Comparison of capture methods for the diagnosis of adult anopheline populations from State of Mato Grosso, Brazil

Abstract

Introduction: The present study compares human landing catches of primary malaria vectors with two alternative methods of capture: the Shannon trap and the Mosquito magnet. Methods: This study used regression models to adjust capture data to a negative binominal distribution. Results: Capture numbers and relative percentages obtained from the three methods vary strongly between species. The highest overall captures were obtained for Anopheles triannulatus with captures for the Shannon trap and the Mosquito magnet measuring more than 330% higher than captures obtained by human landings. For Anopheles darlingi, captures by the Shannon trap and the Mosquito magnet were about 14% and 26% of human landing catches, respectively. Another species with malaria transmission potential that was not sampled by human landing captures weascaptured by the Shannon trap and the Mosquito magnet (Anopheles oswaldoi). Both alternative sampling techniques can predict the human landing of Anopheles triannulatus, but without proportionality. Models for Anopheles darlingi counts, after totaling daily captures, are significant and proportional, but prediction models are more reliable when using the Shannon trap compared with the Mosquito magnet captures. Conclusions: These alternative capture methods can be partially recommended for the substitution of human landing captures or, at least, as complementary forms of monitoring for malarial mosquitoes.

Brazilian mosquito (Diptera: Culicidae) fauna: I. Anopheles species from Porto Velho, Rondônia state, western Amazon, Brazil

“…Shannon traps allow the capture of adult females attracted by light and humans near the collection area. According to MISSAWA et al 23 , Shannon traps can be used as alternatives to human baiting for capture of anthropophilic mosquitoes in studies that have the objective of detecting the presence of vectors. Due to the light effects, this technical alternative is useful to sort a lot of mosquito's species.…”

Development and optimization of the Suna trap as a tool for mosquito monitoring and control

“…Historically, the most commonly used tool for monitoring malaria vectors was the human landing catch (HLC). This approach is considered to provide the best measure of man-biting rate and peak time of biting in a specific time and place [13-17]. Given the potential for exposure of volunteers to infective mosquito bites, as well as non-standardized trapping due to variation between the attractiveness of volunteers, and their ability to catch mosquitoes in the process of biting, an effective non-biased mosquito sampling tool, such as a trap, is needed.…”

Is there an efficient trap or collection method for sampling Anopheles darlingi and other malaria vectors that can describe the essential parameters affecting transmission dynamics as effectively as human landing catches? - A Review

“…nuneztovari and Anopheles triannulatus s.l. , but the results have been inconclusive (Eiras & Jepson 1991, Rubio-Palis & Curtis 1992, Rubio-Palis 1996, Rubio-Palis et al 1999, 2012, Gama et al 2007, 2013, Hiwat et al 2011a, b, Missawa et al 2011 , JBP Lima et al, unpublished observations ) . Therefore, according to the most recent studies, the human landing catch is the collection method of choice for Neotropical anthropophilic anophelines.…”

“…Nonetheless, it has also been concluded that the yields of anthropophilic anophelines can be enhanced by the use of human odour as an attractant in physical/chemical-type traps, such as the CDC without light (Hiwat et al 2011a, b), the Mosquito Magnet ® (Hiwat et al. 2011a, b, Rubio-Palis et al 2012), the BG-Sentinel ® (Hiwat et al 2011a, b) or the BG-Malaria (Gama et al 2013) traps and by the use of the biological-type traps, such as protected human collectors in Shannon-type traps (Hiwat et al 2011b, Missawa et al 2011, JBP Lima et al, unpublished observations). Based on these findings and conclusions, we formulated questions and carried out experiments years ago that we will describe and discuss in the following section.…”

“…However, the collection of intradomiciliary resting females using knockdown and entry/exit collection methods can be used to answer questions related to resting and endophilic behaviours and to determine the blood source of engorged females (Service 1993, Service & Townson 2002, Harbison et al 2006). In Brazil and other malaria-endemic territories in the American continents, studies of alternative anopheline collection methods to human landing catches are still scarce and restricted to a few research groups (Eiras & Jepson 1991, Rubio-Palis & Curtis 1992, Rubio-Palis 1996, Rubio-Palis et al 1999, 2012, Gama et al 2007, 2013, Missawa et al 2011, JBP Lima et al, unpublished observations ) . Our results show that the development of Shannon-type traps with biological/chemical attractants using either whole organisms or molecules derived from the host should be investigated.…”