mdm
02-06-2011, 03:05 AM
What Is a Common Cold?
The common cold is a group of symptoms (http://symptoms.webmd.com/default.htm) in the upper respiratory tract caused by a large number of different viruses. Although more than 200 viruses can cause the common cold, the perpetrator is usually the rhinovirus, which is to blame for causing 10% to 40% of colds. Also, the coronaviruses cause about 20% of colds and the respiratory syncytial virus (RSV) causes 10% of colds.
The rhinovirus (or other cold virus) enters your body through your nose or mouth and is easily spread when you touch someone or touch common objects (the computer keyboard or mouse, the telephone receiver, a doorknob, or eating utensils). If you aren't cautious about hand washing, you can spread the common cold to family, friends, co-workers, and people you've never met at a restaurant or the supermarket.
What Causes a Common Cold?
While getting chilled or wet is not a cause of common colds, there are factors that make you more susceptible to catching a cold virus. For example, you are more likely to catch a common cold if you are excessively fatigued, have emotional distress, or have allergies (http://www.webmd.com/allergies/default.htm) with nose and throat symptoms.
How a Common Cold Starts
With a common cold, you catch the virus from another person who is infected with the virus. This usually happens by touching a surface contaminated with cold germs and then touching your nose or mouth. You can also catch a cold by encountering secretions someone has sneezed into the air.
A cold begins when a cold virus attaches to the lining of your nose or throat. Your immune system sends white blood cells out to attack this germ. Unless you've encountered that exact strain of the virus before, the initial attack fails and your body sends in reinforcements. Your nose and throat get inflamed and produce a lot of mucus. With so much of your body's energy directed at fighting the cold virus, you're left feeling tired and miserable.
Although the common cold is usually mild, it is a leading cause of doctor visits and missed days from school and work. According to the CDC, 22 million school days are lost annually in the U.S. because of the common cold. Some estimates state that Americans suffer 1 billion colds annually.
Common Cold Symptoms:
With the common cold, you may have cold symptoms such as an itching or sore throat with sneezing, nasal congestion, watery eyes, and mucus drainage. More severe symptoms, such as high fever or muscle aches, may indicate you may have the flu and not a cold.
Kids and Common Colds
Children have about five to seven colds per year. A key reason why colds are so common in children is because kids spend time at school or in day care centers where they are in close contact with other kids most of the day. Another reason is kids have not developed as strong an immune system against colds. In families with children in school, the number of colds per child can be as high as 12 annually. Adults average about 2 or 3 colds a year, although the range varies widely. Women, especially those 20 to 30 years old, have more colds than men, possibly because of their closer contact with children. On average, people older than 60 have less than one cold a year .
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Preparing for Cold Season:
In the United States, most colds occur during the fall and winter. Beginning in late August or early September, the rate of colds increases slowly for a few weeks and remains high until March or April, when it declines. The seasonal variation may relate to the opening of schools and to cold weather, which prompt people to spend more time indoors and increase the chances that viruses will spread .
Seasonal changes in relative humidity also may affect the prevalence of colds. The most common cold-causing viruses survive better when humidity is low -- the colder months of the year. Cold weather also may make the inside lining of your nose drier and more vulnerable to viral infection .
When to Call the Doctor About a Cold
Remember, common colds are viral, not bacterial. Yet many people still ask their doctors for antibiotics when they experience common cold misery. Antibiotics kill bacteria, not viruses. Antibiotics cannot help a viral infection like a cold .
While most colds last about seven to 10 days, if your symptoms continue, you may need to call the doctor. Sometimes common colds can lead to bacterial infections in your lungs, sinuses, or ears that require medical treatment such as antibiotics
The common cold is a group of symptoms (http://symptoms.webmd.com/default.htm) in the upper respiratory tract caused by a large number of different viruses. Although more than 200 viruses can cause the common cold, the perpetrator is usually the rhinovirus, which is to blame for causing 10% to 40% of colds. Also, the coronaviruses cause about 20% of colds and the respiratory syncytial virus (RSV) causes 10% of colds.
The rhinovirus (or other cold virus) enters your body through your nose or mouth and is easily spread when you touch someone or touch common objects (the computer keyboard or mouse, the telephone receiver, a doorknob, or eating utensils). If you aren't cautious about hand washing, you can spread the common cold to family, friends, co-workers, and people you've never met at a restaurant or the supermarket.
What Causes a Common Cold?
While getting chilled or wet is not a cause of common colds, there are factors that make you more susceptible to catching a cold virus. For example, you are more likely to catch a common cold if you are excessively fatigued, have emotional distress, or have allergies (http://www.webmd.com/allergies/default.htm) with nose and throat symptoms.
How a Common Cold Starts
With a common cold, you catch the virus from another person who is infected with the virus. This usually happens by touching a surface contaminated with cold germs and then touching your nose or mouth. You can also catch a cold by encountering secretions someone has sneezed into the air.
A cold begins when a cold virus attaches to the lining of your nose or throat. Your immune system sends white blood cells out to attack this germ. Unless you've encountered that exact strain of the virus before, the initial attack fails and your body sends in reinforcements. Your nose and throat get inflamed and produce a lot of mucus. With so much of your body's energy directed at fighting the cold virus, you're left feeling tired and miserable.
Although the common cold is usually mild, it is a leading cause of doctor visits and missed days from school and work. According to the CDC, 22 million school days are lost annually in the U.S. because of the common cold. Some estimates state that Americans suffer 1 billion colds annually.
Common Cold Symptoms:
With the common cold, you may have cold symptoms such as an itching or sore throat with sneezing, nasal congestion, watery eyes, and mucus drainage. More severe symptoms, such as high fever or muscle aches, may indicate you may have the flu and not a cold.
Kids and Common Colds
Children have about five to seven colds per year. A key reason why colds are so common in children is because kids spend time at school or in day care centers where they are in close contact with other kids most of the day. Another reason is kids have not developed as strong an immune system against colds. In families with children in school, the number of colds per child can be as high as 12 annually. Adults average about 2 or 3 colds a year, although the range varies widely. Women, especially those 20 to 30 years old, have more colds than men, possibly because of their closer contact with children. On average, people older than 60 have less than one cold a year .
.
Preparing for Cold Season:
In the United States, most colds occur during the fall and winter. Beginning in late August or early September, the rate of colds increases slowly for a few weeks and remains high until March or April, when it declines. The seasonal variation may relate to the opening of schools and to cold weather, which prompt people to spend more time indoors and increase the chances that viruses will spread .
Seasonal changes in relative humidity also may affect the prevalence of colds. The most common cold-causing viruses survive better when humidity is low -- the colder months of the year. Cold weather also may make the inside lining of your nose drier and more vulnerable to viral infection .
When to Call the Doctor About a Cold
Remember, common colds are viral, not bacterial. Yet many people still ask their doctors for antibiotics when they experience common cold misery. Antibiotics kill bacteria, not viruses. Antibiotics cannot help a viral infection like a cold .
While most colds last about seven to 10 days, if your symptoms continue, you may need to call the doctor. Sometimes common colds can lead to bacterial infections in your lungs, sinuses, or ears that require medical treatment such as antibiotics