Four things you should know about the HIV "cure" before you get too excited

The baby might not even have been infected in the first place.

The story everyone is talking about today is the HIV "cure" - the Mississippi baby who, after being blasted with a cocktail of anti-viral drugs at birth, is now, at two years old, apparently virus-free. But when reading the euphoric news stories about it here, here and here, you should bear the following in mind:

1. The baby may not even have been infected in the first place

Here's a weird section in the NYT version of the story. Have a read of the following two paragraphs - are the doctors certain or uncertain that the baby was infected?

“The one uncertainty is really definitive evidence that the child was indeed infected,” said Dr. Daniel R. Kuritzkes, chief of infectious diseases at Brigham and Women’s Hospital in Boston.

Dr. Persaud and some other outside scientists said they were certain the baby — whose name and gender were not disclosed — had been infected. There were five positive tests in the baby’s first month of life — four for viral RNA and one for DNA. And once the treatment started, the virus levels in the baby’s blood declined in the pattern characteristic of infected patients.

The tests are pretty good, but are not usually trusted as a basis for confirmed diagnosis at that early stage. It is normal practice to confirm positive tests at 6 weeks. But as this baby had already been treated by then, lowering its viral load (negative tests came back at 29 days), it would have been difficult to do this. There is a very small chance the baby was not infected.

The virus may not have yet taken a hold on the baby's cells in a permanent way. Here's the WSJ:

Cells in the baby "may have been infected—there was virus around," said Steven Deeks, an AIDS researcher at University of California at San Francisco. "But the cells being infected weren't the type that become long-lived reservoirs."

There is also a small chance the baby was immune to HIV anyway. Around 1 per cent of Caucasians in the US are naturally immune.

Now, these are small chances, but then this baby is an outlier. It was not part of a large study where such anomalies are ruled out. The scientists have said it is unlikely to be replicable. Any way you put it, the baby itself is an anomaly.

2. This "cure" has already been found, and has been used on newly-infected people since 1987. Even if the baby was infected, today's news would simply extend it to newborns.

Today's news applies only to babies. Newborns at that. And it's not really a new method - rather, it's the same idea as PEP: if you have only just been infected, you might avoid HIV if you are immediately given a large amount of anti-HIV drugs. What the scientists confirmed today is that, in terms of emergency treatment, newborns are the same as newly-infected people. 

Here's the NYT again:

“That goes along with the concept that, if you treat before the virus has had an opportunity to establish a large reservoir and before it can destroy the immune system, there’s a chance you can withdraw therapy and have no virus,” said Dr. Anthony S. Fauci, the director of the National Institute for Allergy and Infectious Diseases.

(Oh, and if you were wondering, someone has actually been cured of AIDs before. This was a man called Timothy Brown, a leukemia sufferer who received a bone-marrow transplant from a donor genetically resistant to HIV.)

3. This would not be breaking much ground in preventing HIV in newborns anyway, because we have a solution for that

In countries with access to top-notch medical care (ie western countries), the transference of HIV from mother to child is extremely rare. This is because mothers are treated with antiretroviral therapy during pregnancy - a very effective way of preventing HIV in newborns.

4. Newborns in countries without a solution for that probably wouldn't get this treatment anyway

In countries without access to top-notch medical care, there is no reason that this treatment would be available where antiretroviral pregnancy treatment isn't.

So what does the news mean? Well it means that a few babies in countries with access to this sort of care but whose mothers have somehow slipped through the net of normal practice can be saved. Joyous news. But not quite as joyous as everyone seems to be making out.

UPDATE: This blog originally said that HIV tests at birth couldn't be accurate, but this applies only to antibody tests. The tests on DNA/RNA, which were done in this case, have a greater (although not 100 per cent) degree of accuracy.

HIV cure: not necessarily.. Photograph: Getty Images

Martha Gill writes the weekly Irrational Animals column. You can follow her on Twitter here: @Martha_Gill.

Yu Ji/University of Cambridge NanoPhotonics
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Nanoengine evolution: researchers have built the world’s smallest machine

The engine could form the basis of futuristic tiny robots with real-world applications.

