HIV is a virus which is most commonly passed on by sexual contact. HIV attacks cells of the immune system. Untreated, the immune system weakens so that the body cannot defend against various bacteria, viruses and other germs.What are HIV and AIDS?
HIV stands for human immunodeficiency virus. HIV destroys cells in the body called CD4 T cells. CD4 T cells are a type of lymphocyte (a white blood cell). These are important cells involved in protecting the body against various bacteria, viruses and other germs.
AIDS stands for acquired immunodeficiency syndrome. This basically describes the range of infections and illnesses which can result from a weakened immune system caused by HIV.
HIV and AIDS is not the same thing and all HIV infections do not progress to develop AIDS. AIDS is unlikely to develop in people who have been treated in the early stages of HIV infection. Even in people who do not receive treatment, there is usually a time lag of several years between first being infected with HIV and then developing infections and other AIDS-related problems.How do you become infected with HIV?
- Sexual transmission. This is the most common way to pass the virus on. Having vaginal or anal sex with an infected person is the most common route. Oral sex carries a much lower risk but this can increase if you have such as ulcers, bleeding or damaged gums or a sore throat. You cannot be infected with HIV by coming into contact with the saliva of an infected person (for example, through kissing or coming into contact with spit). HIV is not passed on by coughing or sneezing.
- Needle sharing. HIV (other viruses such as hepatitis B and hepatitis C) can be passed on by people who are use injectable drugs and share needles, syringes and other injecting equipment which is contaminated with infected blood.
- Infected blood. Blood donations obtained from poorly equipped labs that do not adhere to the stringent standards necessary is a common way of transmitting the infection in developing countries like India.
- Accidental needle stick injuries. This usually occurs in a healthcare setting.
- From mother to child. HIV can be passed to an unborn child from an HIV-positive mother. However, with appropriate treatment the risk of transmission of HIV from mother to baby can be reduced to less than 1 in 100. HIV can occasionally be passed to babies through breast milk during breast-feeding. If formula milk is available, mothers with HIV are encouraged not to breast-feed.
Once HIV is in your body the virus attaches to and gets into the CD4 T cells. The virus then uses the DNA (the genetic code inside the cell) to make copies of itself. As new virus particles break out of a CD4 T cell, the cell dies. The new virus particles then attach and enter new CD4 T cells and so the process continues. Millions of new virus particles are made in CD4 T cells each day and millions of CD4 T cells die each day.
Once the level of CD4 T cells goes below a certain level, your immune system is weakened. If your immune system is severely weakened by HIV infection then you are likely to develop various opportunistic infections. A low level of CD4 T cells also increases the risk of developing other conditions which the immune system helps to prevent such as certain cancers.What are the symptoms of HIV and AIDS?
- Primary infection with HIV
When you first become infected with HIV it is known as the primary infection. The three most common symptoms are sore throat, fever and a blotchy red rash. Other symptoms can include feeling sick, diarrhea, swollen glands, headache, tiredness and general aches and pains. Most of these symptoms resemble a mild viral infection or common cold.After the primary infection
After any primary infection settles, you can remain without any symptoms for several years. However, the virus continues to multiply, the number of CD4 T cells tends to gradually fall and you can pass on the virus to others. In time you may start to develop problems such as recurring mouth ulcers, recurring herpes or shingles infections, or seborrhoeic dermatitis (a skin condition caused by a yeast). Old tuberculosis (TB) infection may reactivate in some cases.Symptoms of AIDS
Typically, a person with AIDS has:
- A very low level of CD4 T cells (around 200 cells per cubic millimetre of blood or below), and/or
- One or more opportunistic infections.
- Certain cancers. Kaposi's sarcoma is a cancer which is usually only seen in people with AIDS.
- An AIDS-related brain illness such as HIV encephalopathy .
- A severe weight loss syndrome.
Most healthcare facilities offer a rapid blood test(tri-dot test) for HIV and can give results within thirty minutes.Assessing the extent of disease
If you are confirmed to have HIV then your doctor may do a blood test to check the amount of virus in your blood (the viral load) and the number of CD4 T cells in your blood. These tests may be done from time to time to assess how far the disease has progressed and the response to treatment.Treatment for HIV infection?
Although there is still no cure for HIV, treatment is now effective at allowing people with HIV to live their lives as normally as possible. Since the introduction of medicines to treat HIV, the death rates from AIDS have reduced dramatically.Treatment to tackle the virus itself
HIV is now a treatable medical condition and most people with the virus remain fit and well on treatment.
Antiretroviral medicines work against HIV infection by slowing down the replication of the virus in the body.
The newer drugs are stupendously effective at halting the progression of disease and even achieve partial reversal. There are several classes of these medicines which include: nucleoside reverse transcriptase inhibitors (NRTIs), nucleotide reverse transcriptase inhibitors (NtRTIs), protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs).
A still newer classes of medicines have recently been introduced which are integrase inhibitors, fusion inhibitors and CCR5 antagonists.
In contrast to the previous Anti Retroviral Therapy (ART), this is referred to as highly active antiretroviral therapy or HAART.
Taking three or more antiretroviral medicines at the same time, each attacking HIV at different points in its cycle of replication is more effective than one or two medicines alone.
The aim of treatment is to reduce the viral load to low levels. In most people who are treated with ART, the viral load reduces to very low levels and the number of CD4 T cells rises. This means your immune system is no longer as weakened and. However, it is vital to take the medication regularly and exactly as prescribed to maintain success, and to help to prevent the virus from becoming resistant to the medicines.When to start treatment with antiretroviral medicines?
- Your CD4 T cells fall below a certain level (around 350 cells per cubic millimeter of blood or less) - even without symptoms.
- Opportunistic infections or other AIDS-related problems develop.
- Wearing a condom when having sex is very important to protect against other sexually transmitted infections, including herpes and hepatitis.
- People with HIV are usually vaccinated against hepatitis A and hepatitis B, influenza and the pneumococcus.
- Opportunistic infections are usually treated with antibiotics, antifungals or anti-TB medicines, obviously depending on which infection develops.
There is no vaccine to prevent HIV. Development of one is proving to be very difficult, as the HIV virus is constantly mutating and changing. Therefore, the main way to prevent infection by HIV is to avoid activities that put you at risk, such as sharing needles and having sex without a condom.What is the prognosis (outlook)?
People with HIV who are diagnosed in good time can expect to lead a near-normal lifespan. A study to predict the life-expectancy of men infected with HIV at 30 years of age in 2010 found that they could expect to live to 75, based on access to current treatments.
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