Clinical Center News
September 2017

Healthy volunteers endure mosquito bites to advance research

Women with arm over canister of mosquitoes
Research volunteer Melissa Meerdter holds her arm over the canister during the controlled exposure to biting mosquitoes in the Special Clinical Studies Unit on Aug. 25.

Doctor looks at healthy participants arm for mosquito bites
Dr. Matthew J. Memoli (left), director of the Clinical Studies Unit in National Institute of Allergy and Infectious Diseases Laboratory of Infectious Diseases and principal investigator of the trial, count the number of visible bites with research volunteer Melissa Meerdter.
 

Mosquitoes beware! Researchers within the Clinical Center began a Phase 1 clinical trial this year to protect humans against mosquito-transmitted diseases. The trial, led by the National Institute of Allergy and Infectious Diseases (NIAID), is testing an investigational vaccine intended to provide broad protection against a number of diseases, such as Zika, malaria, West Nile fever and dengue fever by hindering the ability of mosquitoes to transmit such infections.

The investigational vaccine is designed to trigger an immune response to mosquito saliva rather than to a specific virus or parasite carried by mosquitoes.

As of late August, the clinical trial has enrolled 43 participants. Investigators are expected to enroll up to 60 healthy adults ages 18 to 50 years. Participants come to the Clinical Center and receive either an investigational vaccine or a placebo. Approximately 21 days after completing the vaccination schedule, participants return to undergo a controlled exposure to biting mosquitoes. Participants are not at risk of becoming infected with a mosquito-borne disease because the mosquitoes are not carrying viruses or parasites. Up to 10 mosquitoes from the insectary in NIAID's Laboratory of Malaria and Vector Research are put in a feeding device that is then placed on each participant's arm for 20 minutes. The mosquitoes will bite the participants' arms through the netting on the feeding devices.

Afterward, investigators take blood samples from each participant at various time points to see if participants experience a modified response to the mosquito bites as a result of the vaccination.

Two healthy volunteers sit at a table with the researcher as they hold their arm over a canister of mosquitoes
On Aug. 25, research volunteers Catrina Johnson, left, and Michelle Acheampong, right, participate in Dr. Matthew J. Memoli’s clinical trial. The participants are partaking in a controlled exposure to biting mosquitoes.