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CDC, State of Florida confirm blogs on H1N1v prospects in Fall

Forgive me as I smile while frowning.

As you recall, back on June 29 and in my blog titled "The Worst is Yet to Come," I mentioned some rather startling figures. I mentioned that, absent a successful layered strategy, the number of American dead from swine H1 could reach 400,000.

A few weeks ago, I gave a presentation to the Institute of Internal Auditors. In that presentation I also mentioned that, in Florida alone, the death toll could possibly reach 27,000 people.

My calculations are not rocket science; anyone with an understanding of calculating such numbers has risen to agree with me. One such comment came from a fellow named Bill Suydam, in his blog named "Health Spectator." The blog in question takes a critical look at my work and comments:

It is worth noting that McPherson’s calculations of CFRs does not take into account the presumed high number of people who contract swine flu and never so much as see a doctor, thereby reducing the number of reported cases vs. the number of reported deaths from swine flu. However, since he appears to be using published numbers from the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) his method is consistent. We cannot propose a better method, but one must realize that the increase in case fatality rates may be apparent rather than real.

If the apparent increases are real, however, there is cause for alarm. Certainly Kawaoka’s findings of lung damage as opposed to mere invasion of the nasal passages and pharynx by seasonal flu could explain a higher mortality rate from the new swine flu.

Thanks, Bill. I found your blog about me to be very fair and balanced. On to the latest news: Via the AP, dateline Tallahassee:

Pandemic could infect millions with H1N1 virus

FL State Wire
Published: Yesterday

TALLAHASSEE, Fla. (AP) - A top state medical official says 5 million Floridians could contract the swine flu within a year if the virus follows the pattern of previous pandemics.

Acting state epidemiologist Dr. Richard Hopkins said Thursday that pandemics are deadly because so many people get sick. He notes that as many as 30 percent or more of the population was infected in previous pandemics.

Officials at the Centers for Disease Control and Prevention says they've been estimated this pandemic could be along the lines of the 1957 Asian flu outbreak, with similar infection rates.

Florida has reported that 22 residents infected with the H1N1 virus have died, including 10 in the last three weeks. Officials counts say at least 2,900 Floridians have been sickened from the virus. However, experts say adding in unreported illnesses would make the actual number much higher. Officials expect more cases after public schools open next month.

OK, so now a respected Florida government official is talking some serious numbers. Bravo and Well Done, Dr. Hopkins. I can only assume you are getting some flak for this story, and will get more at your Orlando conference next week. Hang tough. You are right and correct.

The next story is also from AP, dateline Atlanta. It says:

Swine flu could strike up to 40 percent in 2 years

ATLANTA — U.S. health officials say swine flu could strike up to 40 percent of Americans over the next two years and as many as several hundred thousand could die if a vaccine campaign and other measures aren't successful. (bold mine)

Those estimates from the Centers for Disease Control and Prevention mean about twice the number of people who usually get sick in a normal flu season would be struck by swine flu. Officials said those projections would drop if a new vaccine is ready and widely available, as U.S. officials expect.

The U.S. may have as many as 160 million doses of swine flu vaccine available sometime in October, and U.S. tests of the new vaccine are to start shortly, federal officials said this week.

The infection estimates are based on a flu pandemic from 1957, which killed nearly 70,000 in the United States but was not as severe as the infamous Spanish flu pandemic of 1918-19. But influenza is notoriously hard to predict. The number of deaths and illnesses would drop if the pandemic peters out or if efforts to slow its spread are successful, said CDC spokesman Tom Skinner.

A CDC official said the agency came up with the estimate last month, but it was first disclosed in an interview with The Associated Press.

"Hopefully, mitigation efforts will have a big impact on future cases," Skinner said.

In a normal flu season, about 36,000 people die from flu and its complications, according to American Medical Association estimates. Because so many more people are expected to catch the new flu, the number of deaths over two years could range from 90,000 to several hundred thousand, the CDC calculated. Again, that is if a new vaccine and other efforts fail. (bold mine)

The World Health Organization says as many as 2 billion people could become infected over the next two years — nearly one-third of the world population. The estimates look at potential impacts over a two-year period because past flu pandemics have occurred in waves over more than one year.

WHO officials believe the world is in the early phase of the new pandemic.

First identified in April, swine flu has likely infected more than 1 million Americans, the CDC believes, with many of those suffering mild cases never reported. There have been 302 deaths and nearly 44,000 reported cases, according to numbers released Friday morning.

Because the swine flu virus is new, most people haven't developed an immunity against it. So far, most of those who have died from it in the United States have had other health problems, such as asthma.

The virus has caused an unusual number of serious illnesses in teens and young adults; seasonal flu usually is toughest on the elderly and very young children.

