There isn't a single illness that can be identified as a cold. A
cold may cause sneezing, nasal congestion, headaches, sore
throats and other symptoms, but there are over 200 different
viruses that can cause these symptoms.
Nearly everyone has had
a cold as it is such a common ailment, in fact, that doctors
refer to it as the "common cold." In 1998 alone,
more than 65 million people in America reported having colds
and nearly half (29.8 million) were children under the age of
17. Since many people don't go to the doctor when they have
colds, the actual number is probably much higher.
A cold usually goes away in about a week, but the symptoms,
which can include sneezing, nasal congestion, headaches,
slight fever, sore throat and others, are unpleasant enough to
make a person feel uncomfortable. Over-the-counter cold
medicines can help relieve these symptoms. If cold symptoms
last for more than two weeks, it is a good idea to check with
a doctor to determine whether another illness, such as a sinus
infection, is present.
A Closer Look at Colds
is a picture of a cold virus. Though there are over 200 of
them, they all pretty much look the same. After you catch one of the viruses, your body builds
up immunity to it, and you are less likely to catch that cold
again. That's is one reason why adults generally have fewer colds than
children do. Adults are immune to more of the cold viruses.
and flu viruses enter the nose, mouth and eyes through
droplets in the air and through contact with the things we
touch. Cold symptoms appear 18 to 48 hours after exposure to a
virus. Flu attacks stronger and faster than colds, and usually
strikes between December and March. Though colds and flu share
many of the same symptoms, colds are less severe, do not last
as long, and do not include the high fever of flu.
vessels in and around the nose dilate (or get bigger) in response to the
virus. This speeds up the arrival of germ-fighting cells and
causes the mucous membrane to swell. The body also releases
extra histamine, a chemical that causes blood vessels to
dilate even more.
body's fight against the virus results in irritation, swelling
and increased mucus production. The mucus flushes the viruses
down the throat. Both the virus and the germ-fighting cells in
the mucus can irritate the throat, causing the soreness and
coughing you might experience with a cold.
swelling in the nose can block air passages and sinus
openings, which causes congestion and could lead to bacterial
infections of the sinuses.
same process can happen in the ear. Swelling around the
opening in the eustachian tube (which connects the middle ear
with the throat) traps bacteria and fluid in the middle ear.
This can result in an infection and the earaches that many
body's virus-fighting efforts put a strain on your whole body.
That's what triggers the aches, pains, fatigue and fever that
often accompany a cold.