Nearly half聽of the world鈥檚 citizens聽live in areas with a聽risk of catching dengue fever,聽according to聽the Centers for Disease Control and Prevention.聽As聽the mosquito-borne聽illness rapidly聽spreads, especially in the Americas and Caribbean, a聽聽researcher is playing a crucial role in finding solutions.

James聽Earnest, an assistant professor at the Burnett School of Biomedical Sciences, is聽leading聽two聽new聽research projects to examine how humans build an immune response to dengue and the Zika virus over time, in pursuit of creating better preventative measures.

Tackling a Global Problem

Both聽dengue and聽Zika聽are carried by the聽Aedes aegypti聽mosquito,聽which has expanded聽its habitat from Africa to tropical,聽subtropical聽and even聽temperate聽areas worldwide.聽According to the World Health Organization, dengue infections in humans climbed聽from聽505,430 in 2000聽to聽14.6 million in 2024, an increase of more than 2,700%.

Dengue can be asymptomatic or cause severe pain, fatigue and high fever. Repeated infections can be fatal.

Since 2017, there have been few cases of聽Zika聽recorded in the U.S., but the disease persists sporadically in Africa, the Americas and Asia. The virus鈥� biggest health concern is聽for聽pregnant聽women because contracting聽Zika聽can increase risks for聽serious聽congenital birth defects.

While people in Mexico and Uganda聽may聽benefit聽from this research,聽Florida鈥檚 location as a worldwide travel destination聽adds to聽the聽growing聽need for solutions.聽U.S.聽dengue聽cases聽are on the rise and聽have been reported in Florida, California,聽Texas聽and Hawaii. Most are related to travel.聽Dengue is also prevalent in聽Puerto Rico.

鈥淭he threat to the U.S. is growing over time. … We want to be the leaders at looking at these viruses.鈥� 鈥� James Earnest, 麻豆原创 Assistant Professor

鈥淲ith more favorable temperatures and with people traveling around the globe these days, the threat to the U.S. is growing over time,鈥� Earnest says. 鈥淚 think, especially here in Florida, the potential for these mosquitoes to live in these areas and start transmitting these diseases in the very near future is high. 麻豆原创 recognizes that this is an important avenue of research for this region, and so we want to be the leaders at looking at these viruses.鈥�

How the聽麻豆原创聽Research Works

Earnest鈥檚 lab is focused on how the immune system responds to mosquito-borne viruses. Before arriving at 麻豆原创 in 2024, he tracked dengue via longitudinal sampling in Mexico鈥檚 Yucatan Peninsula.

Earnest is collaborating with the Uganda Virus Research Institute (UVRI) through a five-year $970,813 subcontract, part of a larger grant awarded to UVRI from Wellcome, a London-based charitable organization that supports science to solve urgent health challenges. The project aims to study immune system and antibody responses to dengue and Zika in large cohorts of people in Uganda and in Mexico.

麻豆原创 will also collaborate with Emory University on a聽$578,157聽grant from the National Institutes of Health, with Earnest subcontracted to Emory to study whether combining two current dengue inoculations used in Brazil gives humans better protection against repeat infections.

鈥淚t’s important that we understand what good and bad immune responses look like to these viruses.鈥� 鈥� James Earnest, 麻豆原创 Assistant Professor

鈥淚t’s聽important聽that we understand what good and bad immune responses look like to these viruses,鈥澛燛arnest聽says. 鈥淲hen we know those factors, then聽we can try to steer people in聽the right聽direction so that their antibodies will protect them from聽disease.鈥�

Earnest will coordinate with teams in other countries to regularly collect blood samples and measure antibody production to get a comprehensive look at how different people鈥檚 bodies react to dengue and Zika over time. The samples will be collected and processed in Mexico and Uganda, and Earnest will analyze the results in his lab.

鈥淚 think what’s unique about聽this work is that we鈥檙e聽following people over time and not necessarily聽just聽when they get sick,鈥澛燛arnest says.

His research focuses on B cells, which are white blood cells that make antibodies and help the body remember how to fight infections. By tracking how聽people鈥檚聽B cells change over time, his team aims to understand how immune responses differ across regions.

In a related project with Emory, the lab will聽identify聽the most effective memory B cells and antibodies induced by two existing methods of inoculation for dengue, then test whether combining those methods in Brazilian trial participants produces a stronger immune response.

Students Aim to Save Lives Through Lab Work

With this new research,聽Earnest鈥檚 lab has welcomed聽two new 麻豆原创聽students聽who have聽personal聽experience聽with聽dengue and聽Zika.

Maiesha聽Mahmood, a聽second-year聽biotechnology聽master鈥檚 student,聽is from Bangladesh, where the threat of dengue looms.

鈥淚 have been around dengue a lot growing up,鈥� Mahmood聽says.聽鈥淚 know people who have been in hospital聽with聽severe forms聽of dengue, and聽people聽who’ve聽passed away聽suddenly.聽People become scared of mosquitos and dengue.鈥�

She聽says she聽hopes聽麻豆原创鈥檚 research will someday save lives.

鈥淏ack in Bangladesh,聽we don’t really have a lot of facilities that can support virology research,鈥澛爏he says. 鈥淚t was聽a huge opportunity to be able to come here and be able to work聽with Dr. Earnest.聽I want to continue looking into these kinds of聽viruses聽and聽find聽a way to help people who keep suffering from聽these聽diseases.鈥�

叠谤耻苍辞听笔颈苍丑别颈谤辞听鈥�25, a first-year Ph.D. candidate,聽joined Earnest鈥檚 lab聽to further his education and hopes research will聽help people close to him.

鈥淢y family is from Brazil and so聽Zika聽was a very big thing for them,鈥� says聽Pinheiro, who聽earned his bachelor鈥檚 degree in聽biotechnology聽鈥淚t鈥檚 great to work on something that you can feel will impact the community that you’re a part of.鈥�

Researcher Credentials:

Earnest joined 麻豆原创鈥檚 College of Medicine as聽an assistant professor聽in 2024. He聽earned聽his doctorate in聽microbiology and聽immunology from Loyola University Chicago in 2017. He performed postdoctoral research at Washington University in St. Louis studying antibody responses to mosquito-borne viruses and Emory University where he managed clinical field trials in Latin America.

Funding聽and Disclosure:

Research reported in this publication was supported by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health under Award Number U01AI186860. The content is solely the responsibility of the authors and does not necessarily聽represent聽the official views of the National Institutes of Health.