(Vax-Before-Travel News)
A recent study, the first of its kind, has shown that certain tropical mosquitoes can carry disease-causing pathogens over long distances and at high altitudes.
Researchers reported in the journal PNAS on November 25, 2025, that mosquitoes captured at higher elevations were infected with 21 arboviruses, protozoans, and parasitic worms associated with diseases that affect humans—among them dengue fever, malaria, and West Nile.
This undetected, high-altitude transportation system may be key to initiating outbreaks at distant locations, these researchers wrote.
The old hypothesis that mosquito-borne pathogens are spread over large distances by wind-borne mosquitoes at altitude was based on epidemiological and meteorological inferences and on sporadic observations of mosquitoes at altitude.
These researchers wrote that it was not widely accepted because it lacked direct evidence for the regularity and scales of such movements and infection with mosquito-borne pathogens in wind-borne mosquitoes at altitude.