The use of aquatic predators for larval control of mosquito disease vectors: Opportunities and limitations

Kundu

et al. 2020

Limnological Review

The indirect interactions among multiple prey sharing a common predator characterize apparent competition. In conservation biological control involving mosquitoes and controphic prey against generalist insect predators, apparent competition may be a crucial factor determining the extent of success. The possible influence of apparent competition on mosquito prey consumption by three water bugs (Heteroptera: Nepidae): Ranatra elongata, Ranatra filiformis, and Laccotrephes griseus was assessed under laboratory conditions. Tadpoles (Duttaphrynus melanostictus), chironomid larvae, snails (Racesina luteola) and fish fingerlings (Labeo rohita) were considered as alternative prey under two prey or multi prey conditions against instar IV larvae of Culex quinquefasciatus as target prey. Under two prey conditions all the predators exhibited a preference (significant Manly’s α) for mosquito larvae, against fish fingerlings by R. filiformis. In the presence of multiple prey, mosquito larvae were selected by the predators. Using the ratio of mosquito selectivity in two prey and multi-prey conditions as a measure of apparent competition, chironomid larvae had greatest effect in suppressing mosquito selectivity for R. elongata, and fish fingerlings for R. filiformis and L. griseus. It seems that the prey preference of R. elongata, R. filiformis and L. griseus may differentially evoke apparent competition among the prey. In the aquatic community where these predators and prey coexist, mosquito larvae may benefit from apparent competition that reduces their vulnerability to predators. The identity of the alternative prey appears to be an important factor for shielding the vulnerability of mosquito prey to the generalist insect predators.

Section: Introductionmentioning

confidence: 62%

Section: Ranatra Elongata Ranatra Filiformis Laccotrephes Griseusmentioning

confidence: 99%

Alternative prey influence the predation of mosquito larvae by three water bug species (Heteroptera: Nepidae)

Kundu

et al. 2020

Limnological Review

“…Bacillus sphaericus , Bs) have been successfully applied for mosquito control in various ecological settings in sub Saharan Africa [ 106 ], Europe [ 107 ], Asia [ 108 ] and South America [ 109 ]. Aquatic insect predators and larvivorous fish have also been proposed as mosquito biocontrol agents, however, there is only limited evidence of their impact on disease transmission [ 110 ]. Density, diversity and habitat effects on the efficacy of natural mosquito larvae enemies must be considered.…”

Section: Conventional Measures For Vector Control and Their Limitamentioning

confidence: 99%

Vector-Focused Approaches to Curb Malaria Transmission in the Brazilian Amazon: An Overview of Current and Future Challenges and Strategies

et al. 2020

In Brazil, malaria transmission is mostly confined to the Amazon, where substantial progress has been made towards disease control in the past decade. Vector control has been historically considered a fundamental part of the main malaria control programs implemented in Brazil. However, the conventional vector-control tools have been insufficient to control or eliminate local vector populations due to the complexity of the Amazonian rainforest environment and ecological features of malaria vector species in the Amazon, especially Anopheles darlingi. Malaria elimination in Brazil and worldwide eradication will require a combination of conventional and new approaches that takes into account the regional specificities of vector populations and malaria transmission dynamics. Here we present an overview on both conventional and novel promising vector-focused tools to curb malaria transmission in the Brazilian Amazon. If well designed and employed, vector-based approaches may improve the implementation of malaria-control programs, particularly in remote or difficult-to-access areas and in regions where existing interventions have been unable to eliminate disease transmission. However, much effort still has to be put into research expanding the knowledge of neotropical malaria vectors to set the steppingstones for the optimization of conventional and development of innovative vector-control tools.

“…Bacillus sphaericus, Bs), have been successfully applied for mosquito control in various ecological settings in sub Saharan Africa [94], Europe [95], Asia [96] and South America [97]. Aquatic insect predators and larvivorous fish have also been proposed as mosquito biocontrol agents, however, there is only limited evidence of their impact on disease transmission [98]. Density, diversity and habitat effects on the efficacy of natural mosquito larvae enemies must be considered.…”

Section: Larvae Controlmentioning

confidence: 99%

Vector-focused Approaches to Curb Malaria Transmission in the Brazilian Amazon: An Overview of Current and Future Challenges and Strategies

Rocha¹,

Katak²,

Campos-de-Oliveira³

et al. 2020

Preprint

In Brazil, malaria transmission is mostly confined to the Amazon, where substantial progress has been achieved towards disease control in the past decade. Vector control has been historically considered a fundamental part of the main malaria control programs implemented in Brazil. However, the conventional vector-control tools have been insufficient to eliminate local vector populations due to the complexity of the Amazonian rainforest environment and ecological features of malaria vector species in the Amazon, especially Anopheles darlingi. Malaria elimination in Brazil and worldwide eradication will require a combination of conventional and new approaches that takes into account the regional specificities of vector populations and malaria transmission dynamics. Here we present an overview on both conventional and novel promising vector-focused tools to curb malaria transmission in the Brazilian Amazon. If well designed and employed, these new vector-based approaches may improve the implementation of malaria-control programs, particularly in remote or difficult-to-access areas and in regions where existing interventions have been unable to eliminate disease transmission. However, much effort still has to be put on research expanding the knowledge of neotropical malaria vectors to set the steppingstones for the development of such innovative tools.