bird flu
revere | February 24, 2009I'm not sure what to make of the report that scientists in Boston, California and the CDC in Atlanta have made monoclonal antibodies that protect mice against many different flu subtypes. Monoclonal antibodies are antibodies made by the descendants of a single immune cell (that is a single clone, hence monoclonal). Thus unlike natural antibodies, these are also monospecific, i.e., they are directed against one specific target. Our natural immune system "sees" a protein on the surface of the virus called hemagglutinin (HA), of which there are 16 broad subtypes and many, many variations within…
revere | February 11, 2009The Chinese like chicken. The biggest restaurant chain in China is Kentucky Fried Chicken (2300 in 500 cities). The source of supply is always close. China raises more poultry than any nation on earth. But that poultry also has outbreaks of bird flu, and there have been eight human cases in the last month. Any relationship? The eight cases are not clustered and appear sporadic. But the Ministry of Health has said the human cases appeared in areas where there was no reported bird flu, which puzzled them, since it is conventional wisdom that human cases result from close interaction with…
revere | February 10, 2009Nature has just published another new paper on the basic biology of influenza virus. Unlike other recent papers it doesn't purport to reveal the secret of why some flu (e.g., H5N1, 1918 H1N1) is so virulent and "normal" seasonal influenza much less so. Instead it involves a process and structures that are the same in both bird and human influenza viruses, which is one reason to pay special attention to it. The structural mechanism is important enough to be retained unaltered in viruses with diverse host preferences and it also becomes a potential target for drugs or vaccines that would work…
revere | February 9, 2009I am frankly baffled by a news release from Gideon Informatics, a company that describes its mission as developing and marketing "point-of-care medical-decision support applications that help reduce diagnostic errors." It claims to be "managed by an expert executive team and medical advisory board." Apparently they forgot to give this press release to their advisory board before releasing it:
Despite the recent fatal case of avian flu in Beijing, overall avian flu cases in humans worldwide have decreased 55%, from 88 to 40, from 2007 to 2008, according to GIDEON Online (www.gideononline.com…
revere | February 7, 2009It turns out that we were not the only ones musing on the relationship between the news business and the flu business. Dr. Michael Osterholm, is the Director of the Center for Infectious Disease Research & Policy (CIDRAP), and also Editor-in-Chief of the CIDRAP Business Source, a subscription newsletter offered to the business community on pandemic (and similar) matters. Dr. Osterholm's name has appeared here often, perhaps most memorably as the author of the "We're screwed" observation. A couple of weeks before my recent post he had written to the business community:
The collapsing…
revere | February 6, 2009For reasons other than this blog (I actually have a real life) I was reading a 1965 text by Leavell and Clark, Preventive Medicine for the doctor in his community: an epidemiologic approach, and found this on pp. 67-68 regarding tasks in a disease outbreak:
"Further spread must be prevented; the sick must be cared for, hospitalization must be provided, if necessary; the population must be told how to protect itself; inoculations may be required; and particular attention to the safeguarding of water, milk, and food supplies may be essential."
Concise and to the point. I wonder how much…
revere | February 5, 2009The question of reporting on flu comes up here from time to time and one of those times was a few days ago. In a post on the low path bird flu outbreaks in British Columbia's Fraser Valley we raised a number of questions we thought should have been asked by the Canadian Press's reporter. We drew a comparison with the exemplary reporting for the same wire service (Canadian Press) by Helen Branswell, generally regarded by flu folks as the best reporter on the subject (there are also other extremely good reporters, among them Maggie Fox at Reuters and John Lauerman at Bloomberg, to name just…
revere | February 2, 2009Yesterday there was a fairly long story from the wire service Canadian Press that wasn't written by their ace flu reporter, Helen Branswell. It carried the byline of Greg Joyce. I'll come back to why I mention this at the end of this post, but first, here's what it was about:
Three of four of the most recent avian flu outbreaks in Canada have broken out in British Columbia's Fraser Valley but despite years of trying to figure it out, they still can't explain why the valley attracts the virus.
In the latest outbreak, 60,000 turkeys were culled on an Abbotsford, B.C., farm last week.
Tests so…
revere | January 27, 2009On Sunday my friend and colleague from Fluwiki, DemFromCT, did me the honor of interviewing me on the front page of DailyKos. That's a pretty tall platform, being the most visited blog in the known universe (and beyond), so it's best to be absolutely clear when saying things there. I"m not sure I quite met that standard, but I'll let you judge for yourself, as I am cross-posting the interview below the fold. But this also gives me an opportunity to clarify one point that drew some justified comment. Here's something I said in the interview:
In the past I downplayed individual prepping for a…
revere | January 22, 2009Readers want to know what I think about the bird flu situation in China, where four human cases have been reported in the last couple of weeks. I haven't said anything about it so far, which is normal for me. I usually like to wait for more information. There are dedicated and smart flu bloggers out there who spend more time collecting scraps of information than I do. Check out fluwiki forum and CureEvents, for the latest word, all accurately reported by top rank flu bloggers like crof and Mike and a number of others (it is dangerous to start naming people because you inevitably leave out…
revere | January 18, 2009DemFromCT has Flu and You, Part II up over at DailyKos. As with Part I, it is well worth reading. It implicitly raises an extraordinarily important issue -- the crucial value of the public health infrastructure -- and explicitly lays out a vital part of it, the public health laboratory network.
