Article
Effect of an intervention in storm drains to prevent Aedes aegypti reproduction in Salvador, Brazil
Registro en:
SOUZA, R. L. et al. Effect of an intervention in storm drains to prevent Aedes aegypti reproduction in Salvador, Brazil. Parasites and Vectors, v. 10, p. 328, 2017.
1756-3305
10.1186/s13071-017-2266-6
Autor
Souza, Raquel Lima
Mugabe, Vánio André
Paploski, Igor Adolfo Dexheimer
Rodrigues, Moreno S
Moreira, Patrícia Sousa dos Santos
Nascimento, Leile Camila Jacob
Roundy, Christopher Michael
Weaver, Scott C
Reis, Mitermayer Galvão dos
Kitron, Uriel
Ribeiro, Guilherme de Sousa
Resumen
Brazilian National Council for Scientific and Technological Development (grants 400830/2013-2 and 440891/2016-7 to GSR, and scholarships to IADP, MSR, VAM, UK, MGR and GSR), the Brazilian
Coordination for the Improvement of Higher Education (grant 440891/2016-7 to GSR), and the UTMB’s Institute for Human Infections and Immunity (pilot grant to CR and SW). Aedes aegypti, the principal vector for dengue, chikungunya and Zika viruses, is a synanthropic species that uses stagnant water to complete its reproductive cycle. In urban settings, rainfall water draining structures, such as storm drains, may retain water and serve as a larval development site for Aedes spp. reproduction. Herein, we describe the effect of a community-based intervention on preventing standing water accumulation in storm drains and their consequent infestation by adult and immature Ae. aegypti and other mosquitoes. Methods: Between April and May of 2016, local residents association of Salvador, Brazil, after being informed of
water accumulation and Ae. aegypti infestation in the storm drains in their area, performed an intervention on 52
storm drains. The intervention consisted of placing concrete at the bottom of the storm drains to elevate their
base to the level of the outflow tube, avoiding water accumulation, and placement of a metal mesh covering the
outflow tube to avoid its clogging with debris. To determine the impact of the intervention, we compared the
frequency at which the 52 storm drains contained water, as well as adult and immature mosquitoes using data
from two surveys performed before and two surveys performed after the intervention.
Results: During the pre-intervention period, water accumulated in 48 (92.3%) of the storm drains, and immature
Ae. aegypti were found in 11 (21.2%) and adults in 10 (19.2%). After the intervention, water accumulated in 5 (9.6%)
of the storm drains (P < 0.001), none (0.0%) had immatures (P < 0.001), and 3 (5.8%) contained adults (P = 0.039).
The total number of Ae. aegypti immatures collected decreased from 109 to 0 (P < 0.001) and adults decreased
from 37 to 8 (P = 0.011) after the intervention. Collection of immature and adult non-Aedes mosquitoes (mainly
Culex spp.) in the storm drains also decreased after the intervention.
Conclusion: This study exemplifies how a simple intervention targeting storm drains can result in a major reduction of
water retention, and, consequently, impact Ae. aegypti larval populations. Larger and multi-center evaluations are needed
to confirm the potential of citywide structural modifications of storm drains to reduce Aedes spp. infestation level.