New swine flu illness have erupted through the summer, which is also unusual, though cases were less widespread this month. Officials fear an explosion of cases in the fall, when children return to school and the weather turns cold, making the virus easier to spread.

Associated Press Writer Frank Jordans in Geneva contributed to this report.

I can't help but wonder if the public health establishments are being told to start preparing us for what we might see in the autumn.  It is a refreshing change to see the talk beginning to better match the threat.

And as you might imagine, it is nice to be vindicated -- and my numbers validated -- by public health authorities and institutions.  Credibility is a slippery thing sometimes, and especially since I am not, as Mr. Suydam points out, a virologist.  So it is reassuring to me professionally and personally that my numbers are valid.

May you find my advice and speculation equally valid.

Reader Comments (3)

Scott,

I had no problem with the WHO's worldwide 2 billion cases figure---in fact, I posted that one on my website May 7.

What threw me was the AP report that the U.S. has already seen 1 million cases. That seemed awfully high, considering we hit the 10,000 (confirmed and suspected) mark around May 30.

Then I stopped to think about it. We went from 0 to 10,000 U.S. cases in 4-6 weeks. Almost two months later, is 1 million a realistic figure? I suppose so, when we assume that the number has always been higher than officially reported. We're no longer in "flu season," which works against such a number, but if we assume that infections simply continued unabated, 1 million should be quite doable.

Haven't yet read your report on Kawaoka's paper (I came across your site by Googling Kawaoka's name to find a copy of the paper and found one of your earlier posts criticizing him) but I have to agree with you that his reports of lung damage are a mite unsettling. And the start of Tamiflu resistance makes that more unsettling still.

Time for people to start paying close attention to diet, excercise, wise use of supplements and maybe avoiding crowds as much as possible. Right now, a strong immune system is the best defense.

July 24, 2009 | Unregistered CommenterBill Suydam

However, since he appears to be using published numbers from the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) his method is consistent. We cannot propose a better method,

Can't we ?

As for sound evidence based estimates of the CFR,
plase take a look at the recently published Wilson paper [1] that provides reasonable estimates of upper and lower bounds of pandmic H1N1 case fatality rate.

According to that Study, which, as a meta study takes into account several independent estimation methods the upper bound of the CFR (i.e. the most pessimistic estimate) is as low as 0.06 % (that is 6 in 10.000) which is one order of magnitude less than previous estimates of 0.5% and, BTW perfectly in line with seasonal flu CFR.

----------------
[1] N. Wilson
"The emerging influenza pandemic: estimating the case fatality ratio"
Free full text available at
http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=19255

July 29, 2009 | Unregistered Commenterh1n1_watcher

Dear H1N1 Watcher,
First, let us all hope it is from your keyboard to God's ears on the CFR!

A few comments.

First, a low CFR is what we are hoping for, but not necessarily what we should be planning for. In my blogs at Computerworld, I explain the concept of planning for one category higher than the event we are told to prepare for (the hurricane analogy). Even CDC is telling us the CFR could be in the hundreds of millions, and we have to listen to and respect our own public health establishment.

Second, I cannot find a pandemic in the era of even remotely reliable medical history (1830s pandemic to present) where the second wave was milder than the first. Assumptions have to side with the theory that the virus becomes more efficient and more virulent.

Third, the Wilson study does not, as far as I can tell, take into account misdiagnosed causes of death. An earlier blog of mine attempts to take that into consideration. I believe that as we get into larger and larger numbers, a pattern emerges. One cannot assume there are a higher number of "milder" cases and then take the total reported number of deaths as gospel. You have to account for missed deaths due to H1. The CFR was climbing as the virus was reaching its tendrils across the USA, stabilizing somewhere around .005, plus or minus.
To quote from the study:

"Sophisticated statistical methods have been proposed for obtaining adjusted CFR estimates using data from the early phase of an epidemic [20], and these result in adjustment for various time lags and an upward shift of the CFR. However, such adjustments would probably have little effect on the estimates presented in this article which are based on data from country epidemics which have progressed well beyond their early stages (e.g. the Canadian data). There is also the potential for under-recognition of deaths attributable to influenza in those with serious co-morbidities, but this can only be addressed by careful research studies and post-epidemic modelling to determine total excess deaths."

My takeaway from that is there is no reliable math to calculate deaths that were not correctly attributed to H1 in real-time. There actually is a way to do that, which the CDC performs. You take your baseline death rate, look for spikes in excess mortality and attribute that to the virus. But that reporting also lags, sometimes by weeks. So we are constantly steering by our own wake and not looking forward.

For all these reasons, it is absolutely prudent to plan for a more serious event.

I wanted to thank you again for the link. I shall read this again and attempt to obtain the document referenced in #20.
Scott

July 29, 2009 | Registered CommenterScott McPherson

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