University tuberculosis researchers form Russian partnership
Disease's resurgence includes drug-resistant strands, posing large problems abroad
Tuberculosis, a disease usually associated with the turn of the century and the Great Depression, is making a comeback, with drug-resistant strains of TB recently found across multiple countries. Because of the disease’s global reach, researchers from the University will be teaming up with Russian researchers to look at treatment and prevention.
“Everything was going well until the late 80s or early 90s,” Asst. Infectious Diseases Prof. Dr. Scott Heysell said about the disease’s resurfacing. “HIV changed the landscape.”
TB is a bacterial infection which spreads through the lymph nodes and blood stream
to other organs in the body. It can be transmitted through the air, making the disease contagious and easily contracted.
TB bacteria can live in an inactive — or latent — form inside the body and become active when the immune system weakens. People with the inactive form will not show symptoms.
When active, TB bacteria require oxygen to thrive. Because of this, TB usually attacks the lungs, where the oxygen concentration is highest.
The disease has existed in its general form for thousands of years.
“TB has been around for a while — we probably carried it with us from the early days in East Africa with the domestication of cattle,” Heysell said. “It is traced along with human evolution.”
The disease, once widespread and unconstrained, became better controlled by the late 1950s with the help of newly-developed antibiotics.
With the spreading of HIV, however, TB experienced a rebirth, preying on the weakened immune system of HIV patients.
TB is making a strong comeback today, developing new strains with varying degrees of drug-resistance. Many present strains of TB are labeled either as multi-drug resistant or extensively drug-resistant. Heysell’s research confirmed the resistance developed due to inherent qualities in the germ, such as its capacity to replicate and genetic mutations.
Of the 300 average cases of TB in Virginia each year, only five are drug-resistant. However, this is not the case internationally — in Siberia, one hospital will treat more than 1,000 cases of TB, 30 to 50 percent of which are drug resistant, Heysell said.
Currently, Heysell and Dr. Eric Houpt, assistant professor of Internal Medicine and Infectious Diseases, are collaborating with researchers in Irkutsk, Siberia in an effort to develop optimal doses of antibiotics and develop faster ways of testing for TB. The University research team received a grant of $342,598 from the National Institute of Allergy and Infectious Disease to fund its work for the next two years.
Heysell said the relationship with Russia is bi-directional, as both the National Institute of Health and Russian Federation for Basic Research, the Russian equivalent of the NIH, have to approve of all research and interactions.
The Russian researchers specialize in the molecular epidemiology of TB, a weakness for their American counterparts.
“This is very, very difficult to treat,” Heysell said. “… In a well-resourced setting, the cure rates are above 90 to 95 percent for patients with drug-susceptible TB, but in many parts of the world, it drops below 50 percent for drug-resistant tuberculosis, and that’s certainly the case in Irkutsk.”
Despite TB bacteria’s anomalous developments, University researchers remain confident in their work and its potential to lower the mortality rates associated with the disease.