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(Acquired Immunodeficiency Syndrome)

The lack of a proper immune system is the main reason behind the development of this condition. It is acquired during the lifetime of a person signifying that it is not a congenital disease. The meaning of ‘Syndrome’ is ‘group of symptoms.’

Note: First time AIDS was reported in 1981, and since then it has been increasing and spreading all around the world killing millions of people.

AIDS is caused by HIV (Human Immunodeficiency Virus), which is a retrovirus. These viruses have an envelope enclosing the RNA genome.

Transmission of HIV infection usually occurs by:

  • Sexual Contact with an infected person
  • Contaminated blood transfusion and blood products.
  • Sharing infected needles such as in the case of intravenous drug abusers
  • From infected mother to her child through the placenta

Risk of infection increases in people involved with:

  • Multiple sexual partners
  • Drug addicts (who take drugs intravenously)
  • Individuals taking repeated blood transfusions
  • Children born to an HIV infected mother

It is important to know that HIV or AIDS does not spread by touch or physical contact. It spreads only through body fluids. Hence, there is no need to isolate HIV/AIDS infected persons from family and society. A person infected with HIV may show symptoms only after a few months to many years (around 5-10 years).

How Virus enter and affect our body?

  • The virus enters the body and enters into macrophages where the RNA genome of the virus starts replicating and form viral DNA with the help of reverse transcriptase enzyme.
  • This viral incorporated DNA enters the host cell’s DNA and starts the production of virus particles in infected cells.
  • The virus present in macrophages continue to produce more virus and in this way act like a virus making factory.
  • Simultaneously, the virus enters the T_lymphocytes and produce progenies. The progeny viruses that are released in the blood further attack other helper T-lymphocytes.
  • This attack is repeated several times leading to a reduction in the number of T-lymphocytes in the body of the infected person.
  • In this period, the person suffers from bouts of diarrhoea, fever and weight loss.
  • Further, reduction in T-lymphocytes leads to reduced immune system response and person get prone to even the most simple infections that can be otherwise be easily overcome by the natural immune response of the body. Infections can be from other viruses, Mycobacterium, bacterias, and even fungi.

AIDS treatment

Although there is no cure for this disease. However, after diagnosis with the help of ELISA (enzyme-linked immunosorbent assay), the treatment with antiretroviral drugs is initiated. It is not completely effective but still can extend the life of the infected person to some extent. Death is inevitable when a person is suffering from AIDS.

Prevention of AIDS

Prevention is the best policy in AIDS as it has no cure once the virus enters the body. Also, the infection spreads due to conscious behaviour patterns and is not something that happens accidentally.

  • Infection due to blood transfusion or from mother takes when there is poor monitoring. It mostly results due to ignorance when people are not aware of the consequences of unsafe practices.
  • HIV Prevention England (HPE) – National HIV prevention programme for England.
  • WHO has also started a lot of programmes to prevent HIV infection from spreading. Some of the actions taken by it are ensuring –
    • Safe blood from blood banks
    • Use of only disposable needles and syringes in private and public hospitals and clinics
    • Free distribution of condoms.
    • Advocating safe sex
    • Regular check-ups in HIV prone populations
  • To prevent infection, it is important that when a person comes to knowledge about his infection, it is immediately reported and treatment is started so that others are not infected.
  • People in general needs to show sympathy towards HIV infected persons that can remove the shame and social stigma so that an infected person can come out and get early treatment.
  • Society and medicine will have to go hand in hand to prevent the spread of AIDS.