Bird Flu Sheds Light on Lack of Infectious Disease Planning

Since the first three cases of "bird flu" (the H5N1 influenza virus strain) were reported in Vietnam in 2003, substantial resources have been invested to slow its spread. Worldwide attention has been focused on what to do if the virus mutates sufficiently to cause a global pandemic through person-to-person transmission.

The H5N1 virus reaches humans through contact with infected birds, poultry being the most common carriers. To be sure, the growing number of cases and frighteningly high death rate among those stricken is legitimate cause to consider "worst case" scenarios.

The World Health Organization (WHO) notes that there has been no evidence of avian influenza being able to spread beyond someone who acquired the disease through extremely close contact with a person already ill with the virus. "Though rare, instances of limited human-to-human transmission of H5N1 and other avian influenza viruses have occurred in association with outbreaks in poultry and should not be a cause for alarm," notes WHO. "In no instance has the virus spread beyond a first generation of close contacts or caused illness in the general community."

The Chairman of the Medical College of Wisconsin Department of Medicine cautions, though, that the best response to this particular flu may be developed by remembering lessons from "influenza history" and by taking a big picture approach that doesn't take money away from solving public health problems already present on a large scale.

G. Richard Olds, MD, Chairman and Professor of the Medical College of Wisconsin Department of Medicine, is the Linda and John Mellowes Professor of Medicine. He practices at the Froedtert & The Medical College of Wisconsin Internal Medicine Access Clinic.

"The problem with bird flu right now is that the mortality rate in humans of the direct transmission of this disease from a sick bird to a human is about 30% and some say it's as high as 50%. So it's a pretty darn fatal disease," Dr. Olds says. "It also attacks all age groups and it kills people relatively fast. That is very similar to the characteristics of the swine flu epidemic of 1918, the so-called Spanish flu, which had the unique quality of attacking all age groups, having a 30% mortality rate, and killing people in two to three days. That's why a lot of people are scared.

"But the big difference between the Spanish flu epidemic and the bird flu epidemic is that so far there is zero evidence that people can transmit the bird flu widely from person to person. For that to happen this virus has to have a second genetic recombination of some kind, and that will undoubtedly have to take place in a human being that is co-infected with bird flu and co-infected with a normal human influenza virus. How likely is that to occur? I have no idea."

Swine Flu Scare of 1976
Dr. Olds noted that the "swine flu scare" of 1976 resulted in a vaccine response that may have caused more problems than it solved. "We seem to have completely forgotten that in 1975, at the tail end of the flu vaccine season, there were a few cases of an H1N1 swine flu virus," he said. "There was a great scare that the following flu season we would have another pandemic of 1918 swine flu because that was the serotype (a group of closely related microorganisms distinguished by a common set of antigens) of the 1918 flu epidemic and we hadn't seen that serotype for a while.

"So we created an experimental vaccine against the swine flu and in 1976 we mass immunized a lot of people in the United States. Now a couple of bad things happened. One of them was that the experimental vaccine was more toxic than the regular flu vaccine we would normally use and caused some Guillain Barre syndrome (a polyneuritis of unknown cause characterized by muscle weakness and paralysis). That scared people out of using the flu vaccine we use today that does not cause Guillain Barre, and it obviously caused some toxicity in those people because it was given to, quote, 'prevent' an outbreak of swine flu.

"Well, what happened? Nothing happened. We not only didn't have the swine flu epidemic but we ended up with the Russian flu epidemic the following year that was a completely different strain, not the one that we vaccinated people against. People might argue, of course (the swine flu epidemic) didn't occur because we vaccinated everybody, but that is not true.

"Not only did we not vaccinate everybody, but we only vaccinated the people in the United States and Europe. There are plenty of other people on this planet who could have gotten the swine flu, and they didn't. So all that meant was that we were unable to accurately predict a swine flu epidemic in 1976. We did something. It caused some toxicity to the millions of people we vaccinated with that vaccine. Am I saying it was a bad thing to do? No, it wasn't a bad thing to do. But it ought to have been an example to us that we're not so good at predicting what Mother Nature will do. And that was within our own lifetimes."

Better Overall Response Required
"We (the US government) just spent a billion dollars to develop an experimental vaccine against the H5N1 bird flu virus. I don't know that that was a wise expenditure of a billion dollars. And the second plan is to stockpile Tamiflu (brand name for the drug originally marketed by Swiss manufacturer Roche to treat "regular" flu a day or two after symptoms occur). Well, we already know that this bird flu is likely resistant to Tamiflu and it only takes a point mutation to be resistant. It will certainly make the Swiss happy and rich, but I don't know if that's a great plan.

"On the other hand, some of us that are more in the international arena would ask, why don't we take a fraction of the dollars that the government's about to give to big pharmaceutical companies and actually fight bird flu in the Third World countries? We should fight it there before it gets to our shores, but we're actually intentionally waiting for it to get here. The smarter thing is to invest in public health responses, some vaccine perhaps, some anti-virals. But this is a global fight. If we think that any infectious disease will not become our problem, we're wrong. What happens in the rest of the world matters to us; didn't we learn that in the AIDS epidemic?"

"It's not that we shouldn't be concerned about H5N1. I'm concerned. But the fear issue related to a single influenza strain is really unfounded. We're worried about the wrong stuff. We should be focusing on health care in general, focusing on the many public health problems that impact people in our communities today."

Dan Ullrich
HealthLink Contributing Writer

In the September 15 issue the conversation with Dr. Olds will continue, touching on the incidence of avian influenza and the advisability of taking common protective measures.

"Reflections" is a collection of essays by the health professionals of the Medical College of Wisconsin.