225 - Utilizing Wide Area Larvicide Spraying (WALS) to control Aedes aegypti populations in Albuquerque, New Mexico

Thursday, March 26, 2026

8:50 AM - 9:00 AM PDT

Location: B110

Presenter(s)

Jessica T. Martin, PhD (she/her/hers)

Environmental Health Scientist
Environmental Health Department, City of Albuquerque, New Mexico, United States

Co-Author(s)

JS

Jessie L. Smith, n/a

Environmental Health Technician II
Environmental Health Department, City of Albuquerque, New Mexico, United States
NP

Nicholas D. Pederson, n/a

Environmental Health Manager
Environmental Health Department, City of Albuquerque, New Mexico, United States
EE

Ella Eleven, n/a

Intern
Rockies and High Plains Vector-Borne Diseases Center, Colorado State University, New Mexico, United States
AG

Autumn Good, n/a

Intern
Rockies and High Plains Vector-Borne Diseases Center, Colorado State University, New Mexico, United States
MW

Morgan Waterman, n/a

Intern
Rockies and High Plains Vector-Borne Diseases Center, Colorado State University, New Mexico, United States
CB

Carlos Betancourt, n/a

Vector Control Technician
Planning and Development Services, Bernalillo County, New Mexico, United States
OB

Orlando Benavidez, n/a

Vector Control Technician
Planning and Development Services, Bernalillo County, New Mexico, United States
DP

Dianne Peterson, MSc

Graduate student
University of New Mexico, New Mexico, United States
JA

Jacob Anderson, n/a

Intern
Wesleyan University, Connecticut, United States
MD

Mark A. DiMenna, PhD

Deputy Director
Environmental Health Department, City of Albuquerque, New Mexico, United States

Abstract: Aedes aegypti was first detected in Albuquerque, New Mexico in 2018, and has since become established in the area. Traditional control methods, particularly adulticides, have been relatively ineffective against this increasingly abundant species. To evaluate an alternative control strategy, we conducted a field trial in three pairs of Albuquerque neighborhoods from June to September 2025. Three sites received larvicide applications using Wide Area Larvicide Spraying (WALS), while the other three sites served as untreated controls. Adult mosquito surveillance was conducted for twelve weeks using BG-Sentinel traps to monitor mosquito abundance. Treated sites received WALS applications weekly for four weeks, followed by biweekly applications for an additional four weeks, for a total of six treatments. To assess larvicide deposition and persistence under field conditions, bioassay cups were deployed in front and back yards of the treatment neighborhoods, and subsequently tested for larval mortality in the laboratory. Average larval mortality was 88.4 ± 4.39 SE % when assay cups were collected 0–2d post-treatment, but declined to 20.45 ± 8.96 SE % after 3d, indicating product degradation in hot and dry conditions. Reductions in adult Ae. aegypti abundance varied among treated neighborhoods, with 50% and 29% decreases observed in two neighborhoods relative to their paired controls, while one site had 11% more Ae. aegypti relative to its paired control site. Variation in efficacy may reflect wind patterns, neighborhood structure, and surrounding land use. Overall, these results indicate that WALS can reduce Ae. aegypti populations under arid urban conditions, although effectiveness was site-dependent and influenced by local environmental and meteorological factors.