Medical Animation: HIV and AIDS


HIV is the Human
Immunodeficiency Virus. If you have HIV, you
have an infection that damages your immune system
over time, and causes AIDS. AIDS stands for Acquired
Immunodeficiency Syndrome. It is the final stage of
an HIV infection, when your immune system is
damaged and too weak to fight off
ordinary infections. When foreign invaders, such
as bacteria and viruses, get into your body, they
can cause infections. These events activate
your body’s defenses. The white blood cells
of your immune system are part of your
body’s defenses. One type of white
blood cell, called helper T lymphocytes,
or helper T cells, strengthen your immune
system’s response to infection in two ways. First, helper T cells
release chemicals that attract other
white blood cells to the site of the infection. These additional
white blood cells attack the invading bacteria
or virus, as well as other infected cells. Second, helper T cells
release chemicals that cause other white
blood cells to multiply. These new white blood
cells create markers, called antibodies,
which can identify the same foreign invader
throughout your body. Antibodies attach to
the bacteria or virus, marking them as targets for your
immune system to destroy them. If you have HIV, it
travels through your blood and other body fluids to infect
and kill certain white blood cells. The virus enters helper T cells,
which are the primary target. Once inside, the virus
makes many copies of itself. As these virus
particles are made, they leave the damaged helper
T cell to infect other cells. The T cell loses its
ability to protect the body from the ongoing
infection and dies. In this way, HIV
spreads and kills more of your helper T cells,
weakening your immune system. As a result, other
types of infections are able to take advantage
of your body’s inability to defend itself. These infections are called
opportunistic infections. If you have an HIV
infection, and one or more opportunistic infections,
you have AIDS. Some of the common AIDS-related
opportunistic infections are inflammation of the tissues
covering your brain and spinal cord, called meningitis,
inflammation of your brain, called encephalitis. Respiratory illnesses, such
as pneumonia and tuberculosis. Intestinal illnesses,
such as chronic diarrhea caused by infectious parasites. And cancers, such
as Kaposi’s sarcoma and non-Hodgkin lymphoma. HIV passes from person to person
through infected body fluids. HIV can enter your body during
unprotected sex, while sharing drug injection needles,
during your own childbirth, while breastfeeding
from your mother, or from contaminated
blood or blood products. Although there is
no cure for HIV, drugs called
antiretroviral medications can reduce the amount
of HIV in your body. One class of
antiretroviral medication, called entry or
fusion inhibitors, disrupts the HIV
infection process by preventing the virus from
attaching to your cells. Other classes of
antiretroviral medications include reverse
transcriptase inhibitors, protease inhibitors, and
integrase inhibitors. These drugs prevent the
creation, assembly, and spread of new viruses. Your doctor may prescribe
a combination of these drug classes, known as highly
active antiretroviral therapy, or HAART. Antiretroviral medication
doesn’t completely remove HIV from your body,
but slows it down enough to enable your immune
system to fight infections. Regular blood tests
will let your doctor know how effective your
antiretroviral medication is in controlling HIV. If the number of helper T cells
is high enough in your blood sample, your
medication is working. Treatments for the
opportunistic infections of AIDS are medications specific
for each type of infection. For example, your doctor
may prescribe antibiotics if you have pneumonia
or tuberculosis. To avoid getting or
spreading an HIV infection, know your HIV status and
your partner’s status by getting tested regularly. The most effective way
to prevent HIV infection is to avoid vaginal
and anal sex. When engaging in
sexual activity, you will be less
likely to contract HIV if you only have sex with
one uninfected partner, or use latex condoms
for protection. Avoid using injectable illegal
drugs, or sharing drug needles, because the needles may
have the virus on them. Avoid intoxication
from drugs or alcohol, because you will be
more likely to engage in unsafe sexual behavior.