Richard P Feynman, winner of the Nobel Prize in Physics in 1965, once remarked in a now-seminal lecture that a time would come where we would “swallow the doctor”. What he meant, of course, was the actualisation of a science-fiction dream – not one in which a universal cure-all prescriptive drug would be available, but one in which society would flourish through the uses of tiny devices, or more specifically, nanotechnology. 

First, a quick primer on the field is necessary. Nanoscience involves the study and application of technologies at an extremely tiny scale. How tiny, you ask? Given that one nanometre is a billionth of a metre, the scale of work taking place in the field is atomic in nature, far beyond the observational powers of the naked human eye.

Techno-optimists have long promoted potential uses of nano-sized objects, promising increases in efficiency and capabilities of processes across the board as a result. The quintessential “swallow the doctor” example is one which suggests that the fully-realised potential of nanotechnology could be applied to medicine. The idea is that nanobots could circulate our bodily systems in order to reverse-engineer the vast array of health problems that threaten us.

It’s natural to be sceptical of such wild aspirations from a relatively young field of study (nanoscience unofficially began in 1959 following Feynman’s lecture “There’s Plenty of Room at the Bottom”), but associated research seems to be gaining widespread endorsement among prominent scientists and enthusiasts. Ray Kurzweil, Director of Engineering at Google, thinks a booming nanotechnology industry is crucial in the creation of a technological singularity, while futurist and viral video philosopher Jason Silva believes the technology will help us cure ageing.

The high-profile intrigue surrounding nanotechnology means that word of any significant developments is certain to stimulate heightened interest – which is why researchers’ achievement in building the world’s tiniest engine this month is so significant.

Reporting their results in the journal Proceedings of the National Academy of Sciences, the University of Cambridge researchers explained how the nanoengine was formed and why it represented a key step forward in the transition of the technology from theory to practice.

The prototype nanoengine is essentially composed of charged particles of gold, bound by polymers responsive to temperature in the form of a gel. The engine is then exposed to a laser which beams and heats the device, causing it to expel all water from the polymeric gel. The consequence of this is a collapsing of the gold particles into an amalgamated, tightened cluster. Following a period of cooling, the polymer then begins to reabsorb the water molecules it lost in the heating process, resulting in a spring-like expansion that pushes apart the gold particles from their clustered state.

"It's like an explosion," said Dr Tao Ding from Cambridge's Cavendish Laboratory. "We have hundreds of gold balls flying apart in a millionth of a second when water molecules inflate the polymers around them."

The process involved takes advantage of the phenomenon of Van der Waals forces – the attraction between atoms and molecules. The energy from these forces is converted into elastic energy, which in turn is rapidly released from the polymer. "The whole process is like a nano-spring," said Professor Jeremy Baumberg, who led the research.

Scientists have been tirelessly working towards the creation of a functional nanomachine – one which can effortlessly swim through water, gauge its surroundings and communicate. Prior to the research, there was a difficulty in generating powerful forces at a nanometre scale. These newly devised engines, however, generate forces far larger than any previously produced.

They have been named “ANTs”, or actuating nano-transducers. "Like real ants, they produce large forces for their weight. The challenge we now face is how to control that force for nano-machinery applications," said Baumberg.

In an email exchange with New Statesman about the short-term and long-term goals in bringing this engine closer to a practical reality, Baumberg said: “It allows us for the first time, the prospect of making nano-machines and nanobots. The earliest stage applications we can see are to make pumps and valves in microfluidic systems. Microfluidic chips are really interesting for synthesising pharmaceuticals, biomedical sensing and separation, as well as many other biochemical processes.

“But all pumps and valves currently need to be made with hydraulics, so you need a pipe onto the chip for each one, limiting strongly the complexity of anything you do with them. We believe we can now make pumps and valves from the ANTs which are each controlled by a beam of light, and we can have thousands on a single chip. Beyond this, we are looking at making tiny nanomachines that can walk around, controlled by beams of light.”

The embedding of nanobots into all facets of culture is still a long way off, and researchers will need to find a way of harnessing the energy of nanoengines. However, the prospect of one day seeing the fruition of nanorobotics is worth all the patience you can get. The tiniest robot revolution has just begun.