Ah-choo! You’re bound to hear that sound — along with sniffling, coughing, and nose-blowing — every winter when cold-and-flu season sprinkles its misery on just about everyone. Up to 20% of Americans get the flu every year, and Americans suffer one billion colds. Children get colds and the flu more often than adults. Some kids get as many as 12 colds a year, while adults average 2 to 4.
With your chance of getting a cold or the flu so high, this Harvard Medical School Guide will surely come in handy. This report will show you how to avoid getting colds and the flu, and, if you do get sick, what you can do to feel better. You’ll also learn when to see your doctor and how to treat these usually minor miseries. The report also provides specific information for high-risk groups for whom the flu can be very serious.
Prepared by the editors of Harvard Health Publications in consultation with Jeffrey A. Linder, M.D., M.P.H., Associate Physician, Division of General Medicine and Primary Care, Brigham and Women’s Hospital and Assistant Professor of Medicine, Harvard Medical School. 31 pages. (2013)
About Harvard Medical School Guides
Harvard Medical School Guides delivers compact, practical information on important health concerns. These publications are smaller in scope than our Special Health Reports, but they are written in the same clear, easy-to-understand language, and they provide the authoritative health advice you expect from Harvard Health Publications.
What causes a cold and the flu?
A cold and the flu are both caused by viruses, tiny infectious agents that can survive only by getting inside the cells of animals or humans. One of the differences between a cold and the flu is the kind of virus that causes each. The flu, medically known as influenza, is always caused by one of the influenza viruses. Colds (also known as viral rhinitis, nasopharyngitis, or nonspecific upper respiratory infections), on the other hand, can be caused by more than 200 different viruses — and that estimate includes only the viruses doctors know about. The viruses that cause as many as 50% of colds in adults have not even been identified. The biggest offender, called the rhinovirus, causes up to 40% of colds and has about 100 distinct types. Other prevalent upper respiratory viruses include coronaviruses, adenovirus, and the respiratory syncytial virus. Your body reacts very differently to being infected by a cold virus versus an influenza virus. The type of virus determines what symptoms you get and how severe they will be.
Many cold viruses are extremely hard to grow in laboratory environments, and are therefore hard to study.
Learning more about the viruses that cause colds and the flu can help doctors figure out how to prevent and treat these illnesses. For most people, however, the most important thing to know is that viruses are to blame for both colds and the flu. This fact has very important implications for treating — and preventing — these illnesses. For example, knowing that colds and the flu are caused by viruses explains why taking an antibiotic would do nothing for you. Antibiotics work only on bacterial infections, not on viral infections.