Spinning a cytokine storm: the likelihood of an avian flu pandemic is the subject of raging expert debate. Alarmists claim corporate America isn't doing enough to protect itself. Skeptics point to interests vested in whipping up hysteria. Either way, we have "been warned," says Michael Leavitt, secretary of the U.S. Department of Health and Human Services

Risk & Insurance, April 15, 2006 by Patricia Vowinkel

Antivirals like Tamiflu may help lessen the severity of the disease, but it is not clear just how well Tamiflu will work on the mutant strain. And even so, there might not be enough to go around.

The WHO has been discussing a strategy to try to contain an outbreak of H5N1 among people by using a "fire blanket" of antiviral drugs given to everyone in the area around an infection outbreak.

Experts don't know whether the H5N1 virus will be the one to set off the next influenza pandemic.

"The reality is this (pandemic) will happen at some point in time," Leavitt says. "We don't know if the H5N1 virus will be, in fact, the spark that creates the next global pandemic.

"But we are a generation that has, in fact, been warned."

The Six Phases of an Influenza Pandemic:

We are in phase 3 and may be on the cusp of phase 4, according to the World Health Organization.

Phase 1:

No new influenza virus subtypes have been detected in humans. An influenza virus subtype that has caused human infection may be present in animals. If present in animals, the risk of human infection or disease is considered to be low.

Phase 2:

No new influenza virus subtypes have been detected in humans. However, a circulating animal influenza virus subtype poses a substantial risk of human disease.

Phase 3:

Human infection(s) with a new subtype but no human-to-human spread, or at most rare instances of spread to a close contact.

Phase 4;

Small cluster(s) with limited human-to-human transmission, but spread is highly localized, suggesting that the virus is not well-adapted to humans.

Phase 5:

Larger cluster(s), but human-to-human spread is still localized, suggesting that the virus is becoming increasingly better adapted to humans but may not yet be fully transmissible (substantial pandemic risk).

Phase 6:

Pandemic: increased and sustained transmission in general population.

Source: World Health Organization

Pandemics of the
Recent Past

1732-1733  Range: 10 to 49
           years between
1781-1782  pandemics.
           Average: 24
1800-1802  years

1830-1833  The 1918-1919
           pandemic
1847-1848  was severe.
           There were an
1857-1858  estimated 50
           million to 100
1889-1890  million deaths
           worldwide.
1918-1919
           The 1830-1833
1957-1958  pandemic
           also was "very
1968-1969  severe."

Source: Center for Infectious Disease
Research and Policy

Pandemics of the Distant Past

* In 430 B.C., a pandemic struck the city of Athens, killing 25 percent of its people.

* In the 14th century, Europe was hit with the Black Death. About 25 million across Europe died.

* In 1580, a pandemic started in Asia and spread to Africa, Europe and the Americas. In six weeks it afflicted most of Europe. Mortality surged. As many as 9,000 of Rome's 80,000 residents died. Some Spanish cities were described as nearly entirely depopulated by it.

Source: Center for Infectious Disease Research and Policy

PATRICIA VOWINKEL lives in New Jersey. She can be reached at riskletters@lrp.com.