Friday, April 21, 2006

Bye, Bye Birdie! (or, Don't Fear the Flu)

The national and international media have proven their power. Much of the world's population has been frightened by them into believing there is an imminent health threat to them from birds. It's primarily an international problem right now, but as soon as you start seeing the first headlines screaming "BIRD FLU ARRIVES IN NORTH AMERICA" (sadly, even NPR news, which you would expect better from, is subject to the "ratings wars"), you'll find the same thing here as in other places. People are afraid to buy chicken. They are afraid of ducks in ponds. They are worried about their pets coming into contact with birds. A meat trucker lost his job in Italy because people weren't buying chicken, and he killed himself and his family!

In a world with bird populations in the 10s of billions, and the human population exceeding 6.5 billion, 103 people have died since 2003 from the H5N1 virus and all of them lived their lives with birds all around them (as pets and livestock).

Unfortunately, many people don't read very far beyond the headlines and if that were all you read, you would have good reason to have these fears. I don't blame the medical establishment for this nearly as much as I do the free press, which is all about selling copies and garnering viewers. A scary headline is much more effective than a truthful one. Hell, if I wanted more people coming to my blog, I would be wise to write terrifying articles about the end of the world. (And, in fact, I will have an upcoming story in which I will tell everyone exactly when the apocalypse will be. I do know and I will reveal it. So keep coming back)!

The fact is - IF avian flu were to mutate to a flu that could easily be passed human to human and IF the H5N1 virus were to, in the course of evolving, retain it's current mortality rate, THEN you would have something to be concerned with. None of this has happened, and there is nothing the average person can do to effect, one way or another, it happening. And the fact is, the world is over-due for another flu pandemic. The last one was in 1968 (the Hong Kong Flu), rushed around the world, and was roughly as deadly as our usual seasonal influenza. It just infected a lot more people worldwide. And the next pandemic, whenever it comes, may not be based on birds or H5N1. There could be another flu virus, even as I write, that is out there and mutating into a flu that will infect many people. No one knows.

It's good to be informed. But being informed means reading beyond the headlines, and usually means digging deeply into a story and finding out what multiple sources say about that story. Here is what you need to know about this particular story right now. Read it (but even here, don't just read the headline - take 3 minutes of your time and read the whole story), and then go about your life and concentrate on some REAL health issues in your life - like what you are stuffing into your face today, how much you plan on exercising, your exposure to excessive sunlight, and how much time you waste watching mind-numbing television "news" shows.

6 comments:

Impatient Patient said...

Dear John

THis is what I found out about the rotavirus- and why it has poky things.....

Feel free to erase- I am just thrilled and wanted to share. I have a night off- as off as one can with teenagers.

They use the word PIRATE in the article too....


Anatomy of a child killer
(Filed: 15/09/2004)


Scientists now know how a virus creates havoc and how to stop it, reports Roger Highfield

Under the gaze of an electron microscope, the virus looks strikingly beautiful: a 20-sided geometrical shape that bristles with 60 spikes. Although the football-shaped virus is tiny, measuring just 100 billionths of a metre across, it is a child killer.


Beautiful but deadly: the rotavirus, with its array of athletic protein spikes - the 'keys' it uses to 'unlock' cell walls

First discovered by Australian scientists in 1973, the rotavirus lurks in the intestine and is the most common cause of severe, dehydrating diarrhoea and vomiting in children worldwide, accounting for about six per cent of all deaths under the age of five.

Now atomic snapshots of the virus in action have been produced by a team at Children's Hospital Boston and Harvard Medical School, led by Dr Philip Dormitzer, offering hope that more effective "second generation" vaccines can be developed to help save half a million children each year in the developing world.

Published in the journal Nature, the study marks a major advance in the understanding of how viruses cause infection, and reveals the best parts of the virus to use as a vaccine to protect the body from attack.

Like all other viruses, a rotavirus is a chemical that lies on the borderline of life. Its blend of protein and genes (in the form of the primitive genetic material RNA) has a simple mission: to infect intestinal cells, pirate their machinery and turn them into virus factories.

The virus can kill as a result of the efficient way it has evolved to spread from person to person.

