December 4 Flu Update
There are 2,000 dead birds in the Ukraine.There continue to be outbreaks among birds in Romania, as well.
Very interesting AP article on bird flu "hype" and what it is doing to business models in biotech.
"There are so many unknowables and a lot of hype," said AG Edwards analyst Al Goldman. "The avian flu potential is something that you can't get your arms around because no one knows if - or when - a pandemic is going to happen."Another backgrounder: How is the travel industry preparing for bird flu...inherent dilemmas including preparing without effect behavior NOW--something public health is facing, too.
Editorial from Seattle Post-Intelligencer on recent efforts in that region in pandemic planning. Excellent point--pandemic preparations would help a region in any disruptive disaster. All the more reason to move ahead, and not to get hung up on how like a pandemic might be.
The Sunday Times reports on the Vietnemese doc who said Tamiflu was useless in his experience--which we ran yesterday.
“We place no importance on using this drug on our patients,” she said. “Tamiflu is really only meant for treating ordinary type A flu. It was not designed to combat H5N1 . . . [Tamiflu] is useless.”
Washington DC media outlet reporting flu induced "frenzy" in hand sanitizer sales.
While most businesses feel pandemic flu is a major threat, many know they are unprepared, this survey says.
If you've been watching for a while, you've noticed a strong debate about whether using alum as an adjuvant in flu vaccines will boost the immune response, thereby lowering the required dose and stretching vaccine supplies. Helen Branswell is, as always, a welcome addition to this issue. As always, a must read.
"There's no free lunch," Treanor insists.
"You want to go down the road of adjuvants, then you have to accept the potential risks of increased side-effects.
"We don't know a lot about adjuvanted flu vaccines and how that would play out in some kind of mass vaccination campaign in hundreds of millions of people. And we know very, very little about alum-adjuvanted flu vaccines in children."
Effect Measure weighs in on this story. He has an interesting observation added in:
Some virologists worry that H5N1 is not very immunogenic and hence raising an immune response with any vaccine might be difficult. This is bad news on two counts: it means we might not be able to develop a vaccine at all, and the virus might be unusually virulent because of the lack of an immune response. Only further study (or worse, actual experience in a pandemic) will settle that question, but it is my guess this virus is not defective in immunogenicity, so an effective vaccine still seems like the best long range strategy.I'm just asking, but if there is a lack of an immune response, doesn't that contradict the cytokine storm theories?
Another excellent article from Canada on the concept of societal disruption--or, put another way, why do you need two weeks of food for a flu pandemic?
Japan is planning to stockpile Tamiflu at its embassies around the world.
Recombinomics says that genone sequences in Herons show evidence of recombination.
ProMed on Ukraine and Romania.
Also ProMed. First, the confirmed death reported yesterday in Indonesia. Second, a nurse in Vietnam may have H5N1--only explainable by H2H if true. (Note with caution that this same patient appears to have started a cluster elsewhere, leaving the clear fear that his flu is very transmissible.
Newsweek/MSNBC has an interview with David Nabarro, referred by Crofsblogs.
Here's the direct link.
Also, I didn't see it, but there was a segment on 60 minutes about the bird flu as well.
posted by Orange @ 10:29 PM
2 Comments:
o&b: As I noted in answer to this question at EM, the immune system is a very complex machine and has many parts. The vaccine response (which is what people refer to when talking about immunogenicity in this context) is the potency of the viral protein antigen to induce a protective titer of neutralizing antibodies. This is humoral immunity (antibodies produced by B-cells). However there is also a very complex cell mediated immunity, some of it innate (doesn't depend on the exact nature of the antigen) and some of it adaptive (like the humoral system, responds to specific antigens). Exactly what happens in a "cytokine storm" isn't completely understood, but generally it can be viewed as a dysregulated system of cell to cell signaling via chemicals (the cytokines). Ordinarily cells send out signals that other cells (e.g., those involved in inflammation, which is the body's way of recruiting protective cells to deal with an invader) should come and help out. If there is an over reaction (dysregulation) the outpouring of inflammatory cells can itself be a killer response (the cytokine storm). This is a vast oversimplification of a complicated and as yet poorly understood phenomenon, however.
Hope that helps (some).
Thanks it does. Appreciate your explanation.
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