What is HIV?
HIV stands for Human Immunodeficiency Virus. The virus enters the body- in this case, across the placenta or during childbirth- and may remain inactive (this is known as being HIV-positive). AIDS is the disease caused by the HIV virus; once the virus is active it attacks and destroys T helper cells in the immune system- these cells normally help to prevent infection. If destroyed, you will be unable to defend yourself against any pathogen that enters your body and you may contract a range of opportunistic infections. It is the effect of these diseases which eventually kill a person with HIV. AIDS stands for Acquired Immune Deficiency Syndrome.
It can also be transmitted by: exchange of bodily fluids, unprotected sex, use of unsterilised surgical equipment, sharing needles etc.
HIV/AIDS is a worldwide disease, and is still spreading in pandemic proportions. The majority of people living with it are living in sub-Saharan Africa.
Latest case
The child in question is now 2 1/2 years old, now off of medication for over a year without infection. Dr Deborah Persaud presented her findings at a conference for retroviruses and opportunistic infections, she said 'This is a proof of concept that HIV can be potentially curable in infants'.
The first person believed to be recovered from HIV, Timothy Ray Brown had his infection eradicated with leukaemia treatment and stem cell transplant from a donor with a genetic mutation that resists HIV- very rare. On the contrary, this case involved a mix of drugs (antiviral therapy) already used to treat infant HIV.
This suggests that the quick treatment meant that the virus did not have chance to form hideouts in the body. HIV specialist Dr Hannah Gay put the baby on a cocktail of 3 standard HIV fighting drugs at 30 hours old- before the lab tests came back from confirming infection (high risk of the baby to have HIV as the mother recently found out she was carrying the virus and had no treatment). The treatment continued for 18 months, then the child disappeared from the system and 5 months later it was a surprise to find the virus had not returned.
Does this mean a cure?
In the above case, there are very special circumstances: the HIV battled hard and fast just after birth. This worked, meaning that the infant can grow up without having to worry about the implications of HIV- however, the same approach could not be applied to adult cases, with people finding oiut they have the virus a long time (months, years) after acquiring HIV.
High risk groups in the UK are offered regular testing for the virus, free- however, 25% of people with HIV are unaware of it. This gap in acquiring and finding out that HIV has been acquired gives time for the virus to hide away in the immune system, so no therapy can touch it.
This approach is definitely not going to provide a cure for the majority affected by the virus. Antiretroviral therapies in the 90s had a great impact on the number of deaths- HIV is not the great killer it once was. But the hunt for a 'cure' is still on.
Opening my latest NewScientist magazine, I was immediately drawn to its covering of the HIV case. Beside stating the majority of things I could learn via the news, this went into more depth of the sceptical response and future for this kind of treatment.
Mario Stevenson said 'At present, this can best be described as a functional rather than a sterilising cure' although also says that every baby of HIV positive mothers should receive 'triple-drug treatments'.Other beliefs, of Davis Margolis, are that the baby could have been a 'super-controller'- this means that the baby had a natural resistance to the virus, due to a fault in the gene that manufactures CCR5 receptors on white blood cells. HIV needs to attach to these receptors to successfully invade cells, meaning super-controllers are protected from infection from this nasty virus. This same mutation was involved in the only other 'cure' case for HIV- Timothy Ray Brown, mentioned above; the stem cells involved in his treatment were from the bone marrow from a super-controller.
Now, therapies are being developed that focus on these CCR5 receptors. Another hope for treatment is vorinostat- a drug that can 'flush out' HIV from its hiding places in cells and ARVs (antiretroviral drugs) can then be used to keep the virus at bay. Several countries are now giving ARVs to all HIV positive mothers rather than only with a CD4 (type of white blood cell) cell count has fallen below a certain amount as a result of the infection.
Opening my latest NewScientist magazine, I was immediately drawn to its covering of the HIV case. Beside stating the majority of things I could learn via the news, this went into more depth of the sceptical response and future for this kind of treatment.
Mario Stevenson said 'At present, this can best be described as a functional rather than a sterilising cure' although also says that every baby of HIV positive mothers should receive 'triple-drug treatments'.Other beliefs, of Davis Margolis, are that the baby could have been a 'super-controller'- this means that the baby had a natural resistance to the virus, due to a fault in the gene that manufactures CCR5 receptors on white blood cells. HIV needs to attach to these receptors to successfully invade cells, meaning super-controllers are protected from infection from this nasty virus. This same mutation was involved in the only other 'cure' case for HIV- Timothy Ray Brown, mentioned above; the stem cells involved in his treatment were from the bone marrow from a super-controller.
Now, therapies are being developed that focus on these CCR5 receptors. Another hope for treatment is vorinostat- a drug that can 'flush out' HIV from its hiding places in cells and ARVs (antiretroviral drugs) can then be used to keep the virus at bay. Several countries are now giving ARVs to all HIV positive mothers rather than only with a CD4 (type of white blood cell) cell count has fallen below a certain amount as a result of the infection.
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