Friday, 27 January 2012

H5N1 controversy from a scientist's perspective

What's all the fuss about? Flu isn't so bad, right?
Seasonal flu is an annoyance for most people but, in the young or elderly, or immunocompromised individuals, it can still be fatal. Each year, there are around 4,000 deaths attributed to flu in the UK, despite these people having access to health care and anti-viral medicines.

So why is everyone so worried about bird flu?
The H5N1 bird flu strain has so far caused 578 confirmed infections and 340 deaths, but all of these individuals were in close contact with infected birds. The big fear is if the strain gains the ability to be transmitted between humans, which would give it the potential to cause a global pandemic. But we don't know how likely it is that this will happen, so it's very much a waiting game. Because none of us have encountered this strain before, we have virtually no resistance and the outbreak could be much worse than seasonal flu. It has been estimated that the worldwide death toll could be around 150 million and, because the strains are constantly evolving, we can't make a vaccine until the epidemic begins. The best we can do is stockpile anti-virals and put in place contingency plans for what to do if the worst case scenario should materialise.

What's this about scientists making a transmittable version of the bird flu virus?
Scientists want to understand how the virus might make the leap into being transmittable between humans and, to do this, they have created a version of the virus which can be passed between ferrets. Ferrets are a good model for flu in other mammals so there is a good chance that this virus would also be able to spread between humans (but this isn't known for sure). The two papers in question have not yet been published and there have been calls from the US government for the journals in question, Science and Nature, to censor specific details about how the research was done in case bad guys use it to reverse-engineer a bio-weapon.

So the scientists have played God and created a killer virus just because they can
Let's get this one out of the way first. It is terrifying to see just how many web pages come up if you Google 'H5N1 playing God'. Do people honestly believe scientists are power-crazed maniacs doing really stupid things for the sake of it? Because it simply isn't true. This bird flu research was designed to give us a better understanding of how a potentially deadly virus might emerge naturally and go on to kill millions. Similar research into flu has led to some awesome discoveries that better prepare us to deal with this disease. For more information, here is an article by a scientist behind one of the bird flu papers explaining why he believes this work to be so important.

These papers contain methods that can easily replicated by those that would like to use flu as a bio-terror weapon
A well accepted way to create strains that can be transmitted between animals is to repeatedly grow the virus until it accumulates the mutations that will allow it to be passed on by itself. This is effectively happening in nature right now and many believe it is a matter of time before the bird flu virus does it outside of the lab. We need to understand how this could happen in order to prepare for a situation in which it does. And failing to publish these papers won't stop terrorists from attempting this method if they really want to but it isn't a quick and simple task.

But they could use the mutations detailed in the paper to reverse-engineer a deadly strain
It's been reported that all of the mutations leading to these new strains are already published - that's because the same mutations have already been seen in the wild, albeit separately. A person with enough knowledge of the flu virus would most likely be able to make an educated guess as to how to go about engineering a similar strain but even an expert would find recreating the virus to be a mammoth task. Generally, if you've put all your effort into following the terrorist career path, you probably haven't had the time to become an expert on complicated viral genetic manipulation.

How can scientists even run the risk that someone will use this information for evil purposes?
Because the dissemination of information is a cornerstone of science. Censorship is a slippery slope which could lead us to a point where legitimate scientists cannot access information that could help their work and be of benefit to others. However, it is unlikely to provide a barrier to those intent on doing harm. If we are going to start restricting what information can be published among the scientific community, we need to know that the restrictions will work and that they are being imposed for the right reasons, rather than as a knee-jerk reaction to the slightest whiff of concern. The laboratories at the centre of this controversy have agreed to a 60 day halt in their work so these concerns can be discussed - this is an effort to show they are taking the situation extremely seriously but some have voiced worries that it is simply an empty public relations gesture. But any bad feeling between the scientific community and the public needs to be addressed - it helps no one if scientists adopt a 'we know better than you' attitude and refuse to justify themselves.

Is the work really of any benefit, though?
Predicting how scientific advances will help us in the future isn't always possible - some of the biggest discoveries in science have emerged when no one was expecting them to. Sometimes in science it is necessary to accumulate a critical level of unusable information before something comes of it and anything that improves our understanding of a disease such as bird flu can only be a good thing. So perhaps this bird flu work will lead to a better vaccine or drug treatment, perhaps it won't. Some people have suggested that it will allow us to better monitor the virus, allowing us to predict when it might start spreading between humans. In theory, this is a great idea but, unfortunately, it relies on quick and reliable reporting of infections and they are currently occurring in parts of the world not well known for their organisational skills when it comes to keeping track of viral infections.

It is inevitable that some of these strains will get released by accident and we'll all die
Safety measures in every category 3 laboratory are extremely tight, training is extensive, and every scientist I've met takes safety very seriously - none of us want to infect ourselves, after all! We all need to consider the risks versus the benefits. Yes, dangerous work does go on in scientific laboratories. No, it is not inevitable that there will be an accidental release of something deadly.

But the work isn't even happening in the highest biosafety level labs
In the country where this work was conducted, bird flu can be used in category 3 laboratories rather than the stricter category 4 facilities (used to study diseases such as ebola). This isn't an indication that the scientists in question are being stupid, it is an indication that they have considered all the possible risks and have gained permission from the relevant agencies for this work to go ahead. But I personally do find it slightly surprising that a cat 3 was used - I know in the UK, our bird flu work takes place in cat 4 labs.

And it has been reported that there are no armed guards protecting the virus!
This is true, universities and research institutes don't tend to station people with machine guns at every entrance. Yes, if armed terrorists stormed the labs, they could potentially steal these strains. But, come on guys, we can't start having armed guards stationed in all the places that everyone's currently panicking about, only to move them on when the next sensationalist newspaper article pops up. Preparing for real threats (such as the natural emergence of bird flu) is surely better than living in fear of something extremely unlikely happening?

If it gets out, this strain will kill 80% of those infected
It is surprising how much this statistic is reported. Yes, nearly 60% of the reported bird flu cases have resulted in death. But the problem here is the word 'reported'. Only those who are very, very sick go to hospital - when was the last time you reported mild cold symptoms to your doctor? So we don't know how many people have been exposed to bird flu but haven't become sick. The death rate is likely to be much lower than 60% - possibly less than 1%, in fact (see this PNAS article discussing the fatality rate, amongst other things).

There is no treatment or vaccine available
Current anti-virals are active against the H5N1 strain and there are vaccines that provide some protection against H5 strains. But it is true that, if there was a global pandemic, it would likely take 4-6 months for a vaccine against the strain to be formulated and distributed.

Nefarious governments are deliberately doing this work to create weapons
There isn't much arguing with conspiracy theorists who believe the world leaders are out to get them. But I can tell you that I've met few scientists who'd be willing to act as minion to some shadowy government organisation intent on killing off half the world's population. That probably isn't much comfort if you've already convinced yourself that the government and all scientists are inherently evil. In truth, very few of us are evil – if we were, we’d have chosen alternative career paths such as banking.

Image: Cybercobra at en.wikipedia

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