Assistant Professor Viveka Vadyvaloo holds a jar containing a colony of fleas. The insects look unsuspecting, but they're helping her understand one of the deadliest diseases in human history.
The bubonic plague was responsible for tens of millions of deaths in Europe and Asia during the 14th century. It became known as the Black Death.
The plague spread to humans on a massive scale from flea bites. It caused a blockage in the fleas’ system, forcing them to regurgitate bacteria into their human hosts, Vadyvaloo said.
Vadyvaloo uses a modified organism that cannot cause the disease, but allows her to make safe modifications to the organism while searching for genes that code for proteins, which that could be helpful in controlling the disease-causing agent.
Ultimately, Vadyvaloo said she hopes to prevent the spread of the disease altogether.
She witnessed the complications of infectious diseases all the time while growing up in South Africa. She found her way into a life of research after earning her degree in microbiology and biochemistry, and decided she wanted to do something that would make a lasting difference in the world, she said.
While all diseases fascinate Vadyvaloo, bubonic plague really caught her attention.
“It has this dynamic,” she said. “It is a really old disease, but we still don’t know so much about it.”
The plague can jump from one species to another, but which species it can infect and why remains a mystery.
The disease also hibernates for certain periods before becoming active again: No one knows why, Vadyvaloo said.
It wasn’t until 1914 that scientists learned the plague came from fleas. Last November, researchers finally confirmed a species of bacteria called Yersinia Pestis causes the disease.
While the plague had its most successful run centuries ago, the disease is a long way from dying off, Vadyvaloo said.
“This is not a nonexistent issue,” she said.
African nations, especially Madagascar, still face a serious threat from the disease, as many of the island nation’s residents depend on animals that may live in a non-sterile environment, Vadyvaloo said.
But the plague has a tendency to strike closer to home in the U.S. as well, she said. A 7-year-old in Colorado contracted the disease from a squirrel last week, and a man in Oregon recently picked it up from his cat.
Vadyvaloo’s research is funded by the National Institute of Health. Due to events such as Japan’s use of the plague as a biological weapon during the Second Sino-Japanese War, the U.S. has an investment in the research.
“The U.S. is interested in the plague because of its potential for ‘bio-weaponization',” she said.
Vadyvaloo knows her chances are slim for achieving her ultimate goal of completely thwarting the spread of the disease, but she continues to work against the odds.
“I’d like to understand the molecular basis for how this disease transmits,” Vadyvaloo said. “But most scientists never achieve their goals in a lifetime. You just hope to contribute.”
Correction, Sept. 18, 2012 at 1:34 p.m.: The photo with this story was not captioned correctly. The fleas in the jar were not infected with anythin, nor do they develop the disease. The photo was aken in a laboratory in the Animal Disease Biotechnology Facility, not the Paul G. Allen Center for Global Animal Health.
In a previous version of this article, the nature of Vadyvaloo's reseach was incorrect. WSU does not have the Yersinia Pesis bacteria. Rather, Vadyvaloo uses a modified organism that cannot cause the disease, but allows her to make safe modifications to the organism while searching for genes that code for proteins, which that could be helpful in controlling the disease-causing agent.
