Thursday, July 31, 2008

A Tale Of Two Scenarios

# 2194

Earlier this week I highlighted a video of an ethics seminar held by by the Minnesota Department of Health and the University of Minnesota Center for Public Health Preparedness.

Here is a link to that presentation.

Ethics in the Worst of Times: Rationing to Protect the Public's Health during a Severe Influenza Pandemic

This event took place on June 5, 2008.

Contained in the first video was a slide graphically illustrating each state's planning assumptions about the type of pandemic they are preparing for.

As you will see, there is a wide divergence of opinion.

Roughly 20% of our states are preparing for a severe 1918-style pandemic, while 20% are preparing for a moderate (some might even say `mild') event.

For the remaining 60% of our states, the severity level they are preparing for is ambiguous.

States in White are planning for a moderate pandemic, orange colored states are planning for a severe pandemic, and the plans for gold colored states are ambiguous on this point.

This graphic also appears in the powerpoint presentation by Dorothy Vawter, PhD. entitled Age-Based Rationing in a severe Pandemic. This chart is current as of Sept.2007.

I'm aware that Michigan has recently released an addendum to their pandemic plan, and that may move them into the ambiguous column.

While no one can know what the next pandemic will bring, the U.S. federal government has adopted the attitude that it is prudent to prepare for a severe 1918-style pandemic.

The HHS defines a severe pandemic as:

    • An attack rate of 30% (90 million Americans sickened)
    • 50% (45 million) requiring outpatient medical care
    • 11% (9.9 million) requiring hospitalization
    • 745,000 requiring mechanical ventilation
    • 1.9 million deaths (2.1% fatality ratio)

A moderate (1958/68-like) pandemic is described as follows:

    • An attack rate of 30% (90 million Americans sickened)
    • 50% (45 million) requiring outpatient medical care
    • .9% (865,000) requiring hospitalization
    • 64,875 requiring mechanical ventilation
    • 209,200 deaths (.23% fatality ratio)

In other words, while the number of people affected doesn't change, a severe pandemic is envisioned to be about 10 times worse than a moderate one.

A quick check of some of these state's pandemic plans reveals that the definition of a `moderate pandemic' varies greatly. We'll look at two states (Georgia & South Carolina), and compare their assumptions with the Federal guidance for a pandemic event.

Georgia, with a population of roughly 9.3 million people, assumes the following:

Most noticeable here is the estimated attack rate of less than 15% (half of the Federal estimate for a moderate pandemic).

Since the rest of their numbers are based on a percentage of the number made ill by a pandemic virus, those numbers are proportionately lower as well.

South Carolina, with 4.3 million residents, acknowledges an attack rate of up to 35%, but their case fatality ratio is a little more than 1/3rd of 1%.

The upshot of all of this is that if we see a severe pandemic, tens of millions of Americans will reside in states that only prepared for a moderate event.

South Carolina, which is only expecting a maximum of 16,800 flu-related hospitalizations could, under the federal scenario, find that 150,000 of their residents could need hospital care. And instead of 5,000 deaths, they could be looking at 28,000 flu-related fatalities.

Similarly, Georgia could find that instead of 1.14 million people clinically ill, that they must deal with nearly 3 million. Instead of 22,000 requiring hospitalization, they may find the demand is closer to 300,000. And the number of deaths could exceed 58,000 - not the 6200 assumed in their plans.

The Federal assumptions are guidelines, and states are free to use their own judgement in deciding what kind of crisis to prepare for. If we see a mild pandemic, then I suppose those states that prepared for a moderate event will feel pretty good about themselves.

But if the next pandemic is like 1918, or worse . . . then states that prepared for a moderate pandemic are likely to find their plans inadequate for the task at hand.

And if that happens, then there are going to be a lot of state and local officials with some explaining to do.