By Cory Phare
A deadly disease ravages rural populations in a swath of South America extending through Ecuador, northern Peru, and southern Colombia: Carrión’s disease, a little-researched bacterial ailment also known as Peruvian warts that is spread by sand flies.
It has a mortality rate of 40% to 80%, yet the thin blood smear test that could help curb its spread is an imperfect science at best because of its low-sensitivity and similarity to other tropical infections such as dengue.
Now, Metropolitan State University of Denver biology student Andrew Smith is developing a DNA biosensor that could scale into a rapid and affordable test for the rare tropical disease. His work has caught the attention of the Clinton Global Initiative University, which has invited him to Edinburgh, Scotland, next month to discuss his work.
“Carrión’s disease is disastrously understudied,” Smith said. “Other tests are more efficacious, but you can’t exactly cart a $10,000 lab machine out to remote areas of the jungle.”
The development of a field-portable unit to take to a small Andean town in order to provide directly actionable data to that community would be transformative, said Andrew Bonham, Ph.D., professor and chair of the University’s Department of Chemistry.
“Instead of having to wait a week for a costly lab assay, we want to give folks who are suffering some clarity on what’s going on – if their water is safe to drink and how they can treat the disease,” he said.
Though Carrión’s is considered a neglected tropical disease, the underlying diagnostic approach that may hold the answer is likely familiar to the millions of Americans living with diabetes: a blood-glucose meter.
“It’s simple enough to take home and get health insight within minutes,” Bonham said. “One big interest in our work is taking medicine out of specialized labs and making it available at the point of care in rural populations.”
Smith’s desire to improve access to usable field technology led him to begin developing a DNA biosensor for rapid and affordable detection of the rare tropical disease. This involves developing a single-stranded molecule known as an aptamer to bind to the Pap31 protein and subsequently use in a detection method that can be easily deployed on the ground.
He anticipates that the process will lead to a drastic improvement of testing effectiveness from the current sensitivity of 24% to 36% and hopes to carry out field deployment in Jaén in Peru’s Cajamarca province, working alongside regional nongovernmental organizations and hospitals.
Smith noted that focusing on a smaller-scale disease presents the ability to have an immediate effect.
“There’s a lot of diseases that could use better diagnostics, but this is an area that has a huge gap of knowledge,” he said. “I could work (on something like) Ebola, which is important, but it is unlikely it would have as big of an impact on those suffering, whereas with Carrión’s disease this could really lead to direct help for those affected individuals.”
With lack of established research, that sometimes means taking matters into one’s own hands. Since there hadn’t been an aptamer for the Pap31 protein developed, the logical next step for Smith – with a “show must go on” mindset evidenced by his theatre minor – was to build a biosensor from scratch.
This do-it-yourself ethos is one that Bonham’s lab at MSU Denver cultivates, evident by the multiple papers its users have published on assembling cheap and robust medical devices to reach those underserved populations downstream from more well-resourced innovation hubs.
“A big goal is going from a closed community relying on huge labs to something that most people can order and assemble on their own,” Bonham said. “No one should have a monopoly on this stuff.”
Smith’s presentation in April at the Clinton Global Initiative University won’t be his first international foray. The Honors Program student, who’s planning his application to joint M.D./Ph.D. programs, interned with the U.S. Embassy in Buenos Aires, Argentina, through the Virtual Student Foreign Service Program to study Argentinian voting patterns and connection to the United Nations.
“We’re not making awesome students here; we’re giving awesome students the opportunity to become trailblazers their field,” Bonham said.
If everything goes according to plan, Smith hopes to have a functional biosensor developed by the end of the spring semester to begin testing over the summer. Clinical samples, publishing and working with the Peruvian equivalent of the U.S. Food and Drug Administration would all subsequently follow.
It’s a long way from MSU Denver’s Bonham Laboratory, where Smith is conducting his research, a notable feat for an undergraduate student and one he specifically credited as a distinct advantage.
“Here I get to make a real contribution to science, doing the exact work that scientists do,” he said. “If I was at (a large research institution), I’d just be washing glassware.”
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