Bromeliad-inhabiting mosquitoes in an urban botanical garden of dengue endemic Rio de Janeiro - Are bromeliads productive habitats for the invasive vectors Aedes aegypti and Aedes albopictus?

Abstract

Immatures of both Aedes aegypti and Aedes albopictus have been found in water-holding bromeliad axils in Brazil. Removal of these plants or their treatment with insecticides in public and private gardens have been undertaken during dengue outbreaks in Brazil despite uncertainty as to their importance as productive habitats for dengue vectors. From March 2005-February 2006, we sampled 120 randomly selected bromeliads belonging to 10 species in a public garden less than 200 m from houses in a dengue-endemic neighborhood in Rio de Janeiro. A total of 2,816 mosquito larvae and pupae was collected, with an average of 5.87 immatures per plant per collection. Culex (Microculex) pleuristriatus and Culex spp of the Ocellatus Group were the most abundant culicid species, found in all species of bromeliads; next in relative abundance were species of the genus Wyeomyia. Only two individuals of Ae. aegypti (0.07%) and five of Ae. albopictus (0.18%) were collected from bromeliads. By contrast, immatures of Ae. aegypti were found in manmade containers in nearly 5% of nearby houses. These results demonstrate that bromeliads are not important producers of Ae. aegypti and Ae. albopictus and, hence, should not be a focus for dengue control. However, the results of this study of only one year in a single area may not represent outcomes in other urban localities where bromeliads, Ae. aegypti and dengue coincide in more disturbed habitats.

Effect of tank bromeliad micro-environment on Aedes aegypti larval mortality

“…This process could explain, at least partially, the results found by Mocellin et al (2009) in Rio de Janeiro, where densities of A. aegypti larvae tend to be lower inside bromeliads when compared to neighboring manmade impoundments.…”

The community of Diptera (Insecta) colonizing axils of Alocasia macrorrhizos (L.) G.Don (Araceae), with records of Aedes aegypti (L.) and Aedes albopictus (Skuse) in urban areas of Manaus, Amazonas

“…albopictus was found in low number and with sporadic nature of occurrence, as shown by the low index of positivity for both species. As demonstrated in other studies in urban areas (Mocellin et al 2009;Santos et al 2011), this kind of habitat (axils of plants) does not seem to play an important role as breeding site for the larvae of these mosquitoes, being the water held in manmade containers the main oviposition sites for Ae. aegypti and Ae.…”

“…In Brazil, Ae. albopictus has been previously found in phytotelmata, such as holes in trees, bamboo internodes (Gomes et al 1992, Muller & Marcondes 2010) and bromeliads (Marques et al 2001, Mocellin et al 2009.…”

Ocorrência de Aedes aegypti e Aedes albopictus em bromélias cultivadas no Jardim Botânico Municipal de Bauru, São Paulo, Brasil

“…O número de larvas de mosquitos encontrado nas bromélias neste trabalho foi baixo se comparado com estudos realizados em áreas urbanas e periurbanas, que correspondem a maioria dos trabalhos 8,9,10,11 . O baixo número de larvas possivelmente está relacionado à localização do Jardim Botânico Municipal de Bauru, distante cerca de um quilômetro de áreas residenciais e inserido em um grande fragmento florestal, reforçando a predileção de diversas espécies de mosquitos por áreas urbanas.…”