Using three strategies, it triggers severe diarrhoea and vomiting: it makes a protein toxin that causes diarrhoea; it kills cells that normally mop up fluid in the gut; and it interferes with nerves that control digestion. As a result, each gram of faeces from an infected person contains up to one hundred billion viruses.

Many viruses are cloaked in fat so they can "dissolve" through the membrane of a target cell. Lack of this fatty membrane makes the rotavirus more resistant to detergents, which means it can cope better with hygiene but also that it must use a different strategy to penetrate cells.

The key to its invasion strategy lies in the outermost of the three layers of a rotavirus, the main target of the new work. "The outside layer is like a landing apparatus and is stripped off in the course of entry," said Dr Dormitzer. "Its job is to get the innermost portions - the genes and the replication machinery - inside the cell."

The landing apparatus uses 60 "spikes" - each consisting of a cluster of molecules of the protein VP4 - to begin the invasion. To study this protein "key" which the virus uses to open host cells, the team wanted to use a technique called X-ray crystallography.

First, Dr Dormitzer and his colleagues would make crystals of VP4. Then they wanted to measure the way the crystals scattered X-rays and, from the pattern, deduce the structure of the protein down to the last atom.

They found a way to mass-produce VP4 by putting the genetic recipe for the protein in a virus that could be grown in caterpillar cells: as the virus grew, so did their stocks of the precious protein.

But their mass-produced VP4 did not form crystals. To overcome this, Dr Dormitzer and his colleagues smashed apart VP4 using enzymes, separating the part that makes up the spike's "head" from part that makes up most of its "body".

These protein fragments did crystallise. Comparison of the crystal structures obtained by X-ray crystallography with the spikes shown by electron microscopy images, obtained by BV Venkataram Prasad and colleagues at the Baylor College of Medicine, Houston, suggests that VP4 undergoes extraordinary gymnastics to invade a target cell.

When the rotavirus arrives in the intestine, digestive enzymes (notably trypsin) cause two of the three VP4 molecules in each cluster to form a rigid spike, positioning the spike "head" to bind to the surface of target intestinal cells.

In a second rearrangement, the spikes fold back on themselves, and VP4 forms a folded-umbrella consisting of three "panels". Dr Dormitzer and colleagues speculate that this folding motion enables the spike's "body" to puncture the cell membrane, allowing the virus to enter.

Details of the next stage are unclear. But once inside the cell, the virus consists of a double-layered icosahedral particle which is able to squirt genetic instructions in the form of RNA out of holes at its vertices. These RNA orders command the cell to make more viruses.

This work is useful for vaccine development because the "head" and "body" portions of the rotavirus spikes contain many of the targets that the body's protective immune system recognises when it attacks the virus. These can be used as the basis of a vaccine to train a healthy immune system to respond to the virus without encountering the real thing.

The "head" of the VP4 protein is stable at room temperature and easy and relatively cheap to produce with GM bacteria, Dr Dormitzer said. He believes the "body" is also hardy and efficient to make. A vaccine based on these proteins could be practical in developing countries where rotavirus causes the most serious illness.

First-generation rotavirus vaccines already exist. The only one that has been licensed, RotaShield, was pulled from the American market five years ago because of reported cases of intestinal intussusception, a potentially dangerous condition causing bowel obstruction. However, the vaccine may have triggered intussusception in infants who probably would have had it anyway later in infancy, the recent Sixth International Rotavirus Symposium in Mexico City was told by Dr Lone Simonsen, of the National Institute of Allergy and Infectious Diseases, Bethesda.

"A vaccinated and an unvaccinated infant may have a very similar risk of intussusception," she said. Her analysis of the influence of age at vaccination has downgraded the perceived risk of RotaShield, particularly if the vaccinations are completed within two months of birth.

These findings raise the thorny issue of whether First World fears about relatively rare side effects should hamper the use of an effective vaccine in the Third World. Today, the vaccine's licence is owned by BIOVIRx, a startup biotechnology company in Minnesota.

The work of Dr Simonsen has changed perceptions about safety, said Dr Leonard Ruiz, president: "BIOVIRx intends to market RotaShield in the developing countries where morbidity and mortality is the highest, but also in America and Europe."

