There is another new bird flu.
- H7N9 Bird Flu Cases Reach 21 In China; Death Total Unchanged At Six
- More bird flu cases reported in China
- New deadly bird flu virus infects at least 20 in China
The NPR article is quite good:
This 'bird flu' is not that bird flu. But many of the same basic principles still apply (srsly, read that article).
There is no reason to freak out about this 'new' bird flu yet. It does not appear to be transmitting human-to-human, and as I said in the previous article, 'death rates' from infection in impoverished regions of China are not necessarily analogous to the entire population.
However this bird flu is demonstrating quite nicely why scientists artificially evolved mammal-to-mammal transmissible 'bird flu' in the lab last year. Vaccinate people against these variants before they ever evolve. Nature is telling us 'Hey, I know you guys were focusing on the H5N1 virus, but the H7N9 guys can cause trouble tooooo!' We have the technology to do something about it. To stop it. We know how to make workable influenza vaccines.
... Or we can just worry about terrorists and wait for Nature to do what it does-- Mutate, explore new uninhabited niches, and select.
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I don't think I follow. Why are you assuming these cases are all from "impoverished regions"? While I wouldn't be surprised if access to medical care was an important reason for the high case fatality rates, that probably only explains part of it. Otherwise, wouldn't you expect the case fatality rates for 'seasonal flu' to be astronomical in these regions?
Could explain a bit more why you think the gain-of-function experiments are so important? Why do you think they tell us here, and what does that have to do with a vaccine?
Also, I think it's worth pointing out that we have trouble making a really good seasonal flu vaccine. It's hard to see why are you so confident that it would be so simple in a scenario where we have so much less information.
Hmm, I can't respond to the bit about impoverished regions, but with respect to the gain of function experiments, one of the things touched on in the NPR article is the fact that while they observed some changes in the H7N9 sequences that may permit infection in mammals, we don't really know what most of those changes would be (although the ferret experiments that became so controversial at least gave us some ideas to work with). We also don't know what other changes to avian influenzas are needed to make them mammal-to-mammal infectious. Beacuse of that, we don't even know what to look for in the samples we've collected - we could be getting early warnings of an avian influenza that is one or two changes away from mammalian infection, one that we could be preparing a vaccine for, but we don't know enough right now to recognize that because most of the research hasn't been done.
...As for a vaccine, any warning is better than no warning (even knowing that we need to work with H7N9 strains would be a huge help), and a vaccine that is 50% effective against a pandemic strain is a lot better at reducing a) infections, b) morbidity (severe illness) and c) mortality than having no vaccine at all.
Pat, I don't know if you remember the TV press coverage from the first bird flu epidemic... anyway, the BBC certainly featured footage of children playing football with dead birds - basically, children and adults likely receiving very high doses of a new bird flu. I think the video I'm thinking of was from rural Turkey... That's probably not representative of the kind of exposure dose (and route!) that people in more economically active regions are going to get, and dose may be an important factor.
Also, with existing circulating flu strains, you wouldn't expect to get high death rates all the time, because a certain proportion of the population are immune. However, add a new strain to a population...