Recently, ‘The Independent’ Newspaper had published an article on human deaths arising out of the Bird Flu virus in Egypt. Dr. Vidyasagar, renowned mathematician/scientist, currently at Tata Consulting Services in Hyderabad sent me a well-reasoned response and I have his permission to reproduce that. See below. I was reminded of his response and the article when I saw this news item today about Swine Flu deaths in Mexico City.
Here is his response to ‘The Independent’ article:
This article in the Independent starts by reporting a potentially interesting development in the evolution of the H5N1 virus, also known as the bird flu virus. Unfortunately, it then goes off into wild sensationalism unsupported by science or facts. As a result it is total drivel.
In contrast, a very reasonable and balanced (and highly understandable) discussion of the topic can be found in the Wikipedia at:
The potentially interesting development is that the H5N1 infection is becoming less deadly. This is potentially serious because in earlier instances, those infected died very rapidly before they could infect others. If the infection becomes less deadly then it has greater potential to spread. That point is uncontestable. Implicit in that is the confession that *the existing* mutations of the H5N1 virus can’t spread amongst humans. This fact does not, however, prevent motivated manipulation of ignorant and/or lazy journalists by vested interests. This story is an example of this kind of thing.
What is the basis for the claims of a “bird flu pandemic” cooking in Egypt? There are a princely total of eleven, count them eleven, infections in Egypt. On the basis of this ridiculously tiny sample, various “experts” are trotted out say that (i) the disease is becoming less deadly, (ii) the disease is infecting children and not adults, etc.
The author himself says that bird flu could “turn into the greatest plague to hit Britain since the Black Death,” and speaks of 750,000 Britons dying, not to mention hundreds of millions worldwide. This is sloppy journalism at its worst. The author assumes a 5% mortality rate if and when an outbreak occurs at some unspecified time in the future (perhaps OK), but assumes a 100% *infection rate*! In other words, he assumes that *every single man, woman and child in the world would will become infected* to come up with inflated numbers. This is complete garbage. Even HIV has an infection rate worldwide of less than 1%!
To see what is really happening, we need to understand what the H5N1 virus is, how it infects humans, and how humans can be protected against viruses. The H5N1 virus is just eight different pieces of RNA. It is a parasite and cannot replicate by itself; it needs a host on which it can reside and replicate. So in principle some mutation of the virus could actually replicate and spread in humans. If the mutated virus doesn’t kill the host very rapidly, then in principle more humans could get infected. That is the fear on which the journalists and the vested interests play.
Now let me make another very strong statement. It is not at all difficult to come up with drugs that are very effective against simple organisms like viruses. The real challenge is to come up with drugs that are effective AND SAFE. The overwhelming majority of drug candidates (more than 90%, perhaps more than 95%) fail not because of lack of efficacy, but due to toxicity. Under normal circumstances, all regulatory agencies around the world follow the principle “First, do no harm.” They will not approve any new drug for general use until it has been proven to be safe.
And that is of course absolutely the right thing to do — under normal circumstances. But if for some reason the virus is extraordinarily virulent, the regulatory agencies would put aside all concerns of safety, and rush all sorts of experimental drugs to the market.
How long would it take to find such experimental drugs that are very effective (but, as stated above, not necessarily safe)? Let us use the precedent of the SARS (Severe Acute Respiratory Syndrome) virus that caused so many newspaper headlines in 2003. Though it was supposed to have occurred first in mainland China in November 2002, the syndrome was first identified in February 2003 when a person in Hong Kong died from it. By April 16, the DNA sequence (known as the genome) was already sequenced by various laboratories around the world. By May the operative genes were also identified. Indeed the mechanisms of the SARS virus were well-known by then.
So why weren’t experimental drugs rushed to market to combat the SARS virus? The reason is simple: The SARS “epidemic” was mostly media hype and was not a real epidemic in any sense of the word. Until September 2003, when even the scientific community lost interest in the SARS virus, the total number of reported deaths was 916. Dividing this number by the roughly 180 days from March 2003 to September 2003, this works out to *five deaths per day* around the world. This is hardly an epidemic.
The point therefore is that it took a mere eight weeks for the mechanisms of the SARS virus to be identified, at which time the scientific community was in a position to put out effective (but not necessarily safe) drugs against the SARS virus. How long would it take for the H5N1 virus? The genome (DNA sequence) of the SARS virus consists of more than 30,000 “base pairs” (the symbols A, C, G, T that make up the four constituents of DNA).
In contrast, the H5N1 virus has about 14,000 “base pairs” and a mere eight genes; in other words, the H5N1 virus has a DNA sequence that is roughly half as long as that of the SARS virus. So I would venture to suggest that it will take only a few weeks to find effective (but not necessarily safe) cures for bird flu, should it ever hit humans. At this point the regulatory agencies would have to take a call on whether to permit these experimental drugs to be used for treatment.
If there are only a handful of deaths as in the case of the SARS virus, the regulatory agencies would not permit these experimental treatments. But if we make the wildly fantastic assumption that thousands will die daily (an assumption that ‘The Independent’ correspondent seems to have no difficulty making), then these experimental treatments would surely be rushed to market. Because all the cures would be only experimental, they may have some side effects and thus would not prevent all deaths. However, it takes an extraordinary imagination to predict that “750,000 Britons” would die from bird flu under the right circumstances. The health care community would simply not permit such a thing to happen.
In general, prevention is better than cure, and this is certainly so in the case of viral infections. This means that, once we know what we are up against, we should start constructing effective vaccines against H5N1.
Not all viruses can be combated by vaccines, the HIV virus being a prime example. Given that the H5N1 belongs to the family of influenza viruses, I am optimistic that suitable vaccines can be constructed against any future strain of H5N1 that spreads amongst humans. More to the point, the time to construct vaccines is *after* the virus strain that affects humans becomes known, once we know what we need to defend against, and not now!
Hence I am of the view that efforts to construct and market bird flu vaccines at the present time are premature and of limited utility.
Dr. M. Vidyasagar
Executive Vice President
Tata Consultancy Services
No. 1, Software Units Layout, Madhapur
Hyderabad 500081, INDIA
Tel: +91 40 6667 3001; Fax: +91 40 6667 2222
Update: Worryingly, the plot is thickening.