Aedes aegypti Mosquitos Found in Fresno. So far, they've tested negative for the deadly viruses they transmit

Hello everyone!

In summer 2013, I traveled to the Peruvian Amazon to study mosquito ecology. Somewhat ironically, I got sick with dengue (or possible chikungunyua, the diagnosis was never conclusive). Seeing that these mosquitos are spreading north is a bit unsettling for someone who knows personally what the viruses they carry are capable of! Dengue and chikungunya are mosquito-borne viruses that cause rashes, fever (sometimes hemorrhagic in the case of dengue), bone/muscle pain among numerous symptoms. These viruses can be deadly if the patient doesn't get proper medical attention!

With the ebola epidemic ravaging West Africa, it’s easy to forget that we in the United States may not be safe from outbreaks either. Last week, the mosquito Aedes aegypti was found in Fresno when distric health workers placed 120 mosquito traps throughout the city.

Aedes aegypti, adult, Pialoux et al 2007

When they checked the traps, they found the Aedes larvae. A. aegypti is thought to have originated from Africa, although it has spread throughout the tropics.

Fresno isn’t that far from us! (Google Maps)

Why are these mosquitos interesting? They are known to transmit several deadly viral diseases that may soon spread from the tropics: yellow fever, dengue fever and chikungunya. Infections from these viruses can cause fever, severe headaches and even death in extreme cases. None of the mosquitos the health department found tested positive for any of these viruses, but should one of the mosquitos bite a person who traveled to a region with endemic dengue, chikungunya or yellow fever. These viruses reproduce in the guts of mosquitos, as well as in human cells. When a mosquito bites an infected human, it can contract the virus and transmit it to its next victim. Our warming, increasingly interconnected world is allowing these mosquitos, and possibly the viruses they transmit, to spread to higher latitudes. 

References:

http://www.fresnobee.com/2014/09/22/4138718/mosquito-that-can-spread-yellow.html

http://www.cdc.gov/dengue/

http://www.cdc.gov/chikungunya/

Google Maps

Gubler, Duane. "Dengue/Dengue Hemorrhagic Fever: The Emergence Of A Global Health Problem." Emerging Infectious Diseases 1.2 (1995): 55-57. Print.

Pialoux, Gilles, Bernard-Alex Gaüzère, Stéphane Jauréguiberry, and Michel Strobel. "Chikungunya, an epidemic arbovirosis." The Lancet Infectious Diseases 7.5 (2007): 319-327. Print.
Mousson, Laurence, Catherine Dauga, Thomas Garrigues, Francis Schaffner, Marie Vazeille, and Anna-Bella Failloux. 

"Phylogeography of Aedes ( Stegomyia ) aegypti (L.) and Aedes ( Stegomyia ) albopictus (Skuse) (Diptera: Culicidae) based on mitochondrial DNA variations."Genetical Research 86.01 (2005): 1. Print.

--by Joe Getsy '15