Avian Flu, the real numbers

You may know the saying: numbers don't lie, but liars are good with numbers. Taken out of context, statistics can be very deceiving. So here are some of the numbers that we were given. Let's try to see what they really mean.

As of today (September 28, 2006), 251 cases and 148 deaths have been reported by the World Health Organization from Avian Influenza since 2003. Most of the cases were found in Vietnam (93), Indonesia (68), Thailand (25), and China (21) with Egypt (14) and Turkey (12) having started to report cases since early 2006.

This initially seems a frightening percentage of deaths per person infected; 59% death rate.

However, you need to know that these figures account only for the cases actually reported. You have to realize that in these countries the access to health services is very limited. People don't have money to pay for medical services and are often scared to go to hospitals and clinics. When they do resort to medical help, it's often too late to do anything, at least through modern medical methods.

So the real figures are probably very different from what is reported. There may be many more people infected with the virus but they get better on their own through resistance. To get the exact numbers we would have to test every person in those countries for antibodies that would show they had recovered from the disease. That option is simply not viable. Not only it would be very costly, but it would only give a picture of the situation at the time of the testing. The data could be obsolete a week later.

The realization that there are likely more human cases than reported has two implications. First, the bird flu may be much more prevalent in those countries than we think; poultry being much more affected than what is believed. There are two potency levels of the avian influenza virus referred to as a low pathogenic strain and a high pathogenic strain. The reason for the small number of avian flu cases reported in birds could be related to the fact that these birds are affected by a low pathogenic strain which doesn't kill them but can infect humans. Being a low pathogenic strain it is also milder in humans and therefore a small number of people actually get to a stage where they require hospital care.

The other implication is that although avian flu may be more prevalent than we think, the transmission from bird to human is still extremely limited. In the above countries a number of conditions exist that are not mirrored in North America:

• A large portion of the families have domesticated poultry particularly in rural areas
• Most the chicken are found in areas where they can intermingle with wild fowl and therefore susceptible to contracting wild avian influenza (remember, the influenza is native in wild fowl; it doesn't affect them)
• There are no widespread measures to test for presence of influenza
• People come in close contact with their poultry on a daily basis

This in principle should lead to a very high rate of avian flu in humans, but the numbers are actually very low. So either people have either been sick and recovered, or they have built an immunity to the virus. Or even more likely - based on research I alluded to previously - the avian flu has a very low transmission potential.

In the end we see that the numbers we are given by the WHO are actually no indication whatsoever of the reality when it comes to the extent of spread of the disease either in birds or in humans.

To continue with the idea of putting numbers in the right context, when these number are taken in comparison to population, the picture gets even more interesting. Let's examine each of the countries indicated above, the number of cases and the total population.

Vietnam: 93 cases/80 900 000 population = 0,115% or 1,15 person per thousand people
Thailand: 25 cases/63 080 000 = 0,04% or 4,0 per ten thousand people
Indonesia: 68 cases/213 720 000 = 0,032% or 3,2 per ten thousand people
Egypt: 14 cases/73 671 000 = 0,019% or 1,9 per ten thousand people
Turkey: 12 cases/70 710 000 = 0,017% or 1,7 per ten thousand people
China: 21 cases/1 266 838 000 = 0,002% 2,0 per one hundred thousand people

If we take an average for these countries, we get one 1,3 person affected for every ten thousand people. Even if this kind of situation would spread worldwide, it would still have a minor impact. I don't know the population where you live, but here in Toronto, Ontario, Canada, we are supposedly about 3 million people. If I take the same average and I apply it to Toronto, I get 0,4 person affected. Less than one person will actually get sick within our population. It actually takes about 8 million people in a City or area before we get one case of infection. To me that's a pretty low rate. This proves again that the Avian Flu is actually very difficult to spread.

So why are the medical authorities so much in an uproar over this.

Stay tuned. More to come on the financial benefits of creating an Avian Flu panic.

Alain Normand

P.S. I'm not being insensitive here. Every life is important and every death is disturbing; 148 deaths are tragic. I am simply trying to put this situation in the proper context. Later on I intend to discuss why the same kind of alarm isn't raised with regards to HIV/Aids. In my mind that is a much more tragic, real, and current pandemic than the Avian Flu. So why isn't the same kind of money allotted to HIV/Aids as what is now being provided towards fighting or preventing Avian Flu? A.N.