Secrets of the Dead

Killer Flu Scientists struggle to understand a global killer
Edited for Applause Online by Mary Eileen O'Connor

The outbreak of SARS around the world in the past several years, a particularly nasty flu season this year in the United States, and the recent discovery of a strain of avian flu in a flock of chickens here in the Delaware Valley have no doubt left many people wondering what steps are being taken to protect them from the deadly affects of these diseases.

The new program Secrets of the Dead "Killer Flu," airing Wednesday, March 3 at 8 p.m. on WHYY TV12, follows scientists who are struggling to understand the causes of the 1918 influenza epidemic -- which claimed the lives of an estimated 40 million people worldwide and 13,000 in Philadelphia alone -- and examines how their discoveries hold the key to unlocking the mysteries surrounding diseases that currently pose a threat to the global population.

Dr. Jeffrey Taubenberger, one of the pathologists featured prominently in the program, is chief of the division of molecular pathology at the Armed Forces Institute of Pathology. In the film, he speaks at length about the work he's done trying to break the genetic code of the 1918 influenza virus in an effort to better understand what made it so lethal, and what we can do to prevent a similar pandemic. Below, Dr. Taubenberger provides additional perspective on this dreaded virus.

Q: What are some of the biggest misconceptions about the flu?
A: The first is that it's not a serious disease. It's thought of more as a nuisance than a serious problem. It's not a fantasy threat. The second is that the term "flu" is used quite widely to describe a number of both respiratory and intestinal problems - medically, "the flu" refers to a specific infection.

Q: How much should we worry about the use of a potent influenza strain in a terrorist attack?
A: I think the likelihood of a terrorist group using the flu is very small. The flu is generally just not nearly as deadly as some of the other agents you've heard about - anthrax, smallpox. It would not be an effective weapon.

Q: How is the flu vaccine developed, and why have we been told that even with the flu vaccine, we may still get the flu this year?
A: The World Health Organization (WHO) has a surveillance network of doctors around the world who take cultures on any patient they see with flu-like symptoms. If the cultures come back positive for the flu, they are forwarded to bigger centers like the Centers for Disease Control.

These centers compare data with one another and, twice a year, make recommendations about which strains should be included in the vaccine for the coming year. This year, however, the virus mutated after the vaccine was distributed. The vaccine will still offer some protection though. What you'd likely get is an infection that's not as severe.

Q: It's believed that birds are at least partly responsible for bringing the flu to humans. Are we on the verge of another pandemic given the recent outbreak of avian flu in Asia?
A: It's possible that a pandemic will never occur again, but I think that's unlikely. The big worry with the avian flu is that a "mixing" might occur. If one of the victims got the human flu and the avian flu at the same time, that could theoretically create a third, new strain that could spread to pandemic levels. In 1918, it should be noted though, there were no antibiotics. So a lot of people died from secondary infections that couldn't be treated at the time but now could be.

Q: So what can we do to prevent another pandemic?
A: We have to appreciate the risk. Our best defense is surveillance of the ways that the flu in birds and other animals gets into people. We need to catch things before they're adapted to humans. Surveillance would enable scientists to identify dangerous strains and make a vaccine against them before they were well-circulated. One novel idea that people are working on is to make vaccines against all the known types of bird flu that are out there, so if one of those were to appear, you'd have a huge head start. We're not there yet, but it's a start.

Q: What will decoding the DNA of the 1918 flu strain ultimately mean for us?
A: The bottom line is that the way influenza viruses move around between species clearly has some very important implications for us, both in the realm of public health and in agriculture, because the cost of influenza to poultry and swine farms is very high...If we can learn where the virus came from, how it got into humans from birds or pigs, or why it was so nasty, we can look to the future.

As we plan the vaccine, maybe we should do surveillance not just of humans but of animals. Maybe there are particular genetic changes that we can associate with the 1918 flu that would be linked to virulent behavior - we could screen for those. Let's say there was a particular mutation in the 1918 strain that could be shown conclusively to cause this kind of behavior, we could not only screen for it but could design a drug target against it. Ultimately, we hope that eventually, there will be many general applications, and it won't be a case of just going back and trying to solve a mystery of something that has no relevance to today.