Article

Dengue Infection Increases the Locomotor Activity of Aedes aegypti Females

Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil.
PLoS ONE (Impact Factor: 3.23). 03/2011; 6(3):e17690. DOI: 10.1371/journal.pone.0017690
Source: PubMed

ABSTRACT

Aedes aegypti is the main vector of the virus causing Dengue fever, a disease that has increased dramatically in importance in recent decades, affecting many tropical and sub-tropical areas of the globe. It is known that viruses and other parasites can potentially alter vector behavior. We investigated whether infection with Dengue virus modifies the behavior of Aedes aegypti females with respect to their activity level.
We carried out intrathoracic Dengue 2 virus (DENV-2) infections in Aedes aegypti females and recorded their locomotor activity behavior. We observed an increase of up to ∼50% in the activity of infected mosquitoes compared to the uninfected controls.
Dengue infection alters mosquito locomotor activity behavior. We speculate that the higher levels of activity observed in infected Aedes aegypti females might involve the circadian clock. Further studies are needed to assess whether this behavioral change could have implications for the dynamics of Dengue virus transmission.

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    • "Virus infection may alter mosquito motility or feeding behavior (Berry et al. 1986, Platt et al. 1997, Lee et al. 2000). For example, in Aedes aegypti (L.) infected with dengue virus, locomotor activity was increased compared with uninfected controls (Lima-Camara et al. 2011). Conversely, when Aedes trivittatus Coquillett were infected with trivittatus virus, there was no significant difference in spontaneous flight activity compared with uninfected controls (Berry et al. 1987). "
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    • "Microbial challenges can disrupt patterns of locomotion and physiological function. Increased activity was documented in female Aedes aegypti within 2–6 days after infection with Dengue virus, likely because this virus targets nervous tissues (Camara et al. 2011 ). Circadian control of activity was rapidly disrupted in D. melanogaster injected with the grampositive bacteria Streptococcus pneumonia and Listeria monocytogenes (). "
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    • "albopictus females when testing flight, sugar-feeding and host-seeking activities under laboratory conditions [18,28,29]. In addition, under laboratory conditions, it has been reported that parasite-vector interactions, such as dengue virus- Ae. aegypti infection, as well as genetic mutations which denote insecticide resistance by the vector do not change the pattern of activity of Ae. aegypti, but increase the locomotor activity of females [24,30]. Although it has been reported that physiological states, such as insemination and blood-feeding, affect the flight activity of Ae. aegypti females [18], it has not been evaluated up to now how drastic changes in these physiological states could affect the locomotor activity pattern of Ae. aegypti and Ae. "
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