A generation ago, people expected infectious diseases to become a public health problem of the past. But today, despite the continual development of antibiotics and vaccines, infectious diseases are the second leading cause of death worldwide.
In addition to a persistent stable of infectious diseases, new and re-emerging diseases continually bombard us. Think SARS, West Nile, E. coli, monkeypox, HIV/AIDS, and multidrug-resistant tuberculosis, to name a few.
This problem is the primary concern of Anthony S. Fauci, MD, director of the National National Institute of Allergy and Infectious Diseases, NIH. Fauci delivered the 20th Harry A. Feldman Lecture on March 24 at the Bloomberg School. His lecture was part of the 78th annual meeting of the American Epidemiology Society held March 24 and 25.
During his presentation, Fauci showed a slide—one he often presents to Congress--of a world map superimposed with the names of all types of infectious diseases and their locations. “Every year, I add one or two more--sometimes three,” he said. “It’s gotten to the point where I need to remove a few just to read the slide.”
What makes infectious diseases so difficult to combat is the extraordinary ability of viruses, bacteria and parasites that cause these diseases to change over time. Moreover, 75 percent of today’s emerging pathogens are zoonotic, meaning that they jump species. Think Avian flu.
Fauci said he could not sum up the problem any better than Nobel Laureate and microbiologist Joshua Lederberg, who said, “The future of humanity and microbes likely will unfold as episodes of a suspense thriller that could be titled Our Wits Versus Their Genes.”
Fauci groups infectious diseases into three categories: emerging (SARS), re-emerging (TB, West Nile) and deliberately re-emerging. The latter are those infectious agents forced upon the world by bioterrorists. Even though more people died of the flu in 2001 than died of anthrax, the fear factor of bioterrorism sparked a big infusion of resources into biodefense. Fauci contends that this funding is still “a boon for public health” overall because the strategies to combat bioterrorism are founded in basic research that can then be used to treat diseases emerging from other sources.
“All can be treated using fundamentals of public health and basic research and science,” he said. “And there are tools in place today that don’t take the place of common sense, but they do help.”
These tools include the rapidly expanding areas of genomics and proteomics, and the new power to sequence of microbes quickly—what used to take a year now takes a day or two. The research world is already seeing results. Last year, the malaria vector and parasite were both sequenced. And just a year after the SARS virus was discovered, the microbe was sequenced, and a vaccine was in development. “The rapidity with which the public health community mobilized to attack this [disease]… I don’t ever recall seeing anything this rapid,” Fauci said.
But even with these tools, it’s still tough to outsmart biology. That’s why Fauci says it’s going to take a combined effort of basic bench science, disease surveillance, and mobilized and coordinated public health forces to keep up with new and re-emerging infections. –Kristi Birch |
