This year marks the 30th anniversary of the discovery of the human immunodeficiency virus (HIV), so it is with great excitement that the Aids community has received the news that a baby has been “cured” of the virus.
Scientists reported on Sunday that they have found the first case of an infant who has apparently been able to rid itself of HIV. They are calling it a “functional HIV cure” because the virus seems to be all but eliminated from the baby’s bloodstream – although they cannot be 100 per cent sure of total eradication from the body.
For three decades, Aids scientists have shied away from using the “c” word when it came to HIV. Unlike so many other potentially fatal viruses, the Aids virus had several stubborn tricks up its sleeve that made a cure seem virtually impossible.
Foremost among these tricks was the ability of HIV to hide away within the genetic material of a patient. No matter how many drugs or vaccines were deployed against freely-circulating virus, this hidden HIV – integrated within a patient’s DNA – was seen as virtually inviolable against attack.
Now researchers have discovered that they have perhaps witnessed a chink in HIV’s formidable armoury by scientifically documenting the rise and fall of the virus within the tiny body of a new-born infant.
The baby in question is now two and half years old and was born to a Mississippi mother who was diagnosed with HIV too late in labour for her to undergo the usual prophylactic treatment aimed at preventing the virus from being passed on during pregnancy and childbirth.
Scientists in the developed world can now limit the risk of “vertical transmission” of HIV from mother to child with something like 98 per cent confidence. They do this by dosing the pregnant mother with a cocktail of anti-retroviral drugs, delivering the baby by Caesarian section and preventing breastfeeding.
The aim is to lower the amount of virus that is freely circulating in the mother’s bloodstream and milk, and hence limit the risk of transmission during pregnancy, childbirth and lactation. New-born babies can also be given one of the antiretroviral drugs to lessen the risk still further.
However, in the case of the Mississippi baby the doctors decided to hit the virus will everything they could within hours of birth. Three powerful antivirals were infused into the baby within 30 hours of its delivery.
The baby today continues to be healthy, is not taking any antiviral drugs and has no HIV according to the standard blood tests. In effect, the scientists reported to the 20th Conference on Retroviruses and Opportunisitic Infections in Atlanta, Georgia, the infected infant has reached the state of a “functional HIV cure”.
The case is reminiscent of Timothy Brown, the so-called Berlin Patient who is thought to be the first and only adult to be cured of HIV, following a bone-marrow transplant. His transplant donor was an “elite controller” with a mutation in a gene called CCR5 which seems to prevent HIV from infecting key immune cells attacked by the virus.
However, Mr Brown’s case is very different to that of the Mississippi baby, who was only given anti-retroviral therapy, the standard treatment for HIV and Aids across the world.
Other scientists, however, are still sceptical of drawing too many conclusions over this one case. They would, for instance, like to see more hard detail in a properly peer-reviewed paper that responds to serious questions, such as whether the baby was truly infected with HIV in the first place.
“They have used very sophisticated tests to look for virus in the blood, but it can also hide elsewhere in the body,” said John Frater, an HIV researcher at Oxford University.
Antiviral drugs, especially when used as a combined cocktail of three or more, are good at eliminating free virus from the blood, but it only takes one or two viruses integrated in to the genetic material of an infected cell to cause further illness months or years down the line.
“It’s like playing Russian roulette; only one chamber contains a bullet – so if you remain HIV negative you don’t know if you cleared the virus or simply didn’t get infected in the first place,” said Professor Jonathan Ball of Nottingham University.
The Mississippi baby remains a solitary and enigmatic reminder that a genuine cure of HIV is still a long way off.
Timeline: spread of a deadly virus
1981 Infectious disease among gay men suffering from a rare form of pneumonia and skin cancer identified. Later reported as Acquired Immune Deficiency Syndrome (Aids).
1983 Luc Montagnier and Françoise Barré-Sinoussi, of the Pasteur Institute in Paris, identify a new retrovirus in a gay man suffering from Aids.
1984 Robert Gallo discovers the cause of Aids in a virus called HTLV-3.
1985 Hollywood actor Rock Hudson dies of Aids.
1987 AZT, the first antiviral drug to treat HIV, becomes available. UN launches global programme.
1990 Actor Ian Charleson, dies of Aids, the first UK showbusiness case.
1991 Queen vocalist Freddie Mercury dies of Aids aged 45.
1992 The first experimental combination therapies are introduced, where patients are given two or more anti-retroviral drugs.
1995 New type of anti-retroviral known as a protease inhibitor is launched.
2002 HIV/Aids is leading cause of death for people aged between 15 and 59.
2005 US health officials recommend use of antiviral drugs for post-exposure prophylaxis against HIV.
2007 Timothy Brown, receives bone marrow transplant and is later declared “cured”.
2012 Barré-Sinoussi seeks “cure research” to eliminate HIV.