Can Animals Catch the Flu?

By Rachel Stockton rachels at foodconsumer dot org

According to mentalhealth.net, the flu, through the years, has infected many animals, such as ducks, chickens, pigs, whales, horses and seals.

For the most part, humans do not get infected through most animals infected with the virus; however, there are two viruses that are the exception to this rule: the avian and swine flu viruses.

Avian Flu

Recently, it's been reported that there is an avian flu epidemic among the bird population in Asia. 100 people have contracted the illness as a result. How does an avian flu pass from birds to humans? Historically, scientists have concurred that bird flu makes a direct pass through droppings. However, another way the bird flu can infect a human is by going through an "intermediate host"; i.e. a pig.

In 1968, the Hong Kong flu pandemic was the result of the swine flu passing from herds to humans. In this case, the flu that infected humans was not of avian origin. In 1976, a soldier at Fort Dix reported flu-like symptoms one day, and then he expired the next day. Four other soldiers became infected, and were hospitalized. Doctors were afraid that the virus the soldiers carried was the same as the one prevalent during the Spanish flu pandemic of 1918. This was a scary proposition; the Spanish flu claimed 50 million people, world wide.

That virus entered the United States through World War I soldiers returning from Europe; the first report of the Spanish flu came in March of 1918 at Fort Riley, KS. Up until a few years ago, researchers assumed that one reason the virus showed up at the fort was because the military raised swine for the military at that location. It was thought that the swine, who can easily pass the virus to humans, were expediting the spread of the disease.

New Spanish Flu Research

However, new information regarding the Spanish flu virus has shown that no intermediary was needed; this unusual, viral anomaly passed directly from birds to humans at one point. Researchers believe that at some point, the virus mutated into a form that transmitted easily from human to human. This could easily happen, scientists say, if one person happened to be infected by the bird flu and the human flu at the same time. Conditions in such a case would be right for the bird flu and the human flu to mutate into something devastatingly lethal.

In the late 1990s, the Chief of the Medical Pathology Department of the Armed Forces Institute of Pathology (established by Abraham Lincoln) announced that scientists were going to "resurrect" the Spanish flu for further study.

Certainly, this was a controversial move; there was the risk that the virus would "escape" the confines of the lab, either accidentally or through deliberate release (many scientists believe that the Spanish Flu would be a "perfect" biological weapon for terrorism because of its extreme virulence).

However, they were given the go ahead, and tissue from the lungs of two, frozen World War I soldiers who succumbed to the illness was examined: the virus was perfectly preserved. Through the research headed by Dr. Taunenberger, it was discovered that this particular virus began as an avian borne illness; hence, what was previously known about the Spanish flu had been somewhat inaccurate. Up until that time, it had been assumed that like the epidemics of 1957 and 1968, the Spanish flu had originated in swine.

By clearing up some of the fog surrounding the Spanish flu, scientists hope that with further research, a viable vaccine and/or manipulation of the virus itself (by substituting a human virus into the avian flu chain) will lead to breakthroughs that will circumvent much of the devastation of the Spanish flu, should a similar pandemic occur.