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Being healthy ups the risk of H5N1 infection
Posted by Raven on November 12th, 2005
Lots of things have been written about H5N1, how bad it is, how deadly it is…and much of the wording used in medical journals and infection control circles is beyond understanding (unless you work in the field). This is the first article I have seen that defines exactly why H5N1 is SO VERY dangerous. It’s not like the flu. It’s not like the common cold. It’s far worse.
FRIDAY, Nov. 11 (HealthDay News) — As concern mounts over the potential spread of avian flu to humans, researchers believe they’ve discovered one reason why the infection can prove so deadly.
Experiments with human cells have found the H5N1 virus can trigger levels of inflammatory proteins called cytokines and chemokines that are more than 10 times higher than those that occur during a bout of the common flu.
This massive increase in cytokine and chemokine activity can inflame airways, making it hard to breathe. It also contributes to the unusual severity of the avian flu, which can result in life-threatening pneumonia and acute respiratory distress.
This happens FAST.
Reporting in the Nov. 11 online edition of Respiratory Research, Michael Chan from the University of Hong Kong and his collaborators in Vietnam looked at the levels of cytokines and chemokines in human lung tissue exposed to the H5N1 virus.
They compared protein levels induced by strains of the H5N1 virus with levels induced by a more common, less virulent human flu virus, called H1N1.
Chan’s team found that H5N1 induces more pro-inflammatory proteins than H1N1. After infection with H5N1, levels of the chemokine IP-10 in bronchial epithelial cells reach 2200 picograms per milliliter , compared with only 200 picograms per milliliter in cells infected with H1N1. Similar results were found for levels of other chemokines and cytokines.
That’s a little bit of medical mumbo jumbo…but just look at these numbers- you can see the difference. This is what they call STORM.
One expert said the findings are in line with symptoms seen so far in patients infected with the avian flu strain.
“These findings fit with what we see clinically,” said Dr. Christian Sandrock, an assistant professor of pulmonary critical care and infectious diseases at the University of California Davis. “This is what we would expect with this virus.”
When the H5N1 virus comes into contact with the cells of the trachea and small air sacs in the lungs, it drives up the production of these cytokines, Sandrock explained. The cytokines trigger inflammation, a normal response by the body to help fight the virus.
“The problem is that sometimes the inflammation can be so bad there’s collateral damage,” he said. “That collateral damage can cause inflammation and damage to your lungs enough so that you are unable to breathe, and you get acute respiratory distress.”
The findings provide a scientific reason for what is being seen clinically, Sandrock said. “But there’s still a lot we don’t know,” he added.
Clinically speaking, this is a very difficult disease to manage. Pneumonia itself isn’t hard to treat because we usually find the source and treat that. But with H5N1, the source is known but the remedy isn’t. It doesn’t go away.
Interestly and most worthy of attention:
“This is basically a cytokine storm induced by this specific virus, which then leads to respiratory distress syndrome,” Osterholm said. “This also makes sense of why you tend to see a preponderance of severe illness in those who tend to be the healthiest, because the ability to increase the production of cytokines is actually higher in those who are not immune-compromised. It’s more likely in those who are otherwise healthy.”
So being healthy and having a good immune system is no guarantee you’re going to survive this. In fact, the healthier you are, the more you’re apt to catch this thing if it goes human. Damn.
November 12th, 2005 at 6:43 pm
Ya know, this kinda reminds me of Steven King’s The Stand. Super Virus spreads throughout hte world killing off 99% of the population. Ofcourse that is a fictional story, but this new flu sounds pretty scary in its own right. Hope they get a vaccine or some other treatment quickly before this thing mutates into a human contagion.
November 12th, 2005 at 6:55 pm
[...] Raven over at And Rightly So has a post about the Bird Flu that is popping up all over. What is scary about it is that, according to the articles Raven has quoted, the disease is actually more deadly for healthy people. Being a nurse she narrowed down the mumbo jumbo and put it in layman’s terms: So being healthy and having a good immune system is no guarantee you’re going to survive this. In fact, the healthier you are, the more you’re apt to catch this thing if it goes human. Damn. [...]
November 13th, 2005 at 6:09 am
Time will tell what happens with this.