12 research outputs found
Efficacy of novel indoor residual spraying methods targeting pyrethroid-resistant aedes aegypti within experimental houses
Challenges in maintaining high effectiveness of classic vector control in urban areas has renewed the interest in indoor residual spraying (IRS) as a promising approach for Aedes-borne disease prevention. While IRS has many benefits, application time and intrusive indoor applications make its scalability in urban areas difficult. Modifying IRS to account for Ae. aegypti resting behavior, named targeted IRS (TIRS, spraying walls below 1.5 m and under furniture) can reduce application time; however, an untested assumption is that modifications to IRS will not negatively impact entomological efficacy. We conducted a comparative experimental study evaluating the residual efficacy of classically-applied IRS (as developed for malaria control) compared to two TIRS application methods using a carbamate insecticide against a pyrethroid-resistant, field-derived Ae. aegypti strain. We performed our study within a novel experimental house setting (n = 9 houses) located in Merida (Mexico), with similar layouts and standardized contents. Classic IRS application (insecti-cide applied to full walls and under furniture) was compared to: a) TIRS: insecticide applied to walls below 1.5 m and under furniture, and b) Resting Site TIRS (RS-TIRS): insecticide applied only under furniture. Mosquito mortality was measured eight times post-application (out to six months post-application) by releasing 100 Ae. aegypti females/house and collecting live and dead individuals after 24 hrs exposure. Compared to Classic IRS, TIRS and RS-TIRS took less time to apply (31% and 82% reduction, respectively) and used less insecticide (38% and 85% reduction, respectively). Mortality of pyrethroid-resistant Ae. aegypti did not significantly differ among the three IRS application methods up to two months post application, and did not significantly differ between Classic IRS and TIRS up to four months post application. These data illustrate that optimizing IRS to more efficiently target Ae. aegypti
Characteristics of the Baja California Pacific Islands where breeding seabird populations were monitored during the period 2003–2019.
Characteristics of the Baja California Pacific Islands where breeding seabird populations were monitored during the period 2003–2019.</p
Seabirds with a positive regional population trend on the Baja California Pacific Islands for the period 2014–2019.
For an increasing population, the following null hypothesis was tested: H0: λ≤1, pα = 0.1.</p
Population trends per taxonomic group.
Points represent the hierarchical bootstrapped means from the medians of the population growth rates (λ) shown in S1 Table. Bars represent the 95% bootstrap interval. The horizontal dashed line shows λ = 1 which indicates no population change.</p
Summary of population trends for 61 colonies of 19 seabird species on 10 islands and archipelagos in the Mexican Pacific off the Baja California Peninsula.
Summary of population trends for 61 colonies of 19 seabird species on 10 islands and archipelagos in the Mexican Pacific off the Baja California Peninsula.</p
Population trends for 19 seabird species at their colonies on 10 islands/archipelagos in the Mexican Pacific off the Baja California Peninsula.
A 95% bootstrap interval was calculated for population growth rates (λ) using moving block bootstrap; central value, lower and upper limits are given. Percent change was estimated using Eq (2) for the period described. aIsland/archipelago ordered North to South. bN indicates the most recent count of breeding pairs with the year in parentheses. cIncreasing (+); Decreasing (-); Not Determined (ND). (XLSX)</p
Map of the Baja California Pacific Islands, a seabird hotspot where breeding populations have been systematically monitored for almost two decades.
Photos of Coronado Archipelago and San Roque islands are shown—being the extremes in geographic location—to show the heterogeneous physiography of the region’s islands. Arrows depict the southerly flow of the California Current [51], which has significant influence on the region’s marine productivity and thus the seabird populations. Map design credits: © GECI / Gabriela Fernández Ham. Photo credits: © GECI / J.A. Soriano.</p
Database of maximum number of breeding pairs used to estimate the population growth rates for seabirds on the Baja California Pacific Islands.
(XLSX)</p