As a child in Nigeria, the rainy season stands out in Joshua Raji’s memory. The rainy season is mosquito season. With mosquitoes, malaria usually followed.
Raji is very familiar with the brutal life and death cycle — watching people get sick, and some die, year-after-year, from a preventable and curable disease that is transmitted by the tiny insect. An estimated 241 million cases of malaria were reported in 2020 and 627,000 people died of the disease, according to the World Health Organization. African nations accounted for 95 percent of all reported cases and 96 percent of all malaria deaths in 2020, yet the United Nations views malaria as a global concern, singling it out among its Sustainable Development Goals. Raji cannot recall the number of times he battled malaria growing up, just summing it up as several. He believes scientists are close to bringing the mosquito’s reign as the planet’s deadliest animal to an end. He believes this because he is one of the scientists searching for a solution.
Raji graduated with a Ph.D. in biology from FIU in 2019 and is currently a postdoctoral fellow at Johns Hopkins School of Medicine. Just in the early years of his career, Raji is gaining attention for his research and was recently named a Hanna H. Gray Fellow by the Howard Hughes Medical Institute.
“Having my first graduate student be selected is one of the proudest moments of my career,” said Matthew DeGennaro, a neurogeneticist in FIU's Biomolecular Sciences Institute and Raji’s Ph.D. advisor at FIU.
Raji studied biology in college and went on to earn a master’s in cell biology and genetics at the University of Lagos. That wasn’t enough for him, though. Vaccines can help prevent illness. Treatments can help cure the infected. But neither stop the mosquito. Raji wanted to devote his career to research in the hopes of finding a magic bullet — one that would solve the scourge of mosquito-borne diseases for good.
In 2015, he traveled 6,000 miles from his native Nigeria to FIU and joined DeGennaro’s lab, which focuses on molecular and genetic approaches to prevent mosquito-borne diseases. Four years later, DeGennaro and his research team published a paper in Current Biology focused on IR8a — a single olfactory receptor in mosquitoes — announcing to the world that they had identified the gene mosquitoes rely on to detect people. Raji, still a Ph.D. student at the time, was the lead author. The finding created a monumental shift in mosquito research, giving scientists a roadmap to reinvent how to think about mosquito prevention. Today, researchers are exploring new repellant designs that could target the IR8a gene. Innovations are being explored for new traps and other methods of mosquito population control.
At Johns Hopkins, Raji works in the lab of Christopher Potter studying the malaria-spreading Anopheles mosquitoes. He is searching for molecular targets that drive mosquitoes’ attraction to people and the human odors most crucial in activating these targets. What he finds could give rise to new tools to protect people from mosquitoes and the diseases they transmit.
“I am proud of the groundbreaking work he has done in my lab and what he is now achieving at Johns Hopkins University,” DeGennaro said. “I expect Josh to continue to make significant contributions to our field and help the fight against mosquito-borne illnesses.”HHMI’s Hanna H. Gray Fellows Program is dedicated to increasing diversity in biomedical science by recruiting and retaining individuals from groups currently underrepresented in the life sciences and by creating inclusive environments in which all scientists can thrive. Raji is one of 25 fellows selected in the current class to receive funding for their postdoctoral training.