Our Projects

Rocky Mountain Spotted Fever (RMSF)

Rickettsia rickettsi

Rocky Mountain spotted fever (RMSF) is a severe tick-borne disease that is caused by the bacterium Rickettsia rickettsii. This bacterium is transmitted by tick bite, which then targets blood vessels within the body, causing disease. Symptoms include high fever, headache, rash (typically on the palms and soles), and can progress to organ failure and death. Doxycycline is effective in treating RMSF but only if administered early on in infection. Case fatality rates range from approximately 1 to 10% in the U.S., but just across the border in northern Mexico, fatality rates are significantly higher, ranging from 15 to 50% depending on the study and context. We are interested in understanding these drivers of fatality in northern Mexico, studying the pathogen, host, and vector factors related to severity and death.

Encephalitis, commonly defined as inflammation of brain tissue, can be caused by an array of pathogens, autoimmune diseases, and traumatic brain injury. Symptoms center around central nervous system dysfunction (i.e., altered mental status, seizures, confusion, etc.), and it is often difficult to accurately diagnose the true etiology. Vaccines exist for select infectious agents, but preventive measures remain limited. West Nile virus (WNV) is the leading mosquito-borne illness in the US and a major cause of viral encephalitis. While most WNV infections are asymptomatic or mild, about 1 in 150 cases progress to West Nile neuroinvasive disease (WNND), a severe encephalitic condition that is fatal in roughly 10% of cases. Currently, no treatment options exist beyond supportive care. Our research focuses on uncovering mechanisms that drive encephalitis and developing targeted therapeutics to improve patient outcomes.

Chagas Disease -

Trypanosoma cruzi

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi. T. cruzi is sustained in animal reservoirs - including dogs - and is primarily transmitted to humans through triatomine vectors ("kissing bugs"). Chagas disease can lead to heart disease and fatal cardiomyopathy in 30% of those infected; more than 6 million people in the Americas are estimated to be infected, including more than 300,000 people in the United States. Within the Murray Lab, we are working to better define the true burden of disease within the U.S., including the risk of locally-acquired infection throughout the southern U.S. We also have also recently identified evidence of acute vector-borne transmission to humans and a new species of kissing bug in Belize, which had previously been deemed to be in an elimination state. Through building awareness, surveillance, and diagnostics, we aim to lower the burden of disease throughout the region.

In 2020, we launched a national acute febrile illness (AFI) surveillance study with diagnostics for 54 pathogens in Central America. Over 11,000 patients were enrolled in El Salvador and Belize from 2020 to 2024. With an extensive biorepository of samples collected from enrollees, we seek to advance both diagnostic and pathogen discovery. Our goal is to better understand the burden of disease and the progression of infection to inform more effective interventions, including diagnostic and treatment strategies, ultimately reducing the number of outbreaks among vulnerable populations in the future.