Next week Dem plans Part III, where he will interview us on this. It is an opportunity for us to get our thoughts together on a subject we have often promoted but haven't spelled out. I'll keep you posted on the plans. Meanwhile, pop over to DailyKos and have a read.
revere | December 31, 2008Every couple of months a major flu paper appears purporting to reveal why the 1918 H1N1 virus was so horrifically virulent in comparison to the other pandemic viruses of the last century, H2N2 (1957 pandemic) and H3N2 (1968 pandemic). It's not just the H1N1 subtype of the influenza A virus that made it so deadly. There's still lots of H1N1 around, even as I tap this keyboard, but it isn't as virulent as the 1918 variety. Why not? If we knew the answer we might be able to spot a genetic change in circulating viruses indicating a turn toward virulence or find a drug or vaccine solution to…
revere | December 28, 2008As far as the world is concerned, if any day can be said to be bird flu's birthday, it's today. The disease of birds doctors call influenza A subtype H5N1 may have had a long gestation period, but we're not sure how long. A form of the virus deadly to poultry was isolated from a goose in southern China (Guangdong province) in 1996, marking the first time the highly pathogenic form of the H5 bird virus poked its head above water for us to see. How long it had "been around" before that we don't know. Then in May, 1997, a three year old tot in Hong Kong came down with a flu-like illness that got…
revere | December 19, 2008It should surprise no one that bird flu is back in Asia, not just in poultry but in people. That's because it's flu season and the bird flu virus, has been "out there" all along, simmering in the rich broth of aquatic and landbased birds. There are new outbreaks in India, China, Cambodia, and Hong Kong and deaths in humans in Cambodia, Indonesia and Egypt.
India:
Outbreaks have been confirmed in at least three states. In the last three days health authorities have ordered the culling of 9,373 birds in Malda (West Bengal) despite opposition by local residents, who have reacted to the measure…
revere | November 29, 2008Genetically modified crops is not a special interest of mine, which is a good thing because once you get into that controversy you are like the worker who gets his sleeve caught in the machine: before long you are dragged into the gears and badly mauled. I'm not reflexively against it. I recognize that what GM advocates have been saying has more than a grain of truth: we've been engaged in genetic engineering of crops since agriculture was domesticated. Modern genetic techniques have amplified that ability by orders of magnitude, but the result is the same. We are purposely altering the…
revere | November 24, 2008Public health scientists and professionals have human health and welfare at the center of our concerns. But we have learned that the human species is part of a tightly connected web of other living species and we are all roaming around in a common environment, the surface of the earth. Avian influenza is a good case in point. The influenza virus is mainly a parasite of birds but some forms also infect humans and some infect both. The influenza/A subtype designated H5N1 ("bird flu") is a case in point. It devastates terrestrial birds, like poultry, and when it infects humans it has a truly…
revere | November 15, 2008One of the good things about the pandemic flu threat (if you'll let me put it that way) is the stimulus it has provided for vaccine technology. While current flu vaccines are still mired in horse and buggy technology of egg-based production, all sorts of alternative ways of making antigen or stimulating an immune response are being worked on. Most of them involve the major antigens of the flu virus, hemagglutinin (the H part of subtype designation) and neuriminidase (the N part). They are on the viral surface and easily "seen" by the immune system. There is also a little bit of another…
revere | November 14, 2008The idea of stopping flu "at the border" has received almost uniformly bad reviews from public health experts. Once human to human transmission starts we won't be able to stop it by closing our borders, although we likely will cause the usual unintended consequences, like preventing vital personnel and supplies from getting to where we need them. At least if we do it in the usual ham handed way this administration is famous for. We learn via CIDRAP News that federal officials are still willing to give a "risk-based border strategy" (RBBS) a go, at least in the form of an exercise. Now, at…
revere | November 13, 2008If there's an influenza pandemic in the near future all bets are off when it comes to unplanned for consequences. Well, maybe not all bets. Right now the only oral antiviral likely to have any effectiveness in a pandemic is oseltamivir (Tamiflu), although how effective and how long it would retain any effectiveness is in question. But there's a lot of it out there and it will be taken in high volume and, either in its capsule form [oseltamivir ethylester-phosphate (OE-P)] or its active form [oseltamivir carboxylate (OC)], excreted into the sewer system in massive quantities (discussed here…
revere | November 8, 2008One nasty (and usually fatal) consequence of infection with bird flu (influenza A/H5N1) in humans is that the virus doesn't just infect the lungs but becomes disseminated to many different organs. We know that a bird-like receptor that the virus can use to get into cells is found in several other organs, including the lining of blood vessels and neural tissues. Central nervous system involvement is frequently a hallmark of fatal bird flu cases. The virus probably gets to a lot of other organs, as well. But how? An examination of the blood of a fatal case in a pregnant woman suggests answer…