."
  Fiction. Flu shots can produce very mild flu-like symptoms for a short period, but this happens very infrequently.

• "If you have a flu shot one year, you don't need it the next."
  Fiction. Flu shots do not last for more than a year. And, the vaccine is reformulated each year to target the specific kind of virus, which may change from year to year.

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