Every one of us has an immune system which protects our body from foreign invaders like bacteria and virus. The immune system keeps those invaders out or seeks out and destroys them. The condition, we are going to discuss is HIV which attacks immune system of our body. Actually, It stands for human immunodeficiency virus. It weakens a person’s immune system by destroying CD4 cells that fight against foreign agents. The disease if left untreated, it reduces the number of CD4 cells and can lead to most advanced stage named AIDS (acquired immunodeficiency syndrome) defined by the occurrence of any of more than twenty opportunistic infections or related cancers. In other words, acquired immune deficiency syndrome is a chronic illness caused by a retrovirus known as Human Immunodeficiency Virus. This causes progressive deterioration of body’s immune system leading to increased susceptibility to infection and tumours. Therefore, HIV and AIDS are not same, the acquired AIDS occurs when HIV has significantly harmed our body’s immune system. Having HIV does not mean having AIDS. In most of the cases, AIDS occurs 8-10 years after initial HIV infection.
Magnitude of HIV/AIDS
HIV/AIDS is not just a health problem, but also a social problem worldwide. According to World Health Organization (WHO) statistics, there were approximately 36.7 million people living with AIDS at the end of 2015 around the globe. Furthermore, an estimated 36.7 million people were living with HIV in 2015 globally, and 1.8 million of these were children. An estimated 2.1 million people were newly infected with HIV in 2015. An estimated 35 million people have died from this diseases-related causes so far, including 1.1 million in 2015. It remains one of the world’s most significant public health challenges, particularly in low- and middle-income countries.
- Homosexual or bisexual men (50% of cases )
- Intravenous drug abusers
- Recipients of blood and blood components
- Heterosexual contacts of members of high-risk groups (eg. intravenous drug abusers)
Routes of transmission
Source of infection: Greatest concentration of the virus is in blood, semen and cerebrospinal fluid while lower concentration is in tears, saliva, breast milk, and urine, cervical and vaginal secretions.
HIV can transmit through unsafe sexual intercourse (anal or vaginal) or oral sex with an infected person; transfusions of contaminated blood or blood products or transplantation of contaminated tissue; the sharing of contaminated injecting equipment and solutions (needles, syringes) or tattooing equipments; through the use of contaminated surgical equipment and other sharp instruments; the transmission between a mother and her baby during pregnancy, childbirth and breastfeeding.
The virus does not survive long outside the human body (such as on surfaces) and it cannot reproduce outside a human host. Therefore, it does not spread by:
- Air or water
- Mosquitoes, ticks or other insects
- Shaking hands, hugging, sharing toilets, sharing dishes/drinking glasses, kissing with someone who is HIV-positive
- Other sexual activities that don’t involve the exchange of body fluids (for instance, touching)
Sign and symptoms
The first HIV symptoms may include swollen glands in the throat, groin or armpit. Other early HIV symptoms include slight fever, headaches, fatigue, and muscle aches. As the disease progresses, other symptoms start appearing. The common symptoms include diarrhea for more than a week, dry cough, memory loss, depression and neurological disorders, profound, unexplained fatigue, rapid weight loss, pneumonia, recurring fever or profuse night sweats, enlargement of lymph nodes, white spots on tongue, in mouth, or throat, increasing shortness of breath, unexplained bleeding from growths on the skin, from the mouth, nose, anus, or vagina, or from an opening in the body etc.
There are two major targets of HIV infection viz immune system and central nervous system. The clinical manifestations are categorized into three categories.
Category A: It is characterized by no symptoms or symptoms of primary HIV infection that includes mild illness like fever, sore throat and Rash, Most infected people have no symptoms for first 5 years or so, Antibodies (protein produced primarily by plasma cells which are used by the immune system to neutralize pathogens) take 2-12 weeks to appear in blood. This time is also known as window period.
Category B: This phase is characterized by symptoms of immune deficiency not serious enough to be called AIDS.
Category C: In this category, a person has an AIDS-defining illness like opportunistic infections, tuberculosis, Kaposi Sarcoma, Candida esophagitis, Cryptococcus meningitis, Pneumocystis carinii pneumonia (PCP), AIDS encephalopathy etc.
- Screening tests: First test with high Sensitivity (ELISA), Second test with high Specificity (Western Blot)
- Virus Isolation
- CD4 Count: Prognostic implications
Prevention and Control
Prevention is of great importance in HIV/AIDS as there is no cure for the disease. Emphasis should be given to avoiding unsafe sex, using condoms, avoiding shared razors/toothbrush, IV needles and syringes. Timely and accurate information should be provided to people as per the need. Similarly, a high-risk group should not donate blood and organs. Blood should be screened and strict sterilization practice should be followed.
Access to HIV testing and medicines should be dramatically accelerated. World Health Organization is recommending innovative HIV-self-testing and partner notification approaches to uplift HIV testing services among undiagnosed people.
If the reproduction of HIV stops, then the body’s immune cells are able to live longer and provide the body with protection from infections. Anti Retroviral Therapy (ART) are medications that treat HIV. The drugs do not kill or cure the virus. Yet, when taken in combination they can prevent the growth of the virus. Effective ART results in a reduction in viral load, the amount of virus in the body, greatly reducing the risk of transmitting the virus sexual partners. If the HIV positive partner in a couple is on effective ART, the possibility of sexual transmission to the HIV-negative partner can be reduced by as much as 96%. Expanding coverage of HIV treatment contributes to HIV prevention efforts.