A researcher in the Department of Microbiology and Immunology at East Carolina University’s Brody School of Medicine has received a grant from the National Institutes of Health to study the pathogen responsible for Lyme disease.
Associate professor Dr. MD Motaleb was awarded $423,000 over two years to investigate the disease mechanisms around the bacterium Borrelia burgdorferi, which causes the multi-systemic disorder known as Lyme disease – transmitted to humans via bites from infected deer ticks.
“The significance of Lyme disease is that a lot of the time it goes undiagnosed because of its flu-like symptoms,” Motaleb said. “And although it is rarely fatal, it has highly debilitating effects in humans. Once it progresses to late disease, it can send people into total unproductivity.”
Lyme disease is the most prevalent arthropod-borne infectious disease in the U.S., with approximately 300,000 cases diagnosed each year, although the disease is largely underreported, Motaleb said.
Three to 30 days following a bite from an infected tick, many people develop a fever and flu-like symptoms, including chills, fatigue, headache, muscle and joint aches and swollen lymph nodes. During the first month, between 60 and 70 percent of patients will develop a skin rash. At this early stage in the disease, antibiotics can be an effective treatment.
“But at one month, up to 40 percent of patients still don’t have a rash,” Motaleb said. “Those are in a bad position. If left untreated, a patient can develop painful swelling in large joints, a stiff neck, partial facial paralysis, heart palpitations, shooting pains, numbness and problems with short-term memory.
“After months or years with no treatment, many patients may be nonfunctional,” he said. “Even if they begin treatment at this stage, disease symptoms may persist years after the antibiotic treatment.”
According to the Centers for Disease Control, approximately 33 percent of untreated patients in the U.S. develop Lyme arthritis. More than 10 percent of these patients become treatment-resistant for unknown reasons, and up to 10 percent eventually experience mild to severe interference with heart function.
Currently there is no vaccine to prevent Lyme disease, but Motaleb hopes his team’s research will eventually lead to the development of a novel pharmacological agent that can prevent - and better treat - the disease caused by Borrelia burgdorferi.
In the meantime, his immediate goal is to investigate the role this bacterium’s movement mechanisms play in the infection of – and disease progression within – a host, as well as the transmission of the pathogen between hosts.
“This organism has a wave-like shape and a unique ability to twist, which gives it a distinctive swimming motion,” said Motaleb. “This ability also makes it extremely invasive – enabling it to swim in highly viscous, gel-like environments such as joints, connective tissues and the brain – where most bacteria slow down or stop swimming altogether.”
Researchers have known for some time that this locomotion is critical to the development and spread of Lyme disease, but Motaleb’s team seeks to discover how to disrupt the mechanism in order to block bacterial dissemination and thus prevent the spread of the disease.
Since Motaleb joined ECU in 2008, he has been awarded more than $3.1 million by the NIH to study Lyme disease.
Other participants on his current grant are doctoral students Kihwan Moon and Matthew Addington-Hall and research specialist Akarsh Manne.