Bird Flu Update
Pandemic Influenza Still a Threat

A city is swept by an epidemic. Thousands are dead, the streets are silent, and all stores, schools, churches, and public places are closed. There are no pedestrians, no cars, no buses, and no trains. The supply of coffins is exhausted. So many have died that the dead must be buried in mass graves dug with steam shovels.

Science fiction? No. This scenario occurred in virtually every large American city during the 1918 influenza pandemic. It was the worst epidemic in human history and killed over 50 million people worldwide. Experts are certain that another influenza pandemic will occur, but when the pandemic will occur, how severe it will be, and what the responsible influenza virus strain will be are unknown.
 

Influenza is a viral infection which involves the nasal passages, throat, airways, and sometimes lungs. Symptoms in uncomplicated cases include headache, fever, chills, muscle aches, cough, and sore throat. The virus is transmitted from person to person and can cause serious or even fatal infections, usually pneumonia, especially in the very young, the very old, and in people with underlying medical problems.

Epidemics and Pandemics

Influenza causes yearly epidemics. An epidemic is an outbreak limited to a particular city, area, or region. Flu epidemics occur between October and March in the Northern hemisphere, in the summer in the Southern hemisphere, and throughout the year in tropical areas. Currently, our yearly influenza epidemic is in full swing.

A worldwide epidemic or outbreak is called a pandemic. Influenza pandemics occur roughly every 10 to 15 years, and pandemic influenza is often severe with high death rates. In the 20th century, influenza pandemics have occurred in 1918, 1957, and 1968, although the 1957 and 1968 pandemics were not as severe as the 1918 pandemic. Pandemic influenza can start in the summer in the Northern Hemisphere.

Will H5N1 Cause The Next Pandemic?

Avian influenza (H5N1) is considered a candidate to become the next pandemic influenza strain. However, in order to cause a pandemic, a flu strain must be transmitted easily from person to person. H5N1 has been transmitted between humans only rarely. In a few clusters of human infection, the virus was first acquired from chickens by a human, and then transmitted to other humans. If the H5N1 virus changed so as to be readily transmissible between humans, that strain could cause a pandemic.

The Deadly 1918 Flu Virus Was a Type of "Bird Flu"

An interesting discovery came from research on the 1918 pandemic flu virus. Working with fragments of preserved lung tissue from patients who died in 1918 of influenza, scientists have recreated and analyzed the original deadly 1918 virus. The scientists found that the 1918 virus was, like H5N1, an avian virus which became adapted to humans. This discovery and occasional human to human transmission of H5N1 suggest that H5N1 may be the virus which causes the next influenza pandemic.

Preparations for Pandemic Influenza

Government and public health authorities are preparing now for the next flu pandemic, although no one can predict its timing and severity. Public emergency plans are being readied. Several H5N1 vaccines have been developed. Governments and even some individuals are stockpiling influenza drugs. Even so, in the event of a flu pandemic, there may be shortages of vaccines, drugs, and other resources. For example, if a flu pandemic were to occur now, the number of people with pneumonia and respiratory failure who require a ventilator for survival would exceed the number of available ventilators. This would require some difficult and unpleasant rationing decisions. Hopefully, research and adequate preparation will give us many advantages when we next confront one of mankind's most dangerous natural enemies.