Tuesday, June 30, 2009

Swine H1N1 influenza: The worst is yet to come

Posted on Monday, June 29, 2009 at 10:27AM by

By now, alert reader, you know the details. The entire world is engulfed with swine flu. Even though the WHO dragged its feet in the final days before the Phase 6 declaration, we all knew this virus had achieved pandemic status.

But in this nation, the press, with the exception of the New York Times and local newspapers, has for the most part ignored the story since early June's pandemic declaration. So let's catch up on recent events:

  • More people died in this country last week from swine flu than died in all of April and May combined.
  • Same thing happened last week.
  • Deaths in this country are doubling every week.
  • It is spreading deeper into corners and pockets of America where it was not before.
  • The Muscular Dystrophy Association has cancelled every single one of its MDA kids' summer camps, coast-to-coast. Other organizations are following suit.
  • The average age of a dead American from swine influenza is 37.
  • The CDC is telling us this virus is moving faster than the 1957 or 1968 pandemics did. Understandable, with quick, easy air travel and interstate highways. But so far, it is not moving with the ease of seasonal flu. So far.

What is difficult to gauge is just how we should categorize this pandemic from a "Saffir-Simpson" standpoint. Drs. Fukuda and Chan of the WHO says this is a "moderate" pandemic. That would place it in the range of 1957's H2N2 pandemic, which killed 70,000 Americans and around 2 million worldwide. (If the 1957 pandemic hit today, it would kill 122,000 Americans).

A moderate pandemic would also nest 2009's swine H1 pandemic into high Category 1 or low Category 2 status on the US charts. As you have seen from the charts I have published before, the case fatality rate from a Category 1 pandemic is up to 90,000 deaths. A Category 2 pandemic is anywhere from 90,000 to 450,000 deaths.

The case fatality rate from swine H1 is currently .0045, or .45%. That means that for every 2000 people who get sick from swine H1, 9 will die. Extrapolating this rate out over the probable three pandemic waves, we could see as many as 400,000 Americans die from swine H1.

There, first time in print. Unchecked, and at the current rate of fatality, some 400,000 US residents could die. And most of them would be under age 50.

Can you imagine what devastation that would cause to young families? To the economy? To the economic future of the Republic? Is it any wonder, then, that the US government has arranged for some 600 million doses of swine flu vaccine, to be administered in two shots for each American at three week intervals?

Well, two shots spaced three weeks apart for anyone under age 50. For those of us carrying AARP cards, we get one shot -- one shot, Vasily -- and one shot only. At least that's the current thinking. Nice to know that neither 1946 nor 1951, when subtracted from 2009, equals 50. As you know, those were the last two aberrant outbreaks of H1N1 that caused either a partial pandemic or increased fatalities. So the CDC should limit jabs to one for anyone ages 64 and older. that covers anyone who went through both 1946 and 1951.

Now the public health people would quickly say, "Wait! We think a million Americans have been exposed to swine flu! And only 127 have died, based on positive test results. Your projections are WAY out of line! And you're inciting panic!"

Am I?

First, let's take that "one million Americans" stat. I absolutely agree that at least one million Americans have been exposed to the virus. But in what quantity (titer) of virus? How many particles?

We know that a normal flu season will only infect up to a fifth of Americans. Why only a fifth is a matter of continual speculation. It is probably a combination of vaccination successes, cleanliness, partial immunity, and damn good genes. There is a growing community in the scientific and public health fields that believes some people are genetically doomed to always catch the flu, while others are genetically predisposed to never catch it. Most of the rest of us are constantly in the middle.

Pandemic calculations are different. The US government's own pandemic projections indicate 90 million infected, 45 million presenting serious illness, and then factor in the appropriate Case Fatality Rate (CFR). This is opposed to the 5% to 20% who gets seasonal flu every year, according to the CDC. Roughly 36,000 to 40,000 people annually die from seasonal flu. A CFR of .001.

But last year, the CDC only tested less than a quarter of a million people for flu, even though some 60 million may have been infected.

From the CDC Website:

During September 30, 2007 – May 17, 2008, World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories in the United States tested 225,329 specimens for influenza viruses.

And another statistic: In the 2007-08 flu season, only 83 deaths were reported of children ages 18 and under from influenza. Eighty-three hardcore, confirmed pediatric deaths out of 36,000 estimated seasonal deaths from flu.

So the figure of 36,000 people annually dying from flu is an old stat that has pretty much entered the lexicon as fact. But certainly not every single one of those 36,000 people were tested for flu! Else the CFR for seasonal flu would be around 16%. So the experts at CDC have algorithms to determine such things.

OK so far? Let's continue.

The estimate of 36,000 deaths annually from seasonal flu is based on extrapolating the numbers of infected and looking at the CFR of those who tested positive and died, and then reapplying that CFR to the overall guesstimate of infected. And you really never know how it all turned out until it all turns out.

