French immunologist Norbert Gualde, M.D., is most interested in the how epidemics influence and are influenced by human society. He supports the concept of immunology of populations, the idea of an ecology of immunity within populations, to explain why some contagions are lethal and some merely annoying. He makes that argument in English in his newly translated book, “Resistance: The Human Struggle Against Infection.”
What is the biggest misconception people have about outbreaks?
“They think that an outbreak is due solely to a microbe—a bacteria, virus or parasite. Things are not so simple. An outbreak, an epidemic, is, as the Greek etymology tells us, the spread of something—be it a microbe or an idea—among the people. A nasty microbe does not spread by itself. It does not walk or fly or swim or whatever. To spread among people, a microbe needs help, and usually it gets that help from humans. That’s why I called one of my chapters ‘Man is the epidemic.’”
What reaction did you get when the book came out in France?
“Often readers are surprised to realize that they are living in a world belonging to microbes. For instance, if you imagine that our world is twelve hours old, the bacterial world appear at the second hour while the human species is just few minutes old. And many readers were astonished by the fact that microbes were on them, inside them and that even their own DNA was crossed with those of microbes.
“We live in a world where microorganisms are numerous and everywhere. These microbes practiced, during billions of years, the adaptation game, which has made them able to survive many cataclysms.”
I didn’t realize that none of these “new diseases,” such as AIDS, ebola, Legionnaire’s disease, even prions, are really new. In your book, you say it’s better to speak of “new diseases” rather than “new germs,” because most if not all pathogens already existed but were buried deep in a forest or among people who had developed resistance to it generations ago.
“These microorganisms are quite old, and they are the gold medal winners of adaptation. The influenza virus, for example, changes its jacket each winter and becomes a little bit different but it is still an influenza virus.
“The menaces will last forever not only because the microbes will but also because of what we are doing to our world: ecological modifications such as global warming and destroying the forests, traveling faster and everywhere while carrying with us all kinds of germs, and the ever-present wars, riots and other kinds of social chaos. Almost 900 million people are starving, which weakens their immune defenses.”
What would we have to do to stem or stop these immunological menaces from coming up so often?
“International organizations such as the World Health Organization (WHO) are quite good at detecting and fighting new infectious diseases. The people working for these institutions do a very good job, but most of the time they track down the diseases while the better way would be to prevent them, to kill them in their nest.
“We have to be careful with ecology, and prevent poverty, ignorance and famine in the world. It is also very important to help organization such as WHO to prevent the spread of new infectious diseases when they emerge.”
In the United States recently, grocery-store spinach turned out to be carrying E. coli bacteria, which killed a few and sickened many. Is it rare that a vegetable is a carrier for these kinds of diseases? Not even vegetarians are safe.
“It has happened before. People have gotten hepatitis because salads sold by a grocery store were washed with water contaminated by the virus. Similarly, an epidemic of typhoid was caused by apples were carrying the bacteria. Microbes are everywhere, so it is not surprising that they are present on vegetables. After all, vegetables also suffer infectious diseases.”
Just after I finished reading your book, I had to fly to a convention in another city for work. I imagined evil microbes ready to attack me in the air in the plane, in the hotel, as I shook so many people’s hands all weekend. Does that ever happen to you? Knowing all you do about infections and epidemics and so on, how do you get through a day in public?
“I am quite confident and comfortable.
“Don’t be surprised by my answer. Microbes and human are the produces of a co-evolution; we’ve been getting along for millennia. Sure, the relationship is sometimes blemished, say, by plague, smallpox, Spanish flu. But if we take the long view, we realize that microbes are so numerous and so diverse and not, most of the time, so nasty.
“When you were in the convention room, listening to interesting speakers, did you realize that in terms of living species you were billions and billions—the humans present in the room and the microbes. Each of us is a living zoo.
“I am a living zoo quite confident of the future. My ancestors, healthy enough to cope with their microbial environment, permitted me to write books and have one published overseas. I was born and raised in Algeria, and I remember my grandparents telling me how many of their relatives—children, brothers, sisters—died of diphtheria, malaria, typhoid and who knows what else. But my ancestors, who lived in primitive conditions, survived.
“Now we have so many more ways to battle the few nasty microbes that I believe we should not be afraid. During the last sixty years we have created many cultural protections, including vaccines, antibiotics, and better sanitation, to stem epidemics. In a certain manner, we can say that at the present time our best immunological organ is our brain.”
What are researchers discovering about human resistance to epidemic diseases?
“People are doing research into why some people do not get sick even though they are in contact with HIV and other viruses in their daily lives. Is it in their genes? We’ve discovered that how well a drug works may sometimes depend upon the genetic background of person we give it to. More research on human immune defense, which we know is very diverse across humankind, could help us discover new drugs or the best way to use already well-known molecules to boost others’ immunity.
“On the microbial level, one big problem is the fact that many highly dangerous bacteria are growing resistant to current antibiotics, which makes them even more menacing. Antibiotherapy, though, is running on almost totally flat tires, and needs more good ideas and money to better fight the new wild beasts. Discoveries about microbe genomes are of the first importance. They could help us understand the germs’ biology and offer new ways to stem their virulence.
“Scientists also are investigating the biology and genetics of vectors (transmitters) such as mosquitoes, which is important to prevent the spread of parasitic diseases such as malaria. And one very important field is the development of new vaccines. For instance, vaccines are now used against diarrheas, diseases that kill thousands of children each year. Tuberculosis needs a new vaccine, and an efficient immunization against malaria would be fantastic.”
We seem to have stopped talking about “eradicating” diseases in favor of “combating” or “managing” them, such as tuberculosis. Will we ever go back to thinking a disease could be eradicated?
“One disease was eradicated: smallpox. The WHO planned to eradicate polio by the end of 2000, but in spite of its efforts the disease still exists, mostly because some political and religious leaders opposed immunization.
“But keep in mind that even if smallpox is eradicated, the virus still exists. It is present not only in laboratories the keep the virus after an international agreement but also in the permafrost where bodies of people who died are present. And it is probably hidden in secret locations, illegally. Smallpox was eradicated after a world campaign of immunization, but now all the people born after 1980 are not immunized, so in terms of immunity of populations that means there is some danger in case of a bio-terrorist attack using the smallpox virus.
“And it’s worth noting that the generation of people born after 1980, while escaping the smallpox terror, now live in a world confronted to a new pandemic, AIDS.
“Eradicating a disease also is not synonymous of eradication of a germ. For instance the highly dangerous H1N1 influenza virus responsible of the Spanish influenza pandemic was “rebuilt” in vitro. What we can do is to trust that that very aggressive agent will never pass the fence of the laboratory were it is kept.”
Do you think we will ever have to re-open sanitariums, much like the sanitariums for tuberculosis patients, for some new or revived disease?
“When AIDS appeared, some leaders in some countries where democracy does not exist were interested in organizing some kinds of “AIDSariums.” Even though I am absolutely convinced that in their time sanitariums (we had many in France) were quite useful and did contribute to the cure of tuberculosis, I do not trust any kind of new ghetto for any kind of person carrying a dangerous germ.
“Obviously in a sort of science-fiction scenario one can imagine the emergence of a super-aggressive germ menacing the human species and to fight that danger we would organize some special wards in hospitals. But I hope that never again will some people have to spend years of their life isolated in huge hospitals. I cross my fingers that we’ll never have any sort of infectious gulag archipelago.”
What are you working on now? What will you write about next?
“I am working on describing the relationships between immunity and societies. Each has a strong influence on the other.”