Protective effect of house screening against indoor Aedes aegypti in Mérida, Mexico: A cluster randomised controlled trial

• Published in: Tropical medicine & international health 2021-12, Vol.26 (12), p.1677-1688
• Main Authors: Manrique‐Saide, Pablo, Herrera‐Bojórquez, Josué, Villegas‐Chim, Josué, Puerta‐Guardo, Henry, Ayora‐Talavera, Guadalupe, Parra‐Cardeña, Manuel, Medina‐Barreiro, Anuar, Ramírez‐Medina, Marypaz, Chi‐Ku, Aylin, Trujillo‐Peña, Emilio, Méndez‐Vales, Rosa E., Delfín‐González, Hugo, Toledo‐Romaní, María E., Bazzani, Roberto, Bolio‐Arceo, Edgardo, Gómez‐Dantés, Hector, Che‐Mendoza, Azael, Pavía‐Ruz, Norma, Kirstein, Oscar D., Vazquez‐Prokopec, Gonzalo M.
• Format: Article
• Language: English
• Subjects: Aedes; Aedes - physiology; Aedes - virology; Aedes aegypti; Aedes‐transmitted viruses; Animals; Aquatic insects; arboviruses; Blood; Cluster Analysis; Clusters; Computer viruses; Control methods; Cross-Sectional Studies; Dengue fever; Dengue Virus - isolation & purification; Disease control; Disease transmission; Dry season; Female; Females; Fiberglass; Host-Pathogen Interactions; House screening; Households; Houses; Housing; Humans; Indoor environments; Infestation; Merida; Mexico; Mosquito Control - methods; Mosquitoes; Pesticides; Rainy season; Residential areas; Screening; Vector-borne diseases; Zika Virus - isolation & purification
• ISSN: 1360-2276; 1365-3156
• DOI: 10.1111/tmi.13680

Objective To evaluate the protective effect of house screening (HS) on indoor Aedes aegypti infestation, abundance and arboviral infection in Merida, Mexico. Methods In 2019, we performed a cluster randomised controlled trial (6 control and 6 intervention areas: 100 households/area). Intervention clusters received permanently fixed fiberglass HS on all windows and doors. The study included two cross‐sectional entomologic surveys, one baseline (dry season in May 2019) and one post‐intervention (PI, rainy season between September and October 2019). The presence and number of indoor Aedes females and blood‐fed females (indoor mosquito infestation) as well as arboviral infections with dengue (DENV) and Zika (ZIKV) viruses were evaluated in a subsample of 30 houses within each cluster. Results HS houses had significantly lower risk for having Aedes aegypti female mosquitoes (odds ratio [OR] = 0.56, 95% CI 0.33–0.97, p = 0.04) and blood‐fed females (OR = 0.53, 95% CI 0.28–0.97, p = 0.04) than unscreened households from the control arm. Compared to control houses, HS houses had significantly lower indoor Ae. aegypti abundance (rate ratio [RR] = 0.50, 95% CI 0.30–0.83, p = 0.01), blood‐fed Ae. aegypti females (RR = 0.48, 95% CI 0.27–0.85, p = 0.01) and female Ae. aegypti positive for arboviruses (OR = 0.29, 95% CI 0.10–0.86, p = 0.02). The estimated intervention efficacy in reducing Ae. aegypti arbovirus infection was 71%. Conclusions These results provide evidence supporting the use of HS as an effective pesticide‐free method to control house infestations with Aedes aegypti and reduce the transmission of Aedes‐transmitted viruses such as DENV, chikungunya (CHIKV) and ZIKV.