Friday, May 8, 2009

When Pigs Fly

I’ve been meaning to write an article about influenza for a while now, and with the new Swine Flu pandemic it seems like as good of a time as any to do a little research into the subject. First, I should tell you that I don’t believe that I have ever contracted the flu, and as far as I know the only time I have ever been immunized was when my son was born. The reason I did it was to avoid accidentally passing on a sickness to the little guy, and as a new dad I was just about as freaked out and paranoid as I could be without lining my walls with aluminum foil and setting bear traps in the front entryway. So, I dutifully rolled up my sleeve, got my shot, and vowed at that time to look into the stats of flu, since so much time and effort seem to go into worrying about it and reporting statistics about the illness. Of course throughout history there have been several influenza pandemics, and the flu has tended to cull a bunch of people from the heard when things went south in the past. But how about now? How many people buy the farm every year after getting sneezed on by the guy behind them in line at Kinko’s? Should we really be worried?

First, here’s a little information about the flu itself. Influenza is a retrovirus, which means that it is not composed of DNA, rather it is an RNA (DNA precursor) virus. It only affects birds and mammals, so you don’t have to worry about getting your pet tarantula sick, and you won’t contract it from kissing your hippie roommate’s iguana. The flu infests a host where it then hijacks cells’ machinery in order to continually replicate itself. Meanwhile back at the ranch, the immune system kicks in and generally attacks the body making the host genuinely feel like cold poop. In severe cases when people have other conditions that tend to weaken their immune systems the flu can lead to pneumonia, which can then lead to death. The flu retrovirus transmits itself through the bodily fluids that tend to leak profusely out of the poor saps that contract the virus. There are three types of seasonal influenza – A, B and C. Type A influenza viruses are further grouped into subtypes according to different kinds and combinations of virus surface proteins. Among the many subtypes of influenza A viruses, currently influenza A(H1N1) and A(H3N2) subtypes are circulating among humans in every part of the world. Type C influenza cases occur much less frequently than A and B, which is why only influenza A and B viruses are included in seasonal influenza vaccines. Swine Flu and the Spanish Flu of 1918 are variants of the H1N1 or type A flu.

So what’s the big deal? You get the flu because some scumbag wiped his nose on the seat in the cab you just hopped into, and then you generally feel like garbage for a week or so. It’s at least a decent excuse to avoid work, right? You’re not going to die from it…or are you? Surprisingly, the statistics behind influenza transmission and mortality are a bit hand-wavy. After trolling the web for multiple sources, the consensus “feeling” is that in the U.S. an estimated 25-50 million cases of the flu are reported each year leading to 150,000 hospitalizations and 20,000-40,000 deaths. 25-50 million is a pretty big range, don’t you think? If these figures were extrapolated to incorporate the rest of the world, there would be an average of approximately 1 billion cases of flu, around 3-5 million cases of severe illness, and 300,000–500,000 deaths annually. Also, if we take these numbers at face value 40,000 deaths in the U.S. is almost identical to the number of people killed in automobile accidents every year. That seems surprisingly high to me considering there have only been two deaths in the U.S. so far from the scary new uber Swine Flu, and I never hear about regular flu deaths on the news like I do for automobile fatalities.

As far as the Swine Flu goes, as of May 5th there have been 403 cases of Swine Flu in the U.S., leading to two deaths. It is important to realize here that these are confirmed cases (hospitalizations). There is no way to know other than an educated guess what the number of people who have this type of flu is that just don’t go to the doctor. Mexico, the presumed origination point of this new strain, has reported 822 laboratory-confirmed human cases of infection, which includes 29 deaths. Still only a blip compared to the regular, old, run-of-the-mill, kill-half-million-people-every-year strain of the flu. Twenty-two countries have officially reported 1516 cases of influenza A (H1N1) infection so far. This virus was originally referred to as “swine flu” because many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs in North America. However, further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia as well as avian genes and human genes. It’s a bit of a mosaic bug. You may (or may not) be surprised to know that there was another Swine Flu scare in 1976. Check out this propaganda film released at the time. Bloody brilliant! However, despite the same government scare tactics one person died from the Swine Flu itself in 1976. But you’ll be glad to know that hundreds of Americans were killed or seriously injured by the inoculation the government gave them to stave off the virus. Nice.

