AIDS (Acquired Immuno Deficiency
Syndrome) was first reported in the United States in 1981
and has since become a major worldwide epidemic. AIDS is caused
by HIV (human immunodeficiency virus). By killing or damaging
cells of the body's immune system, HIV progressively destroys
the body's ability to fight infections and certain cancers.
People diagnosed with AIDS may get life-threatening diseases
called opportunistic infections, which are caused by microbes
such as viruses or bacteria that usually do not make healthy
people sick.
More than 900,000 cases of AIDS have been reported in the
United States since 1981. As many as 950,000 Americans may
be infected with HIV, one-quarter of whom are unaware of their
infection. The epidemic is growing most rapidly among minority
populations and is a leading killer of African-American males
ages 25 to 44. According to the Centers for Disease Control
and Prevention (CDC), AIDS affects nearly seven times more
African Americans and three times more Hispanics than whites.
In recent years, an increasing number of African-American
women and children are being affected by HIV/AIDS. In 2003,
two-thirds of U.S. AIDS cases in both women and children were
among African-Americans.
TRANSMISSION
HIV is spread most commonly by having unprotected sex with
an infected partner. The virus can enter the body through
the lining of the vagina, vulva, penis, rectum, or mouth during
sex.
Risky Behavior
HIV
can infect anyone who practices risky behaviors such as
- Sharing
drug needles or syringes
-Having sexual contact, including oral, with an infected person
without using a condom
-Having sexual contact with someone whose HIV status is unknown
-Infected blood
HIV
also is spread through contact with infected blood. Before
donated blood was screened for evidence of HIV infection and
before heat-treating techniques to destroy HIV in blood products
were introduced, HIV was transmitted through transfusions
of contaminated blood or blood components. Today, because
of blood screening and heat treatment, the risk of getting
HIV from such transfusions is extremely small.
Contaminated
needles
HIV
is frequently spread among injection drug users by the sharing
of needles or syringes contaminated with very small quantities
of blood from someone infected with the virus.
It
is rare, however, for a patient to give HIV to a health care
worker or vice-versa by accidental sticks with contaminated
needles or other medical instruments.
Mother
to child
Women
can transmit HIV to their babies during pregnancy or birth.
Approximately one-quarter to one-third of all untreated pregnant
women infected with HIV will pass the infection to their babies.
HIV also can be spread to babies through the breast milk of
mothers infected with the virus. If the mother takes certain
drugs during pregnancy, she can significantly reduce the chances
that her baby will get infected with HIV. If health care providers
treat HIV-infected pregnant women and deliver their babies
by cesarean section, the chances of the baby being infected
can be reduced to a rate of 1 percent. HIV infection of newborns
has been almost eradicated in the United States due to appropriate
treatment.
A
study sponsored by the National Institute of Allergy and Infectious
Diseases (NIAID) in Uganda found a highly effective and safe
drug for preventing transmission of HIV from an infected mother
to her newborn. Independent studies have also confirmed this
finding. This regimen is more affordable and practical than
any other examined to date. Results from the study show that
a single oral dose of the antiretroviral drug nevirapine (NVP)
given to an HIV-infected woman in labor and another to her
baby within 3 days of birth reduces the transmission rate
of HIV by half compared with a similar short course of AZT
(Azidothymidine). For more information on preventing transmission
from mother to child, go to http://aidsinfo.nih.gov/guidelines.
Saliva
Although
researchers have found HIV in the saliva of infected people,
there is no evidence that the virus is spread by contact with
saliva. Laboratory studies reveal that saliva has natural
properties that limit the power of HIV to infect, and the
amount of virus in saliva appears to be very low. Research
studies of people infected with HIV have found no evidence
that the virus is spread to others through saliva by kissing.
The lining of the mouth, however, can be infected by HIV,
and instances of HIV transmission through oral intercourse
have been reported.
Scientists
have found no evidence that HIV is spread through sweat, tears,
urine, or feces.
Casual
contact
Studies
of families of HIV-infected people have shown clearly that
HIV is not spread through casual contact such as the sharing
of food utensils, towels and bedding, swimming pools, telephones,
or toilet seats.
HIV
is not spread by biting insects such as mosquitoes or bedbugs.
Sexually
transmitted infections
If
you have a sexually transmitted infection (STI) such as syphilis,
genital herpes, chlamydial infection, gonorrhea, or bacterial
vaginosis appears, you may be more susceptible to getting
HIV infection during sex with infected partners.
EARLY
SYMPTOMS OF HIV INFECTION
If you are like many people, you will not have any symptoms
when you first become infected with HIV. You may, however,
have a flu-like illness within a month or two after exposure
to the virus. This illness may include
- Fever
-Headache
-Tiredness
-Enlarged lymph nodes (glands of the immune system easily
felt in the neck and groin)
These symptoms usually disappear within a week to a month
and are often mistaken for those of another viral infection.
During this period, people are very infectious, and HIV is
present in large quantities in genital fluids.
More
persistent or severe symptoms may not appear for 10 years
or more after HIV first enters the body in adults, or within
2 years in children born with HIV infection. This period of
"asymptomatic" infection varies greatly in each
individual. Some people may begin to have symptoms within
a few months, while others may be symptom-free for more than
10 years.
Even
during the asymptomatic period, the virus is actively multiplying,
infecting, and killing cells of the immune system. The virus
can also hide within infected cells and lay dormant. The most
obvious effect of HIV infection is a decline in the number
of CD4 positive T (CD4+) cells found in the blood-the immune
system's key infection fighters. The virus slowly disables
or destroys these cells without causing symptoms.
As
the immune system worsens, a variety of complications start
to take over. For many people, the first signs of infection
are large lymph nodes or "swollen glands" that may
be enlarged for more than 3 months. Other symptoms often experienced
months to years before the onset of AIDS include
- Lack
of energy
-Weight loss
-Frequent fevers and sweats
-Persistent or frequent yeast infections (oral or vaginal)
-Persistent skin rashes or flaky skin
-Pelvic inflammatory disease in women that does not respond
to treatment
-Short-term memory loss
Some people develop frequent and severe herpes infections
that cause mouth, genital, or anal sores, or a painful nerve
disease called shingles. Children may grow slowly or be sick
a lot.
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