RotaShield is based on a mixture of rhesus monkey rotaviruses, some of which have been modified by RNA gene-shuffling to incorporate a coat protein from a human rotavirus. Two vaccines based on a similar approach are now in phase-three clinical trials: RotaTeq, from Merck, is an attenuated virus based on shuffled RNA genes from bovine/human rotaviruses, and Rotarix, from GlaxoSmithKline, based on an attenuated human rotavirus strain.

Although it will take some years to use rotavirus proteins in a second-generation vaccine, this approach could be safer than live vaccines, says Dr Dormitzer. "The high concept I am pursuing is that by narrowing down the protein targets of the body's immune system, and understanding them thoroughly, we can make a cheap, safe, heat-resistant, and highly effective vaccine."

Impatient Patient said...

Of course you can use it!! I just thought that if I was going to comment on what I thought, I should probably look to see what I could learn. Viola!!!!!!

http://www.telegraph.co.uk/connected/main.jhtml?xml=/connected/2004/09/15/ecrkill15.xml

(This is the link to the article. )

I am just glad you made me laugh so hard, it was a good motivator to snoop. "Poky things" is not scientific, but it does give a different image than a sharp protruding appendage. And if it wasn't an appendage, then I would have been wrong in labelling it as such. Poky thing seemed so much more visual and safe.

Impatient Patient said...

BTW- I just figured out the cool looking virus thing on the CFS post- And it took me all day. Told you I am slow.

As well- I am jealous- you live in sunny CA and I have many friends and family there and wish I could be there. Ah well-- one day again I am sure.

John said...

I. Patient said: "As well- I am jealous- you live in sunny CA and I have many friends and family there and wish I could be there. Ah well-- one day again I am sure."

Family YES, friends... not really; a few. I'm quite the recluse and only the few friends who are able to understand that and deal with it have stuck with me over the years.

You'll make it out here. Funny how people look at the green on the other side of the hill. For me, it's Hawaii (specifically Maui). Maybe for them, it's Tahiti!

Anonymous said...

I just spoke to my CA relatives. I miss them terribly.

As for friends- let me tell you- I have had a hard time watching my life change over the last few years. I used to be the "mom" of the neighbourhood. I had a houseful of people and kids at all hours of the day and night. July 2001- oh yeah, that pretty much ended. With my husbands surgery and the ensuing craziness of the next four years, it has been hard to keep US together let alone let other people in. He has become a recluse and it is heartbreaking. I have no idea what your story is, but his was a workoholic who loved his work and that was his social life. When that ended it ended too. Now just a few people phone, and he will not speak to them as it reminds him too much of what is never to be again.

I have maintained ies to my friends and family with a lot of difficulty. I am a lot more negative than I ever imagined I could be. I am also a lot more proactive. SOmetimes that helps and other times it doesn't.

Part of the reason I blog is because I do believe this could happen to anyone and I want people to know that there is someone out there who gets it and is on their side. Too many times, even on the internet, people are accused of faking disease and disability by people who have no clue.

I also am pissed. I am pissed that my life is not what I thought it would be. I am even more mad that no-one can fix what is wrong with hubby.

Anyways- you can read about my sad and sorrowful tale on my blog- or not. Either way, know that I get recluse and I respect it.

How was American Idol tonite- this is one year I did not follow it at ALL....too much hockey and such at the start.

Take care John

Impatient!!

John said...

I.P. said: " He has become a recluse and it is heartbreaking. I have no idea what your story is, but his was a workoholic who loved his work and that was his social life. When that ended it ended too. Now just a few people phone, and he will not speak to them as it reminds him too much of what is never to be again."

Let's just say that you and my wife can relate, though I'd guess you're having it a bit harder than her. But who knows. I just say that because I not a complete recluse - but I certainly have the mindset. I'm disappointed in myself, my government, my world, my fellow Homo sapiens. and I have zero faith, so I have no "happy future" thoughts to fall back on. The only things that kind of keep me afloat are a) distractions such as blogging, video games, sports and b) trying to help relatives and my few friends when they ask for it (I try hard not to turn them down. I think this helps me).