Credit ECDC – 125 years of Pandemic History
Note: This is one of a continuing series of preparedness blogs for this year’s National Preparedness Month. You can search for NPM14 (or last year’s NPM13) to find additional entries.
# 9058
While the timing, source, or severity of the next pandemic is unknowable, history tells us that influenza pandemics come along several times each century, making it very likely we will see another one sometime in the not-to-distant future.
Although a novel strain of influenza is considered the most likely contender, we’ve seen evidence over the past decade that non-influenza viruses – like SARS and MERS – have pandemic potential, as well.
Last February, in Influenza Pandemic As A National Security Threat, we looked at a threats assessment by the Director Of National Intelligence that included:
Worldwide Threats Assessment – published January 29th, 2014,
(Excerpt)
Health security threats arise unpredictably from at least five sources:
- the emergence and spread of new or reemerging microbes;
- the globalization of travel and the food supply;
- the rise of drug-resistant pathogens;
- the acceleration of biological science capabilities and the risk that these capabilities might cause inadvertent or intentional release of pathogens; and
- adversaries’ acquisition, development, and use of weaponized agents.
In December of 2012 the U.S. National Intelligence Council released a report called "Global Trends 2030: Alternative Worlds" that tries to anticipate the global shifts that will likely occur over the next two decades (see Black Swan Events). Number one on their hit parade?
Global Trends 2030's potential Black Swans
1. Severe Pandemic
"No one can predict which pathogen will be the next to start spreading to humans, or when or where such a development will occur," the report says. "Such an outbreak could result in millions of people suffering and dying in every corner of the world in less than six months."
The threat of another influenza pandemic is consistently ranked higher by most governments than a major cyber/terrorist attack, solar flare, or nuclear/WMD war – and is considered all but inevitable by many experts.
Despite the known risks, pandemic preparedness over the past few years has largely fallen by the wayside.
The declassification last year of a 2009 Northern Command Pandemic Plan (see SciAm story Pandemic Flu Plan Predicts 30% of U.S. Could Fall Ill) briefly caught the attention of a number of news organizations and websites with its estimates that during a moderately severe pandemic 30% of the population could fall ill, 3 million could require hospitalization, and 2 million Americans could die.
Although a certain amount of surprise was registered in these media reports, these are roughly the same numbers that were being openly discussed by local, state, and federal agencies during the pandemic planning phase of 2006-2008.
Credit - HHS Interim Pre-Pandemic Planning Guidence: Community Strategy For Pandemic Influenza Mitigation In the United States.
In fact, in 2008, the HHS outlined their vision of the likely impact in the United States of a severe and a moderate pandemic (see A Tale Of Two Scenarios). As you’ll see, the numbers of hospitalizations anticipated during a severe pandemic is quite a bit higher than the Northcom plan.
The HHS defined 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.
Pandemics, like hurricanes, are measured on a five point scale, with a CAT 5 pandemic – as bad or worse than 1918 – at the top of the scale. While there are many similarities between the hurricane and pandemic scales, there is one aspect where they differ greatly.
With Hurricanes, there are physical limitations that keep the storms from growing much stronger than 200 mph winds. Category 5 storms start at 156 MPH, and these storms are only capable of intensifying about 35% above that wind speed.
There are no such restraints on a severe pandemic. While a 2% CFR indicates a Cat 5 pandemic, so does a 5% or 10% CFR. Yet, the difference between the impact of these three CFRs would be enormous. Although the 1918 pandemic is often used as a model for the next severe pandemic, doctors and scientists generally admit that the Spanish Flu isn't the worst that nature could throw at us.
The thing about pandemics is, even after one starts, you never know how bad it is going to be until it is over. And even then it can take years to sort our just how bad it really was. Experts continue to wrestle with the toll of the 2009 H1N1 pandemic.
A pandemic can start out mild, and over time become more virulent – as did the 1918 H1N1 pandemic - or it could look really serious at the start, but prove milder than expected (as we saw in 2009).
While we can’t know when the next pandemic will arrive, or how bad it may be, we can prepare for a `reasonable-worst-case’ scenario – which is probably somewhere on the order of the 1918 Spanish Flu. To that end, the HHS has a number of pandemic planning toolkits available on their Flu.gov website.
The federal government cannot prepare for or respond to the challenge of a flu pandemic alone. Your community can develop strategies that reduce the impact and spread of pandemic flu.
Faith-Based & Community Organizations Pandemic Influenza Preparedness Checklist (PDF – 68.91 KB)
Lista de Preparacion para una Pandemia de Gripe Tanto para Organizaciones Comunitarias como Religiosas (PDF – 268 KB)
Community Strategy for Pandemic Influenza Mitigation (PDF – 10.3 MB)
Plan Now to Be Ready for the Next Flu Pandemic (PDF – 213.55 KB)
The Next Flu Pandemic: What to Expect (PDF – 226.83 KB) (excerpts below)
Their advice (and this is for before a pandemic threat becomes imminent).
Over the past 18 months I’ve written a number of pandemic preparedness blogs, including what the United States government is doing to prepare for a possible pandemic. You can revisit these at the following links:
The Pandemic Preparedness Messaging Dilemma
Pandemic Planning For Business
CDC: Pandemic Planning Tips For Public Health Officials
H7N9 Preparedness: What The CDC Is Doing
Admittedly, we may not see another severe pandemic for years, or even decades. But we are entering the winter respiratory season in the Northern hemisphere, and we have a full plate of novel influenza viruses we are watching for development – including H7N9, H5N1, H10N8, and H5N6.
Since it is impossible to predict when the next pandemic will occur, it makes sense to incorporate pandemic planning into your family, community or business disaster plans now, and in the future.
