Colorado State University tuberculosis researcher Anne Lenaerts will represent tuberculosis research on World TB Day, March 24, an honor bestowed on only three people in the world. Lenaerts will represent North America for the event, coordinated by the World Health Organization and the Stop TB Partnership. About 2 million people die each year of tuberculosis.
The day is devoted to spreading awareness of the global TB epidemic and those doing innovative work to combat it. Lenaerts has spent her career fighting tuberculosis; she’s currently a key person in the world’s search for tuberculosis drugs and has developed a number of laboratory tests and systems to better and more quickly test the potential of new drugs. Current treatment regimens for TB have not been improved in more than 40 years, and treatments are complex, burdensome and incompatible with some of the most common HIV/AIDs treatments – a disease that often impacts TB patients.
Lenaerts’ work, funded by the National Institute of Health and the National Institute for Allergies and Infectious Diseases at the university’s Mycobacteria Research Laboratories, is described by the Stop TB partnership as being “at the epicenter of the search for new TB drugs.” Her tests for drugs are used by laboratories around the globe, and at CSU, Lenaerts works with a team to test promising compounds sent to CSU from around the world. If their tests show that a compound is effective against TB, the information is passed on to suppliers and pharmaceutical companies. Two compounds Lenaert’s program helped develop are now in clinical trials.
Lenaerts began her career in cancer research, but during a post-doctorial fellowship at the University of Pretoria in South Africa where she witnessed firsthand the ravages of devastation of tuberculosis, she switched her focus.
While formerly thought of as a disease that was all but eradicated in the world, tuberculosis is resurging through the world; in 2008, more than 9 million new cases of TB were diagnosed – a historic high. Tuberculosis continues to infect millions and newer, drug-resistant strains have emerged in recent years to pose a critical problem to global health. Some highly fatal strains of the disease, such as XDR-TB – or extensively drug resistant tuberculosis – continue to emerge and spread but may only be treated with a handful of antibiotics on strict daily schedules stretching for two years. Treatment of some strains of TB cost health systems tens or even hundreds of thousands of dollars per case to treat.
“We must find new drugs – at least three to four new compounds – that are completely effective against drug-resistant strains, including extreme resistant strains,” Lenaerts said. “It’s imperative that those drugs be potent so that we can decrease the treatment time needed – being on antibiotics for two years is difficult for most patients, particularly for those who live in rural, underdeveloped countries where access to drugs is a challenge.
“Drugs are always given in combination – three or four drugs at a time – to try to be effective against a strain that might be resistant and prevent the strain from mutating. Giving a single drug can enable the bacterium that causes tuberculosis to become more easily resistant to that drug. But a mix of drugs means that the patient has a higher chance of experiencing more toxicity, and we also must strive to reduce toxicity while increasing effectiveness and shortening treatment time with each new drug.”
Latent infections and drug-resistant infections must be treated in very different ways. Many cases of tuberculosis, particularly in under-developed countries, are also complicated because the patient has HIV. But the odds of finding a successful treatment even without HIV are not promising; someone without HIV but with XDR tuberculosis has less than one chance in two of finding a drug that will work.
“In the industrial world, many people may be infected with latent tuberculosis, never displaying symptoms but continuing to spread the disease,” Lenaerts said. “In under developed countries, the likelihood that one will develop symptoms and active disease is much higher.”
The bacterium – called Mycobacterium tuberculosis – that causes tuberculosis is difficult to kill. In order to kill it, it must be growing in the host for drugs to impact it, which makes latent cases of tuberculosis extremely difficult to kill. The bacterium also is extremely adaptable to its environment, able to survive in a host or even outside of a host under certain conditions, making TB one of the world’s oldest and most difficult to eradicate plagues.
World TB Day is designed to encourage public awareness of the need to find treatments for tuberculosis, develop funding for research and find new ways to work together globally for a cure. The Stop TB Partnership has developed a global plan for commitment of $1.1 billion for TB research in the United States in 2010, but need public donations to overcome a more than half-billion shortfall in the U.S. and a $2.4 billion shortfall world-wide.
“I think we will be in this fight for a long time. The bacterium that causes tuberculosis has been around for thousands of years. Evidence of it even exists in ancient Egyptian mummies,” Lenaerts said. “After we are all gone, tuberculosis will still be there. It will be sitting in a host, maybe not doing much, but it will survive.”
Lenaerts is one of three women selected from across the globe to represent each region on World TB Day. The other four women selected are also researchers looking for ways to prevent, cure and diagnose tuberculosis. The mycobacterium laboratory that Lenaerts works in at CSU is part of the College of Veterinary Medicine and Biomedical Sciences and the Department of Microbiology, Immunology and Pathology.