As avian or bird influenza (H5N1) spreads throughout bird populations across Asia and, recently, into Europe, health and government officials are warning the public of an impending pandemic that reaches beyond bird species and into the global human population. The unthinkable fact is that pandemic flu potentially threatens to kill tens of millions of people around the world; disrupting basic life services and causing a form of havoc in international healthcare systems that none of us have witnessed or, perhaps, can fully appreciate.

This analysis will examine not only the threat of avian flu, the general assumptions of a pandemic flu and how it could affect our society, but also the necessity for preparation by those businesses and institutions that are critical for a successful response to this approaching crisis.

Avian flu (H5N1) has recently been discovered in Western European nations and will undoubtedly make it way to Northern America in the near term. The current avian flu strain primarily infects poultry and other birds with devastating effects. The virus has cost Asian countries billions of dollars in the poultry industry. It has also proven to be equally lethal to humans, with a 50% mortality rate in individuals known to be infected with the H5N1 virus.

The U.S. Centers for Disease Control & Protection (CDC) defines a flu pandemic as a "global outbreak of disease that occurs when a new influenza A virus appears or emerges in the human population, causing serious illness and spreading easily from person to person." H5N1 presents two of the three essential ingredients to produce a worldwide influenza pandemic.

The third factor is for the virus to mutate just enough so that it can be easily transmitted from human to human. This meaningful shift has not happened yet. However, if it does, H5N1 will no longer be an avian or bird flu. Instead, it will be a human influenza capable of infecting hundreds of millions of people around the world.

As much as medical researchers, government officials and healthcare practitioners around the globe would like to know, no one knows for sure if the final mutation will occur with H5N1 or not. However, what scientists do know without a doubt is that a pandemic will occur. Just as tsunamis and category 5 hurricanes occurred in the past and have occurred again to devastating effect, pandemics have been visited upon world populations before and another will occur in the not-too-distant future.

There have been 10 pandemics in the past 300 years of world history. Three have occurred in the past 90 years. The last two occurred within a relatively short timeframe, 1968 and 1957, and were considered mild, producing only moderately elevated death rates in the U.S. The 1918 or "Spanish Flu" pandemic was far more devastating, causing 500,000 deaths in this country alone and at least 40 million deaths worldwide. While is uncertain if the next pandemic will reach the severity of 1918, it is imperative that all segments of society prepare for when, not if, it occurs.

To help plan a response, public health officials have developed several key assumptions about the impacts of a possible new flu pandemic. These assumptions are informed by previous events, particularly the 1918 pandemic.

• 30% of Americans will become ill.
• With only moderate impact, 856,000 people will require hospitalization over an 8-12 week period and there will be over 200,000 deaths.
• If the pandemic equals the severity of 1918, there will be 9.9 million U.S. hospitalizations and up to 2 million deaths.
• Government officials will likely close schools, along with a variety of other public places, and large gatherings will be cancelled for several weeks.
• People will be encouraged to limit their exposure to others and practice "social distancing".
• The business community can expect 25 to 30 percent of its workforce to be absent from their jobs for weeks at a time either from illness or caring for family members.

Under these conditions, businesses and governments would face serious challenges in maintaining critical infrastructure services, from providing healthcare to furnishing medications to supplying food and safe drinking water.

Here in the U.S., President Bush has recently asked for and received initial funding from Congress to modernize flu vaccine development and stockpile antiviral medication. While these efforts are good first steps, they are not a solution to our pressing health care response needs. It may take years to complete a timely pandemic flu vaccine and the usefulness of antiviral drugs in dealing with a pandemic is being debated in the medical community due to established drug resistance by the virus. Public health officials at the federal, state, and local government levels are planning for community wide containment and control measures such as group quarantine, work quarantine, community-wide infection control measures and social distancing practices such as "snow days", self-shielding and closures of schools, public transportation, office buildings.

Additionally, the business community is being asked to develop "continuity of operations" plans for its critical services in the face of a severe pandemic. One example of a critical infrastructure issue is the key concern of clean drinking water. The use of chlorine and the disinfection of water, as well as other critical chemicals in our society, will be as vitally important as ever during the course of a pandemic. But the question remains: How will chlorine and other critical products be transported and put into operation with key skilled personnel unavailable?

To this end, the federal government is asking the U.S. business community to begin the planning process to protect employees and maintain operations during a pandemic. Keeping the systems up-and-running that keep the nation up-and-running will be a matter of life and death for many, whether infected with the virus or not. Attached is a letter from the Secretaries of Homeland Security, Health and Human Services, and Commerce asking for help in the critical matter (Attachment 1). Also, attached is a downloadable checklist designed for use by the business community to get started in the planning and response process (Attachment 2 - PDF).

We can't stop the inevitability of a pandemic. History has proven this time and again. However, we can do what other generations have not been able to do as well as we can today: Prepare. It is our best, and in a larger sense, our only true defense.

Water Quality & Health articles are published periodically by the Water Quality & Health Council, an independent, multidisciplinary group that promotes science based practices and policies to enhance water quality and health by advising industry, health professionals, policy makers and the public.