A research team co-led by professor Dr. Sunil Parikh, MD, MPH, has received $500,000 in funding from the Bill & Melinda Gates Foundation to continue to develop an innovative noninvasive test for malaria using lasers and ultrasound.
The grant will allow researchers to build two improved prototypes of their cytophone testing platform and to do extensive field testing in the West African nation of Burkina Faso, where malaria is endemic, said Parikh, an associate professor of epidemiology (microbial diseases) at Yale School of Public Health and infectious diseases at Yale School of Medicine. Parikh, a co-principal investigator on the project, studies malaria interventions in Africa.
“The goal is to get at both the sensitivity and the specificity of this device,” Parikh said. “I think this grant is going to help us move the research to the next phase.”
Malaria is an enormous health problem globally. In 2021, the most recent year for which data is available, nearly half of the world’s population lived in an area where malaria is endemic, according to the World Health Organization. There were an estimated 247 million malaria cases that year, an increase of two million compared with 2020, and 619,000 deaths, according to the WHO. Young children, pregnant women, and nonimmune travelers are the most vulnerable to severe infection.
Parikh’s co-principal investigator is Professor Vladimir Zharov, director of the Arkansas Nanomedicine Center at the University of Arkansas for Medical Sciences (UAMS) and co-founder of CytoAstra, a UAMS spinoff company advancing cytophone research. CytoAstra is a sub-award recipient of the Gates Foundation grant. Zharov pioneers noninvasive technologies for medical applications including detecting circulating melanoma cells noninvasively using what was a large, nonportable early prototype of the cytophone platform. Realizing the platform’s potential application for human malaria, Zharov worked with Parikh to develop a portable prototype that could detect malaria infection in people living in endemic settings.
The cytophone technology uses lasers at specific wavelengths focused on superficial blood vessels. When the parasites that cause malaria infection enter red blood cells, they use the hemoglobin inside those cells to liberate amino acids. A byproduct of this process is the release of hemozoin, a compound containing iron. When hit by a laser, hemozoin absorbs more of the laser’s energy than hemoglobin, meaning cells infected with malaria parasites absorb more than noninfected cells. This absorbed energy is transformed into heat, and the heat expansion generates acoustic waves. The cytophone technology detects these waves using a small ultrasound transducer placed on the skin. After software analysis, peaks in the detected acoustic waves can identify malaria infection.
The technology could eventually represent a big improvement in diagnosing, treating, and understanding malaria. Malaria is currently diagnosed by two methods, light microscopy, and rapid antigen blood tests.
A problem is that they aren’t very sensitive. “You can have a very large parasite load with both microscopy and rapid diagnostic tests before you have a positive test,” Parikh said.
Because the cytophone platform can potentially scan a much larger volume of blood, it should be far more sensitive than current tests, Parikh said.