AIDS
AIDS
is the byname of acquired immunodeficiency syndrome. It is a fatal
transmissible disease of the immune system caused by the human immunodeficiency
virus (HIV). HIV slowly attacks and destroys the immune system, the body’s
defense against infection, leaving an individual vulnerable to a variety of
other infections and certain malignancies that eventually cause death. AIDS is
the final stage of HIV infection, during which time fatal infections and
cancers arise.
AIDS
was first reported in 1981 by investigators in New York and California.
Initially most cases of AIDS in the United States were diagnosed in homosexual
men, who contracted the virus primarily through sexual contact and in
intravenous drug users, who needles. In 1983 French and American researchers
isolated the causative agent, HIV, and by 1985 serological tests to detect the
virus had been developed. HIV/AIDS spread to epidemic proportions in the 1980s,
particularly in Africa, where the disease may have originated. Spread was
likely urbanization and long-distance travel in Africa, international travel,
changing sexual mores, and intravenous drug use. By 2002 AIDS had claimed over
25 million lives worldwide. Approximately 40 million people throughout the
world are infected with HIV. People living in sub-Saharan Africa account for
more than 70 percent of all infections, and in some countries of the region the
prevalence of HIV infection of inhabitants exceeds 10 percent of the
population. Rates of infection are lower in other parts of the world, but the
epidemic is spreading rapidly in Eastern Europe, India, South and Southeast
Asia, Latin American and the Caribbean. In China the government estimated that
up to 850000 people had contracted HIV by 2000 –more than half of them having
acquired the virus since 1997. In the United States the incidence of HIV/AIDS
has stabilized at about 40,000 new infections per year. One-third of all new
cases are women, for whom the primary risk factor is heterosexual intercourse.
HIV
is transmitted by the direct transfer of bodily fluids, such as blood and blood
products, semen and other genital secretions, or breast milk, form an infected
person to an uninfected person. The primary means of transmission worldwide is
heterosexual intercourse with an infected individual; the virus can enter the
body through tee lining of the vagina, penis, rectum, or mouth, HIV Frequently
is spread among intravenous drug users who share needles or syringes. Prior to
the development of screening procedures and heat-treating techniques that
destroy HIV in blood products, transmission also occurred through contaminated
blood products; many people with hemophilia contracted HIV in this way.
The
Course of HIV infection involves three stages:
a.
Primary HIV infection
b.
The asymptomatic phase, and
c.
AIDS.
During
the first stage the transmitted HIV replicates rapidly, and some persons may
experience an acute flu-like illness that usually persists for one to two
weeks. During this time a variety of symptoms may occur, such as fever,
enlarged lymph nodes, sore throat, muscle and joint pain, rash, and malaise.
The second phase of HIV infection, the asymptomatic period, lasts an average of
10 years. During this period the virus continues to replicate and there is a
slow decrease in the CD4 count. When the CD4 count falls to about 200 cells per
micro liter of blood (in an uninfected adult it is typically about 1000 cells
per micro liter), patients begin to experience the symptoms of defective immune
system. This is AIDS, the final stage of HIV infection.
Tests
for the disease check for antibodies to HIV, which appear from four weeks to
six months after exposure. The most common test for HIV is the enzyme-linked
immunosorbent assay (ELISA). If the result is positive, the test is repeated on
the same blood sample. Another positive result is confirmed using a more
specific which screen for viral RNA and therefore allow detection of the virus
after very recent exposure, and Single Use Diagnostic Screening (SUDS) are
other options. Because these tests are very expensive, they are often out of
reach for the majority of the population at risk for the disease.
There
is no cure or effective vaccine for HIV infection. Efforts at prevention have
focused primarily on changes in sexual behavior such as the practice of
abstinence and the use of condoms. Attempts to reduce intravenous drug use and
to discourage the sharing of needles have also led to a reduction in infection
rates in some areas.
AIDs
infection is treated with three classes of antiretroviral medications. Protease
inhibitors, nucleoside reverse transcriptase (RT) inhibitors and non-nucleoside
RT inhibitors. Because HIV rapidly becomes resistant to any single
antiretroviral drug, combination treatment is necessary for effective
suppression of the virus. Highly active antiretroviral therapy (HAART), a
combination of three or more RT and protease inhibitors, has resulted n a
marked drop in the mortality rate from HIV infection in the United States and
other industrialized states since its introduction in 1996. Because of its high
cost, HAART is generally not available in regions of the world hit hardest by
the AIDS epidemic.
Though
AIDS is a serious disease, it is not transmitted by things like handshaking,
embracing, using the same latrine, swimming-pool, or pond, or sitting in the
same chair. This is a matter of great regret that in many societies AIDS
victims do not get social help and compassion. People boycott them completely.
It is necessary to be kind and helpful to the AIDS victims.
