Aedes Mosquito Biology and Behavior

Laura C. Harrington, PhD

Professor, Department of Entomology

Cornell University, Ithaca, NY

Asian tiger mosquitoYellow fever mosquito

Asian bush mosquito

Aedes mosquitoes introduced into the USA

Asian tiger mosquito

(Aedes albopictus)

Yellow fever mosquito

(Aedes aegypti)

Aedes mosquitoes introduced into the USA

One of the most invasive

species in the world

Outline

• Life history, ecology and identification of Aedes container

breeding mosquitoes

•Identification of Aedes container breeding mosquitoes

•unique biology and habit differences from the rest of

commonly encountered mosquitoes

•Geographic presence, range expansion

•Changing environment and challenges for surveillance and

control

• Aedes larvae hatch upon stimulation (flooding, reduced

O2)

• breaking out of the shell using an egg tooth located on

the head

Larvae: respiration and feeding

Short breathing siphon

Trachea enter the siphon and

breathing occurs through spiracles

Larvae hangs at angle to respire and

feed just below the water column

• Mosquito larvae feed on particles

in the water column including:

organic detritis

protozoa

small bacteria

fungi/algae

• Drinking water essential

• Sensitive to changes in light, physical

currents that indicate predators

•pupal stage non-feeding

•respiration through trumpets

•able to move to evade predation

Predators

•Insects (dragonfly larvae and other aquatic insect predators)

•Toxorhynchites mosquito larvae

•Copepods

•Fish

Host seeking

• several stages activation (low or high light intensity)

orientation (visual and chemical, heat (<20 m)

landing

probing

Timing of feeding

Aedes/Ochlerotatus – daytime feeders

Anopheles- nighttime, dawn/dusk

feeders

Culex-nighttime feeders

Adult feeding

•preference for host varies by species

•human feeding = anthropophilic

•animal feeding=zoophilic

•bird feeding= ornithophilic

•generalist feeding

Yellow fever

mosquito

Asian tiger

mosquito

Blood feeding patterns of Thai dengue vectors

Swine + Human

Dog + Human

2.5%

2.5%

95% Human

Blood is essential for egg production

Pathogens are ingested by the mosquito, after

incubation period, and can be injected into a new

host

Blood digestion

Plant sugar feeding can be common

and improves fitness

Egg laying in natural and man-made

containers

These mosquitoes have a

short flight range (often

moving 0-less than 100 m)

Outline

• Life history, ecology and identification of Aedes container

breeding mosquitoes

•Identification of Aedes container breeding mosquitoes

•unique biology and habit differences from the rest of

commonly encountered mosquitoes

•Geographic presence, range expansion

•Changing environment and challenges for surveillance and

control

Adult Identification- Asian tiger

Source

http://fmel.ifas.ufl.edu/key/

Larval Identification- Asian tiger mosquito

Adult Identification- Yellow fever mosquito

Source

http://fmel.ifas.ufl.edu/key/

Larval Identification- Yellow fever mosquito

Outline

• Life history, ecology and identification of Aedes container

breeding mosquitoes

•Identification of Aedes container breeding mosquitoes

•unique biology and habit differences from the rest of

commonly encountered mosquitoes

•Geographic presence, range expansion

•Changing environment and challenges for surveillance and

control

What makes the yellow fever mosquito unique as a

vector?

• Preference for humans

• Close association and contact with humans

• Multiple feeding behavior

• Stealthy biter

• Ability to breed in very small containers

Ae. aegypti is a domesticated

mosquito

Humans provide housing/shelter

Humans provide larval habitat

Humans provide blood

Why is the Asian tiger mosquito such a invader?

• Egg stage and

container-aided dispersal

• Hibernation (Diapause)

• Larval competition

Eggs can be transported long

distances in a dry state

Larval habitat

Tree holes

Lucky bamboo

Plant Nurseries

Bromeliads

Catch basins

/construction

material

Cemetary vases junkyards

Outline

• Life history, ecology and identification of Aedes container

breeding mosquitoes

•Identification of Aedes container breeding mosquitoes

•unique biology and habit differences from the rest of

commonly encountered mosquitoes

•Geographic presence, range expansion

•Changing environment and challenges for surveillance and

control

Global map of the distribution of yellow fever mosquito

Points represent known occurrences (transient [triangles] or established [circles]) until the

end of 2013. Kraemer et al. eLife 2015;4:e08347

US map of the distribution of yellow fever mosquito

Points represent known occurrences (transient [triangles] or established [circles]) until the

end of 2013. Kraemer et al. eLife 2015;4:e08347

US distribution of Ae. albopictus

Regions in which Ae. albopictus is rapidly expanding its range. Points represent known

occurrences (transient [triangles] or established [circles]) until the end of 2013.

Kraemer et al. eLife 2015;4:e08347

Outline

• Life history, ecology and identification of Aedes container

breeding mosquitoes

•Identification of Aedes container breeding mosquitoes

•unique biology and habit differences from the rest of

commonly encountered mosquitoes

•Geographic presence, range expansion

•Changing environment and challenges for surveillance and

control

• Temperature drives development of the mosquito and

the pathogen, increases vector host contact and

increases population size

Climate change influences mosquito vectors and

disease transmission

Warming winter temperatures can increase survival of

overwintering mosquitoes

• Extreme rainfall events can increase breeding site

availability leading to larger vector populations,

higher humidity can increase vector survival rate

Control and prevention

“ avoid bug bites”

“Use repellent”

Source Reduction or Treating

Containers?

Figure 1. Dissemination station (DS) used for “auto-dissemination” experiments in Rome.

Caputo B, Ienco A, Cianci D, Pombi M, Petrarca V, et al. (2012) The “Auto-Dissemination” Approach: A Novel Concept to Fight Aedes

albopictus in Urban Areas. PLoS Negl Trop Dis 6(8): e1793. doi:10.1371/journal.pntd.0001793

http://journals.plos.org/plosntds/article?id=info:doi/10.1371/journal.pntd.0001793

Wolbachia and Genetic Modification

Harringtonlab.blogs.cornell.edu

David F. Duneau