American Medical Association Family Medical Guide - American Medical Association [397]
Nasal decongestants (available as tablets, sprays, or drops) shrink and dry out the swollen, mucus-producing tissue inside the nose and sinuses, making it easier to blow the mucus out of your nose. An over-the-counter cold medication called pleconaril begins to ease cold symptoms in a day and clears up a runny nose up to a day earlier than usual. Unlike other cold medications, pleconaril attacks the virus itself rather than just relieving cold symptoms.
Because antibiotics are effective only against bacteria, don’t ask your doctor to prescribe an antibiotic for a cold. Your doctor will prescribe an antibiotic only if you have symptoms of a bacterial infection such as an earache, sinusitis, shortness of breath, or a painful cough.
Influenza
Influenza, usually called the flu, is a viral infection of the respiratory tract. The flu can spread from the nose or mouth to the rest of the respiratory system, including the lungs. It is usually spread by touching an infected person or contaminated surface or by inhaling infected droplets coughed or sneezed into the air. If a bacterial infection develops in addition to the viral infection and travels from the upper respiratory tract to the lungs, it can cause more serious disorders, such as acute bronchitis (see page 655) or pneumonia (see page 660). Influenza kills about 20,000 people a year in the United States.
There are three main types of influenza virus—A, B, and C. If you have had the flu caused by a type C virus (a relatively mild type of flu with symptoms similar to those of a cold), you are immune to it for life. If you have been infected with a particular strain of a type A or B influenza virus, you have immunity to that strain only. Although both A and B influenza viruses can produce new strains that can overcome a person’s immunity, the type B virus seldom alters itself sufficiently to do so. But the type A virus constantly changes, and the changes are significant enough to make it look like a new virus to the immune system. For this reason, most flu epidemics and severe outbreaks are caused by type A viruses. These strains are usually named after their place of origin (such as the Hong Kong flu).
Influenza usually occurs in small outbreaks, often in the winter. Every few years, in unpredictable intervals, it occurs in epidemics. Two or three epidemics caused by different strains of the virus can occur at the same time. Epidemics die out when everyone who has been infected by a particular strain of a flu virus becomes immune to that strain.
Symptoms
Symptoms of the flu vary widely. You may have a fever with shaking and chills, sneezing, headache, muscle aches, and a sore throat. You may then develop a dry, hacking cough and chest pain. You will probably feel very weak. Some children have abdominal pain and seizures. If you have no complications, you should recover in 1 to 2 weeks, although you may still feel weak for a few weeks. If you seem to be the only person who has the flu, you may have some other viral illness such as mononucleosis (see page 935).
Flu Shots
Because a flu infection can be debilitating or life-threatening, most doctors recommend that even healthy young adults and children get a flu shot every year. The vaccine now also comes in a nasal spray. The flu vaccine protects you for only a year (sometimes less), even against the strain it is meant to resist. Flu shots are usually administered in late fall after scientists have determined which strains are likely to cause the most widespread infections that year. In rare cases, flu shots can cause minor flulike symptoms such as a low fever and aches for a day or two. Because the vaccine is made from eggs, people who are allergic to eggs should not get a flu shot.
Doctors especially recommend flu shots every year for the following people:
• Those over age 65
• People who have a chronic disease (such as diabetes or cancer) or any