Effects of anthropogenic landscape changes on the abundance and acrodendrophily of Anopheles (Kerteszia) cruzii, the main vector of malaria parasites in the Atlantic Forest in Brazil

Abstract

Background The mosquito Anopheles ( Kerteszia ) cruzii is the main vector of human and simian malaria in the Atlantic Forest. This species is usually abundant in the forests where it occurs, preferring to live and feed on canopies, behaviour known as acrodendrophily. However, in several studies and locations this species has been observed in high density near the ground in the forest. In this study, it was hypothesized that factors associated with anthropogenic landscape changes may be responsible for the variation in abundance and acrodendrophily observed in An. cruzii . Methods The study was conducted in a conservation unit in the city of São Paulo, Brazil. Monthly entomological collections were performed from March 2015 to April 2017, and the resulting data were used with data from another study conducted in the same area between May 2009 and June 2010. Mosquitoes were collected from five sites using CDC and Shannon traps. Landscape composition and configuration metrics were measured, and generalized linear mixed-effect models were used to investigate the relationship between these metrics and variations in the abundance and acrodendrophily of An. cruzii . Results The model that showed the best fit for the relationship between landscape metrics and An. cruzii abundance suggests that an increase in the proportion of forest cover leads to an increase in the abundance of this mosquito, while the model that best explained variations in An. cruzii acrodendrophily suggests that an increase in total forest-edge length leads to greater activity by this species at ground level. Conclusion While the data indicate that changes in landscape due to human activities lead to a reduction in An. cruzii abundance, such changes may increase the contact rate between this species and humans living on the edges of forest fragments where An. cruzii is found. Future studies should, therefore, seek to elucidate the effect of these landscape changes on the dynamics of Plasmodium transmission in the Atlantic Forest, which according to some studies includes the participation of simian hosts. Electronic supplementary material The online version of this article (10.1186/s12936-019-2744-8) contains supplementary material, which is available to authorized users.

Zika and dengue viruses infecting wild-caught mosquitoes in an environmental protection area in Brazil

“…Many studies have reported the presence of mosquitoes that are considered important flavivirus vectors in fragments of the Atlantic Forest in various areas in the city of São Paulo [18,34-36] and state of São Paulo [4,37,38], but natural flavivirus infection in these mosquitoes had not been detected prior to the present study. This is also the first report of mosquitoes naturally infected with flaviviruses in a conservation unit in the city of São Paulo.…”

“…The greatest diversity of Culicidae in Brazil is probably found in the Atlantic Forest [18], and several remnants of the Atlantic Forest can be found in various areas of the city of São Paulo, ranging from urban parks to conservation units. Conservation units farthest from the city center tend to be more preserved and consequently have greater mosquito diversity [18,34]. While the Capivari-Monos EPA is still a well-preserved area, it has recently undergone anthropic modifications that have led to fragmentation of the landscape [17,34].…”

“…Conservation units farthest from the city center tend to be more preserved and consequently have greater mosquito diversity [18,34]. While the Capivari-Monos EPA is still a well-preserved area, it has recently undergone anthropic modifications that have led to fragmentation of the landscape [17,34].…”

Horizontal distribution affects the vertical distribution of native and invasive container‐inhabitingAedesmosquitoes within an urban landscape

“…Only a few studies to date have addressed the question of the interaction between the horizontal and the vertical distribution of mosquitoes (Laporta and Sallum 2014, Medeiros‐Sousa et al 2019, Obenauer et al 2009). Studies in the Atlantic forest of Brazil have investigated patterns of species co‐occurrence along natural and anthropogenic gradients and how these affect horizontal and vertical distribution as well mechanisms of coexistence and mosquito community structure (Laporta and Sallum 2014, Medeiros‐Sousa et al 2019). Laporta and Sallum (2014) demonstrated that the coexistence of Wyeomyia.…”

“…Quasilongirostris is enabled via vertical habitat partitioning only at an ecotonal scrub‐forest ecotone but not in any of the other distinct habitats (Laporta and Sallum 2014). Furthermore, Medeiros‐Sousa et al (2019) showed that in anthropogenically disturbed forests, the malaria vector Anopheles cruzii, which typically inhabits the canopy, tends to increases its activity at ground level. In North America, Obenauer et al (2009) reported that in the forest habitat, Ae.…”