Published: 10/17/2023

Mosquito-transmitted virus infections are on the rise and their spread is accelerating in Texas, Florida and elsewhere in the American South. With the rise of mosquito-borne illnesses, infectious disease experts at Stanford School of Medicine and Baylor College of Medicine and are predicting the possible re-emergence of yellow fever in the southern portion of the U.S. Their perspective piece on the virus’ potential return was published recently in the New England Journal of Medicine. It calls for yellow fever to be prioritized in national pandemic preparedness planning.

“The mosquitoes that spread yellow fever are here in the US, and conditions are increasingly favorable for them as our world warms,” said Desiree LaBeaud, MD, MS, professor of Pediatric Infectious Disease at Stanford Medicine and co-author of the paper. “We need a comprehensive plan to better protect at-risk communities in the southern U.S. from mosquito-borne diseases.”

Dr. Desiree LaBeaud, Stanford Medicine
Dr. Peter Hotez, Baylor College of Medicine

Yellow fever is a mosquito-borne viral illness that decimated southern U.S. cities in regular epidemics in New Orleans, Galveston, Memphis and Charleston from 1820 to 1905, according to the paper’s co-author and tropical disease expert Peter Hotez, MD, PhD. Hotez is professor and dean of the National School of Tropical Medicine at Baylor and co-director of the Texas Children’s Hospital Center for Vaccine Development.

The virus is a flavivirus and arbovirus infection like dengue or Zika virus, but with much higher mortality. Yellow fever is transmitted by Aedes mosquitoes, which are common in the Caribbean and Latin America, as well as southern urban areas like those in Texas and Florida.

“We’ve seen a rise in mosquito-transmitted illnesses in Texas and Florida, including malaria, dengue, chikungunya and Zika virus, but now we’re also worried about yellow fever since it seems to be accelerating in tropical regions of Latin America such as Brazil and Venezuela,” Hotez said. “The consequences of a high mortality infection like yellow fever re-emerging in the southern U.S. would be profoundly destabilizing.”

Experts propose expanding surveillance activities by enhancing local health departments to combat mosquitoes and mosquito-borne illnesses as well as developing antiviral drugs, vaccines and new gene drive technology (permanently altering insect genes through genetic engineering) for mosquito control efforts.

“One of the reasons we established National School of Tropical Medicine at Baylor was in recognition that tropical infections have become a new normal due to a confluence of climate change, urbanization and poverty on the U.S. Gulf Coast and Texas,” Hotez said.

This news story was adapted by a press release from Baylor College. Read it here.

Photo credit: CDC/ Amy E. Lockwood, MS