The reason for the scare surrounding this strain (and the Bird Flu, SARS, the ’76 Swine Flu, and…etc.) is based on the great flu pandemic of 1918. In 1918 the Spanish Flu killed from 20-100 million people worldwide in a two-year reign of snot-filled terror. This was at a time when the worldwide population was only around 1 billion people, so the Spanish Flu had a significant impact on culling the herd. However, I think it is important to put the 1918 outbreak into perspective. Life in 1918 was very different than life in a modern society. Jonas Salk, the man who would go on to pioneer vaccines (thus, arguably saving more lives than any other human in history), was only 4 years old. There were no national radio stations, and television was not invented yet. The New York Times had just begun their home delivery service. Henry Ford created his assembly line just 4 years prior, so vehicles were not yet ubiquitous. Standards for hygiene were not the best. Worst of all the 18th Amendment (Prohibition) was voted on and passed by the idiots in the U.S. Congress. Not to mention the Red Sox were the top team, so there must have been some kind of tear in the fabric of reality. God was obviously punishing mankind. Modern communication, personal hygiene practices and advances in medicine all will work to minimize deaths caused by influenza outbreaks in the world today. If we start talking about other viruses like Marburg , Ebola, or some other unknown bug that sneaks out of a Department of Defense laboratory then that will be quite another story altogether.

O.K. I’ve thrown some large numbers out there, but I want to briefly mention some of the problems that I have with this data. I’ve searched all over Hell’s creation in order to get a good cross-section of flu statistics, and what I’ve found is that many sources aren’t really comparing apples to phlegm-covered apples. There are numerous statistics reported in articles and on the internet, and determining the actual study or survey on which an estimate is based is often difficult, even for statistics reported by health authorities or government agencies. Some flu-prevalence numbers use estimates of people diagnosed, others try to include estimated numbers of undiagnosed people, and it is often difficult to tell which is which. Global data has been collected from numerous sources, and the reputability and accuracy of each source cannot reasonably be completely confirmed. Some data comes from government agencies. Some comes from patient phone surveys. Other data is from various methods of estimation, and so on. Many estimates are computed from a small sample and then extrapolated to a larger population group, and this method has various inherent limitations to its accuracy especially when we’re talking about people that are just sick and not quite dead yet. Actual death data is a little more solid, but even that is up for debate as I will get to next.

Here’s a shocking bit of info that somehow has seemed to go unnoticed or has purposefully been ignored in the whole influenza discussion that has the potential to put the entire topic on its ear. As I was mining the plethora of information on the CDC website I found the National Vital Statistics Report on causes of death for the year of 2006. So, I did a search for influenza to see how it compares to the various bits of info that are floating around the internets. The category of “Influenza and Pneumonia” is listed as the eighth-leading cause of death in the U.S., just below Alzheimer’s and just above kidney disease. Looking a couple of pages further down the document the actual numbers of deaths is shown for the category. The category is split up between the number of deaths from pneumonia and the number for the flu. Number of deaths from pneumonia = 55,477. Pretty, friggin’ bad. Number of deaths from influenza = 849. What the? 849?!? Where did all of that “20,000-40,000 deaths” nonsense come from that we mentioned earlier? Well, this is where the real hand-waving starts when people talk about flu deaths. The flu virus can cause pneumonia, which then kills a lot of people. However, there are no fewer than 200 other medical conditions that can also cause pneumonia. Exactly determining the cases that are directly attributed to influenza is a dicey proposition at best. At worst, it is wildly misleading. In order to match the numbers of deaths that are widely reported (that 20,000-40,000 number) would mean that anywhere from 36% to 72% of all deaths from pneumonia are caused exclusively by the flu virus. Again, that is just a little too large of a span to lend any credence to the stat.

This leads one to ask if there is a reason for a statistical reporting bias towards large numbers of deaths from the flu. Although most reputable organizations use official independent statistics, some organizations may tend to quote higher numbers because either they see the condition every day and blindly assume it is highly prevalent, or to make the conditions they monitor seem more important in order to justify funding levels or even seek donations. Of course there are always the vaccine manufacturers and drug companies to point a finger at as well. At least from where I’m sitting the big, bad influenza bug isn’t as bad as the powers that be are making it out to be. Does it kill people? Of course it does. Do we need to be shutting down schools and businesses, wearing inappropriate face masks, and duct-taping our doors shut? Absolutely not. So, go ahead. Wipe your nose on your boss and feel free to hack up a lung on your next international flight. If you have the flu, your odds of dying from it are about the same as the odds of being wrongly declared dead by a social security data entry mistake. But you might just get your ass beat if you sneeze on me. So, you’ve got to weigh your options carefully.

1 comment:

TJ said...

Great post, as usual, Dan. It's just a tribute to how accustumed we have become to living in fear. Pathetic.

Maybe this herd does need some culling after all.