It must have seemed like all the furies had been unleashed to torment an already agonized world. The year 1918 saw not only the continuation of the senseless slaughter of World War I, but also the outbreak of an influenza pandemic that killed up to 40 million people worldwide. Scenes that would have been reminiscent of what happened during the Black Death in Europe during the middle ages were occuring daily as thousands of victims, many already weakened by the effects on diet as a result of the war, succumbed to the onslaught.

This is what was occuring in the United States:

The effect of the influenza epidemic was so severe that the average life span in the US was depressed by 10 years. The influenza virus had a profound virulence, with a mortality rate at 2.5% compared to the previous influenza epidemics, which were less than 0.1%. The death rate for 15 to 34-year-olds of influenza and pneumonia were 20 times higher in 1918 than in previous years (Taubenberger). People were struck with illness on the street and died rapid deaths. One anectode shared of 1918 was of four women playing bridge together late into the night. Overnight, three of the women died from influenza (Hoagg). Others told stories of people on their way to work suddenly developing the flu and dying within hours (Henig). One physician writes that patients with seemingly ordinary influenza would rapidly “develop the most viscous type of pneumonia that has ever been seen” and later when cyanosis appeared in the patients, “it is simply a struggle for air until they suffocate,” (Grist, 1979). Another physician recalls that the influenza patients “died struggling to clear their airways of a blood-tinged froth that sometimes gushed from their nose and mouth,” (Starr, 1976). The physicians of the time were helpless against this powerful agent of influenza.

Could this horrifying spectacle be repeated?

The answer is yes, it’s possible. The culprit this time is Avian or Bird Flu. According to the Centers for Disease control. the chances for a Bird Flu pandemic are small – but not impossible.

The H5N1 virus (Bird Flu) does not usually infect humans. In 1997, however, the first case of spread from a bird to a human was seen during an outbreak of bird flu in poultry in Hong Kong. The virus caused severe respiratory illness in 18 people, 6 of whom died. Since that time, there have been other cases of H5N1 infection among humans. Most recently, human cases of H5N1 infection have occurred in Thailand, Vietnam and Cambodia during large H5N1 outbreaks in poultry. The death rate for these reported cases has been about 50 percent. Most of these cases occurred from contact with infected poultry or contaminated surfaces; however, it is thought that a few cases of human-to-human spread of H5N1 have occurred.

So far, spread of H5N1 virus from person to person has been rare and spread has not continued beyond one person. However, because all influenza viruses have the ability to change, scientists are concerned that the H5N1 virus could one day be able to infect humans and spread easily from one person to another. Because these viruses do not commonly infect humans, there is little or no immune protection against them in the human population. If the H5N1 virus were able to infect people and spread easily from person to person, an “influenza pandemic” (worldwide outbreak of disease) could begin. No one can predict when a pandemic might occur. However, experts from around the world are watching the H5N1 situation in Asia very closely and are preparing for the possibility that the virus may begin to spread more easily and widely from person to person

The problem is that flu viruses have a nasty habit of mutating. The reason they mutate is as old as life on the planet; microbes do whatever gives them the upper hand in the fight for species survival. In Jared Diamond’s fascinating Pulitzer Prize winning book Guns, Germs, and Steel, the author lays out a natural history of infectious disease and how those diseases made the jump from animals to humans. Diseases like Measles (cattle), flu (pigs and ducks), Pertussis or whooping cough (pigs and dogs), and smallpox (cattle), made the successful leap in early farming societies because people lived in such close proximity to both the animals and their waste products. Microbes discovered (quite by accident) that humans were just as good a place to reproduce as animals.

Only recently has Bird Flu made the jump from birds to humans. Are we seeing the beginning of a new infectious disease? Here’s the CDC’s take:

Influenza viruses have eight separate gene segments. The segmented genome allows viruses from different species to mix and create a new influenza A virus if viruses from two different species infect the same person or animal. For example, if a pig were infected with a human influenza virus and an avian influenza virus at the same time, the viruses could reassort and produce a new virus that had most of the genes from the human virus, but a hemagglutinin and/or neuraminidase from the avian virus. The resulting new virus might then be able to infect humans and spread from person to person, but it would have surface proteins (hemagglutinin and/or neuraminidase) not previously seen in influenza viruses that infect humans.

This type of major change in the influenza A viruses is known as antigenic shift. Antigenic shift results when a new influenza A subtype to which most people have little or no immune protection infects humans. If this new virus causes illness in people and can be transmitted easily from person to person, an influenza pandemic can occur.

It also is possible that the process of reassortment could occur in a human. For example, a person could be infected with avian influenza and a human strain of influenza at the same time. These viruses could reassort to create a new virus that had a hemagglutinin from the avian virus and other genes from the human virus. Theoretically, influenza A viruses with a hemagglutinin against which humans have little or no immunity that have reassorted with a human influenza virus are more likely to result in sustained human-to-human transmission and pandemic influenza. Thus, careful evaluation of influenza viruses recovered from humans who are infected with avian influenza is very important to identify reassortment if it occurs.

This is what’s giving the folks at CDC nightmares. If Bird Flu were to mutate into a strain that could easily be spread by casual contact among humans, it could wreak havoc on the world’s population and the economy. Why the economy? Here’s a look into a possible future where a Bird Flu pandemic is already a reality in the United States. It’s from a mythical blogger: (Hat Tip: Instapundit)

The United States is battened down before the storm. The government has outlawed all gatherings in public places. In past pandemics that never worked. But epidemiologists say that if we do it early on, it might slow the spread. Modelling also suggests that closing schools and universities is especially important as teenagers and young adults are among the worst hit. We just need to stop them from hanging out elsewhere. Stay at home, is the message blaring from every TV screen.

On CNN it’s now round-the-clock coverage, with a red ‘Pandemic’ banner running across the bottom of the screen. “We’re in the twenty-first century, and they’re telling us about how to wash our hands properly, and practise ‘respiratory etiquette’,” exclaims Jonathan. “Why aren’t there drugs? And I can’t believe there’s no vaccine. This can’t be happening in America.”

Can you imagine the effects on the economy if the government banned public gatherings? Malls would have to shut down. Millions of people would lose their jobs. Tens of thousands of businesses would go under. And that’s just the malls. What about air travel? What about the hospitality, travel, and tourism industries?

The ripple effects would plunge the world into the deepest depression since the 1930’s. We’d be a decade recovering.

Just as a side note, this same scenario would play out if we came under a serious biological terrorist attack. And you might have been wondering what would be so serious about a biological as opposed to nuclear attack by terrorists?

I leave you with with a post from our mythical blogger from the future at the heighth of the pandemic here in the United States:

I watch the scenes of a society descending into chaos from the relative security of my mother’s isolated home. Red tail lights snake to the horizon as people pour out of the cities. Half the doctors haven’t turned up for work; many are either ill, or caring for loved ones.

Who should get the few mechanical respirators that can mean the difference between life and death? The youngest, or those with the best chances of pulling through? “Our leadership must be prepared to make calculated decisions that will force raw prioritization of life-saving resources,” explains a colonel on CNN.

Be afraid? Maybe not. But when Drudge has those stories on Bird Flu I’m going to read each and every one from now on.