RESUMO
Aedes aegypti and Culex quinquefasciatus are disease vectors distributed throughout much of the world and are responsible for a high burden of vector-borne disease, which has increased during the last 2 decades. Most pathogens vectored by these mosquitoes do not have therapeutic remedies; thus, combating these diseases is dependent upon vector control. Improvements in vector control strategies are urgently needed, but these hinge on understanding the biology and ecology of Ae. aegypti and Cx. quinquefasciatus. Both species have been extensively investigated, but further knowledge on diel resting activity of these vectors can improve vector surveillance and control tools for targeting resting vector populations. From April to December 2021, we determined outdoor daytime resting habits of Ae. aegypti and Cx. quinquefasciatus male, female, and blood-fed female populations in Reynosa, Mexico, using large red odor-baited wooden box traps. The daytime resting activity for Ae. aegypti males, females, and blood-fed females was restricted to a period between 0900 h and 1300 h, with a peak at 0900 h, while the resting activity of Cx. quinquefasciatus male, female, and blood-fed females was between 0700 h and 1100 h, with a peak at 0700 h. A generalized additive model was developed to relate relative humidity and temperature to resting Cx. quinquefasciatus and Ae. aegypti male, female, and blood-fed populations caught in traps. This study advances the understanding of outdoor resting behavior for 2 important vector mosquito species and discusses future studies to fill additional knowledge gaps.
RESUMO
La malaria en Venezuela es altamente heterogénea y focalizada. En 2016 se reportaron más de 242 mil casos nuevos en el país, de los cuales 73% provenían del estado Bolívar, 42% del municipio Sifontes y 29% de la parroquia San Isidro. Entre octubre 2016 y mayo 2017 se realizó en la parroquia San Isidro un estudio exploratorio, con el fin de establecer una línea basal entomológica en malaria que permitiera la evaluación posterior de Rociamientos Intradomiciliarios de Insecticida y Mosquiteros Tratados con insecticida de Larga Duracion.Las capturas de mosquitos adultos con Trampas Mosquito Magnet Independence™, atrayente humano y en reposo pre-hematofágico, permitieron determinar que en esta parroquia, hay por lo menos tres especies de anofelinos con actividad hematofágica antropofílica, An. darlingi, An. albitarsis s.l. y An. nuneztovari s.l., cuyos hábitos de reposo y actividad de picada fueron descritos. Asimismo, el muestreo de hábitats larvales permitió determinar que las lagunas residuales de la actividad minera son los más importantes y que An. albitarsis s.l. y An. triannulatus s.l. son las especies de mayor prevalencia en estos hábitats. Estos hallazgos permiten actualizar la data entomológica de este foco caliente de malaria y sientan las bases para la evaluación y seguimiento de las medidas de control de vectores implementadas(AU)
Malaria in Venezuela is highly heterogeneous and focused. In 2016, more than 242,000 malaria cases were reported in the country, from which 73% came from Bolivar state, 42% from Sifontes municipality and 29% from the San Isidro parish. Between October 2016 and May 2017, an exploratory study was carried out in order to establishing an entomologic baseline that would allow posterior evaluations of indoors insecticide spraying and long lasting insecticidal nets. Adults captures with Mosquito Magnet Independence™ traps, human landing, and pre-feedingresting habits allowed to determine that in San Isidro there are at least three anopheline species with significant anthropophilic activity: An darlingi, An. albitarsis s.l. and An. nuneztovari s.l. Resting habits and biting activities were described for the three species. Likewise, larval sampling were carried out which allowed to identify that abandoned gold mine dugouts are the most important habitatsfor these species. Particularly, An. albitarsis s.l. and An. triannulatus s.l. were the most prevalent anophelines colonizing these breeding sites. Our results update entomologic data of this malaria hot spot area and establish the baseline for further evaluations ofthe vector control measures implemented(AU)
Assuntos
Animais , Entomologia/métodos , Malária/prevenção & controle , Venezuela , Mosquitos Vetores , AnophelesRESUMO
We evaluated how the presence of sugar sources impacted the distribution of Aedes aegypti in different habitats in Durán, Ecuador. Land cover and normalized difference vegetation index maps were used to guide a random point sampling routine to select study grids (30 m × 30 m) in low vegetation (LV) and high vegetation (HV). Five individual plants, at one home in the LV and HV grid, were treated with a different colored, non-attractive, 60% sucrose solution to determine mosquito feeding and movement. Sugar alone is not attractive to mosquitoes, so spraying vegetation with a dyed sugar solution can be used for visual determination of sugar feeding. Outdoor collections using BG sentinel traps and indoor collections using aspirators were conducted at the treatment home and with collection points at 20, 40, and 60 m surrounding the treatment home for three consecutive days. A total of 3,245 mosquitoes in two genera, Aedes and Culex, was collected. The proportion of stained Ae. aegypti females was 56.8% (510/898) and 0% for males. For Culex, 63.9% (248/388) females and 36.1% (140/388) males were collected stained. Aedes aegypti and Culex spp. were found up to 60 m stained in both LV and HV grids. Significantly more stained females Ae. aegypti were found inside homes compared to females and males of Culex spp. in both habitats. This study identifies that outdoor sugar feeding is a common behavior of Ae. aegypti and can be targeted as a control strategy in urban habitats in Latin America.