The
human body has several lines of defense against infection, which work to
prevent germs from invading the body or to destroy them once they find their
way in.
from their mothers, both during
pregnancy (across the mother's placenta ) and
after birth from breast milk. These
antibodies usually disappear within 6 to 12 months, but until then they help
protect the infant against a range of infections, including pneumonia ,
bronchitis ,
influenza ,
and ear infection. Doctors also can give people gamma
globulin, an antibody preparation that offers temporary immunity to patients
who might need this protection.
When a person gets an immunization, or
vaccine , the body's immune system learns to
recognize that particular bacteria or virus. If, sometime later, the person is
exposed to the germ again, the body can fight it off and not come down with the
disease.
A person may develop immunity in the
following ways:
1.
Immunity through diseases:
When
a person develops certain disease due to the entry of a pathogen for the first
time, then the pathogen multiplies in his body at a faster rate and gradually
spread to the different parts. Then the antibody formation starts
slowly and by that time the person suffers from the disease. But as the rate of
antibody production increases, the person gets cured gradually. This is because of the fact that
the antibody formed in response to the foreign antigen, neutralizes the action
of the latter. But
the same person does not suffer from the disease due to subsequent infection by
the same pathogen.
For
example, If a person suffers from measles due to
the entrance of measles virus into the body, then corresponding antibody
production will start in order to neutralize the action of the virus. After some days the person gets
cured, but the antibody remains in his blood for long time. When the virus
enters into the body again, because of the presence of the antibody the person
does not suffer from the disease again.
2.
Vaccination:
It
is the process of producing immunity to a disease by the vaccine. In this process the
weaken or dead pathogens are injected into the body, so that immunity develops against
the pathogen in him but the disease is not caused. Vaccination can be injected
or can be given orally.
Other
Defenses
Along with physical barriers and
the immune system, the body has several other mechanisms that fight antigens. Coughing
or sneezing is an automatic reflex that can rid the body of irritants. Interferon
(in-ter-FEER-on), a naturally occurring substance in the body that fights
infection or tumors, is produced automatically when the immune system is called
into action.
The inflammatory response, or
inflammation (is
an important body response to injury. When bacteria, toxins, burns, or other
culprits damage tissue, the injured tissues leak chemicals, including histamine and other substances. This chemical
cocktail causes blood vessels around the damaged area to leak fluid into the
injured tissues and make them swell. The increased flow of blood and fluid to
the area also brings phagocytes and other infection-fighting cells to take care
of any toxins or other antigens in the area. Pus, which is a fluid containing
dead body cells and tissue, dead bacteria, dead toxins, and dead and living
phagocytes, sometimes forms at the site of inflammation.
To the eye, inflamed
skin may appear red and swollen, and the area may feel slightly warm to the
touch. Ancient physicians used the Latin terms
"dolor," "rubor," "calor," and "tumor"
to refer, respectively, to pain, redness, heat, and swelling, the hallmarks of
inflammation.
Inflammation also may cause a fever. The increase in body heat can help kill
bacteria or viruses at the site of the infection.
Sumber : Bpk. Dr. Iskandar Zulkarnain
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ahmad baihaqi
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