Cytokine Storms and Swine Flu

As of this moment, there are 100,000 people likely infected with Swine Flu - H1N1 influenza in 48 of the United States. Of those, some 200 have been hospitalized, some needing intensive care treatment. An Assistant Principle of a New York public school died of it this weekend.

“CDC officials say around 100,000 people are likely infected with the new flu strain in the United States and the Director of the Centers for Disease Control said the 5,123 confirmed and probable cases and six deaths in the United States were "the tip of the iceberg.”

Unlike the seasonal flu, we are seeing relatively few cases or hospitalizations in people over 65," the CDC said. Usually flu kills the elderly and people with chronic diseases. When family members are questioned, it seems clear that children and teens are more prone to infection than older adults. "People under 18 are more likely to have infections when another person in the family is infected.”

The reason this is getting so much attention is that this mirrors the effects of the global pandemic of 1917-1918 which killed more than the Black Plague of the 14th century. IN that pandemic, the effect somewhat mirrors what we are seeing with this global outbreak of Swine Flu. One of the key indicators of a severe prognosis is the disproportionate number of young, healthy victims as compared to those who usually succumb to these flu outbreaks. Said the CDC this weekend, “While it appears to be mild, it is affecting a disproportionate number of children, teenagers and young adults.” This is what has everyone worried. In the 1917-1918 pandemic, the exact same scenario played itself out. The 1917 variant was mild but its evolved genetic progeny was a planetary wide killer- mostly of young, healthy people.

The reason for such a result is found in the body’s response to viral and bacterial infections. When the strain is particularly virulent – or able to cause a massive whole body infection very quickly, the body fights back vigorously to survive the onslaught.

The body has a very complex defense mechanism involving many different simultaneous immune responses. One of these responses is called the ‘cytokine’ response.

When the immune system is fighting pathogens, cytokines signal immune cells such as T-cells and macrophages to travel to the site of infection. In addition, cytokines activate those cells, stimulating them to produce more cytokines. Normally, this feedback loop is kept in check by the body. However, in some instances, the reaction becomes uncontrolled, and too many immune cells are activated in a single place. This response is called a “Cytokine Storm”. The precise reason for this is not entirely understood but may be caused by an exaggerated response when the immune system encounters a new and highly pathogenic invader. Cytokine storms have potential to do significant damage to body tissues and organs. If a cytokine storm occurs in the lungs, for example, fluids and immune cells such as macrophages may accumulate and eventually block off the airways, potentially resulting in death.

There is considerable evidence that in the 1917-1918 pandemic where the deaths were concentrated within populations of young, healthy people, of which the Cytokine Storm was a major cause of death. It turns out that being young and healthy is the major contributor to this too-vigorous immune response to a virulent viral organism. In normal flu outbreaks the mortality profile is opposite because the very young and older have immune systems that do not respond with such vigor and the Cytokine Storm is avoided. In these cases, the victims normally die of extended elevated fever and secondary infections such as pneumonia.

The Swine Flu – 1H1N – event was declared over and that it had run its course by the media two weeks ago. But the disease seems to have a mind and a plan of its own. The wise person will keep an eye on the horizon for the dark clouds of a building Cytokine Storm and pray it goes away for real or 2010 may become a nightmare not easily forgotten.

Crying Wolf or Sounding The Alarm?

Before I launch into the eye of the viral tempest with a discussion of Cytokine Storms (to be posted in a day or so), let me preface this with a warning on news stories about this Level 5 state of potential global pandemic. The key word is: potential. The US Centers for Disease Control, the World Health Organization and other nations are all responding in a by-the-book manner to the swine flu, H1N1 potential as a global threat. But the media is now busy with alternate stories on either a full-blown panic or sharp criticism of the response by world governments. The key to all this is simple: ignore the media totally and go directly to the various sites such as the CDC and your local state and county internet outlets. That way, you sidestep typically uneducated media opinions and focus on the scientists and physicians who typically do not speak in a panic mode but in factual terms.

The idea here is that since no one is a prophet, NO ONE knows how this will eventually pan out. The fear is that it will blossom into another 1918 global pandemic with far more terrible results. On the other hand, it may be nothing more than just one of the normal flu bugs which together kill some 36,000 people each year. Today, H1N1 flu is far below even that threat – as of today the number of individuals infected number only 331 in 11 nations and the global death toll as of today stands at 10 – and yet the clear alarm has been sounded. The point is – no matter what opinion you may have, opinions have absolutely no value – it is simply a game of figures and best-guesses.

This issue is dominated by sheer, unemotional statistics. And according to these statistics, if the numbers we see out of Mexico are truly accurate, the statistics favor that this flu is not your ‘standard annual flu’. As we will discuss in the next post, a normal flu virus predominantly kills the very young or old or compromised. However, H1N1 exhibits characteristics that favor a pandemic species - such as statistically targeting young people. Hence the greatest minds in virology and epidemiology have declared a planetary Pandemic Alert of 5, one notch below an actual full blown planetary pandemic. It’s not that H1N1 has done any appreciable damage on a widespread scale – it is that it exhibits the species and statistical characteristics to become very bad. Hence the alarm has been sounded without the associated fatality numbers. It is not that it is dangerous – but that it can be. It is much like sounding the tornado alarm before the funnel cloud is actually spotted and the wisdom of that can be argued – but it is a classic case of taking the most safe and conservative approach to the potential.

It can well be that this threat will go the way of avian flu or SARS (severe acute respiratory syndrome) and just fizzle out. Or, alternately, avian flu can still become the agent of pandemic - or – it will be still some unknown agent many years from now. Every expert just knows one thing for certain – it will eventually happen and tens of millions will die. The point is – real life is not a movie. There are no scripts. We must not ridicule those who try and warn us with the facts and make us more prepared. And of you really want to know what is going on, book mark this site and this site and stay on target with the real facts minus the emotion and opinions.