Avian Flu - Only a Matter of Time

It's inevitable.
        
That's what health experts say about the chances of Avian Influenza – commonly known as bird flu – coming to the United States.

"Over the past 300 years, ten influenza pandemics have occurred among humans," said Dr. Hubert Peterson, Cimarron Pathology. "Pandemics occur approximately every 30 years. We have not had one since 1969. We are long overdue."

A pandemic, or global epidemic, is an outbreak of an infectious disease that affects people or animals over an extensive geographical area.

So what is Avian influenza?

"It is a type of influenza that is virulent in birds," Peterson said. "It was first identified in Italy in the early 1900s and is now known to exist worldwide. Avian influenza may be transmitted to humans in two main ways: directly from birds or from avian virus-contaminated environments to people and through an intermediate host, such as a pig."

The virus can be transferred to humans through means such as drinking raw blood from ducks – considered in some places to be a delicacy, families eating and selling sick ducks, chickens or other birds and unsanitary conditions in processing.

Influenza can be separated into three different "types" – A, B and C, according to Peterson.

"Type A can infect people, birds, pigs, horses, seals, whales and other animals," he said. "Wild birds are the natural hosts for these viruses."

Type A is also divided into subtypes based on two proteins on the surface of the virus.

"Type B is normally found only in humans," Peterson said. "It has not been classified according to subtype. And, although B viruses can cause human epidemics, they have not caused pandemics."

Type C influenza causes mild illnesses in humans.

"Type C does not cause epidemics or pandemics," Peterson said. "And, it has not been classified according to subtype."

What are the symptoms of Avian influenza?

"Reported symptoms range from typical flu-like symptoms such as a fever, cough, sore throat and muscle aches to eye infections, viral pneumonia, and other severe and life-threatening complications," Peterson said.

One particular strain of influenza virus is of concern, known as H5N1.

"It mutates rapidly and has a history of being able to acquire genes from viruses infecting other animal species including tigers, cats – thus refining its genes," Peterson said. "It has caused severe disease in humans. Lab studies demonstrate isolates from H5N1 have high pathogenicity in humans."

It is this strain of influenza that has health officials concerned a repeat pandemic, such as that seen in 1918 may occur.

In 1918, the Spanish Flu affected an estimated 150 to 300 million people, with 50 to 100 million dying. Experts estimate that, if that is the case given the current world population, an estimated 1.7 million deaths could occur in the United States, with 180 to 360 million occurring globally.

So what is the answer?

"To lessen the possible outcome," Peterson said. "We must formulate a response strategy, which most definitely needs to be a coordinated effort between the private and public sectors."