The calculations are really no different with pandemic flu. We've earlier mentioned the equations. Let's do the calculations together:

  • According to the CDC, one million Americans have been infected with swine H1.
  • That means 330,000 Americans (nearly one-third) have become ill, even mildly so.
  • That means 165,000 people have been seriously ill enough to (hopefully) stay home.
  • That means an estimated 1,485 Americans have potentially died from swine flu or its complications to date.

How many Americans have died from pneumonia, or from other life-threatening complications, and were never diagnosed with swine H1? What are the chances that, from late March until today, that over a thousand Americans have died from swine H1 and those deaths have gone undetected and unrecorded?

I'd say, pretty damn good. Look at the massive, gaping holes in surveillance. Look at the people who have not been swabbed. Look at the immuno-compromised in this nation.

I would speculate that a significant number of deaths from pneumonia since March 2009, and many MRSA-related deaths, and significant numbers of death from "respiratory complications" since mid-March could, in actuality, have been swine flu-related. As of last week, we have 127 documented deaths from some 27,717 confirmed or probable cases. We know that 99% of all influenza A being typed in America today -- right this minute -- is testing positive for the pandemic strain.

From the CDC:

During week 24 (June 14-20, 2009), influenza activity decreased in the United States, however, there were still higher levels of influenza-like illness than is normal for this time of year.

  • Three thousand two hundred eighty-six (41.9%) specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.
  • Over 99% of all subtyped influenza A viruses being reported to CDC were pandemic influenza A (H1N1) viruses. (bold mine)

OK, so we have 127 confirmed swine H1 deaths. Subtract 127 from 1,484 and we have 1,357 deaths. We have, according to the Census Bureau via Wikipedia:

The U.S. Census Bureau lists 3,140 counties or county-equivalent administrative units in total. There are on average 62 counties per state.

It would take less than one death in half the counties in America to reach that number. What are the odds that one pneumonia-related death, or one MRSA-related death, has occurred in each county in the United States since the inception of this swine H1 outbreak/epidemic/pandemic?

Pretty daggum good, I would say.

At the 2000 U.S. Census, only 16.7% of U.S. counties had more than 100,000 inhabitants. That would make 525 counties (let's round up in case some county had 90,000 people). What are the chances that each of these 525 counties had, say, three people die of pneumonia since late March that went untyped? And even if they only had one apiece in the past three months, that would leave the remaining thousand cases to be spread over some 2,600 counties, parishes, etc.

Not to mention the possibility that many swine H1 deaths may have been mistakenly attributed to seasonal flu. I have great difficulty in believing that only 2 persons have died in Florida from swine influenza. Not when you look at the figures coming out of Latin America and you realize Miami is the gateway to Latin America -- not to mention Orlando's Disney World.

Miami-Dade County has over two million residents. It has reported, to date, 305 positive swine flu cases. Yet only one death-- a 9-year old child -- has been reported? Ridiculous. Florida has recorded 941 cases, yet it has documented only two deaths from swine H1. Using the nationwide CFR, Florida should have experienced 4 deaths. Using New York's CFR, it should have 10 deaths. Do the numbers yourself. Check the CDC H1N1 Website and see your state's results.

This is probably as much a function of the diligence of state and local health departments to test suspected influenza cases as anything else. New York has a higher CFR because they have been looking for the virus and they had a good health commissioner. So good, he now runs the CDC, promoted by Obama in the middle of New York's problems.

I think you can see where I am taking you. We are missing many deaths. You cannot speculate that we have a million swine flu cases without a concurrent speculation that we are missing many, many deaths. And as I have just proven, it takes less than one death per county over two months to fill in those gaps in surveillance. This is the danger in trying to look so closely at the actual number of positive swabs that you miss the Big Picture.

That Big Picture includes monitoring large employers for signs of absenteeism. It includes enlisting Chambers of Commerce and the US Department of Labor to check employee absenteeism. It means coordinating with governments at the local and state level as well as the Federal government to monitor absenteeism on a daily basis.

Keep swabbing and keep testing, absolutely. But do not solely rely upon swabs to tell you who is sick. And do not tell me, or anyone else, that we only have 127 dead from swine H1 so far in this nation.

Effect Measure has a sensational piece regarding the current state of the flu pandemic. It includes references to risk communication expert Dr. Peter Sandman, who was very kind in his praise of one of my recent blogs. It concludes this way:

Public health authorities up north are counting on having some advance warning on how bad things can get by seeing what is going on in the southern hemisphere. But the virus may not give anyone that luxury. Countries like Australia, Argentina and Chile are already getting hammered and the virus seems to be increasing in places in the north at the same time. In other words, we have yet to take the measure of this virus.

Whatever that measure turns out to be, I feel pretty confident that "mild" won't be a word to describe it.

My good friend Mike Coston has also weighed in on the topic. Both Revere at Effect Measure and Mike reference the piece by Helen Branswell of the Canadian Press. Helen's work is always superior, and her article is spot-on perfect. Read her piece (you just passed the link).

Get set to get absolutely hammered this fall.

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