A NativeWolbachiaEndosymbiont Does Not Limit Dengue Virus Infection in the MosquitoAedes notoscriptus(Diptera: Culicidae)

Abstract

The endosymbiotic bacterium Wolbachia pipientis infects many species of insects and has been transinfected into the mosquito Aedes aegypti (L.), the primary vector of dengue virus (DENV). Recently, it has been shown that Wolbachia blocks the replication and transmission of RNA viruses, such as DENV, in a number of mosquito species including Ae. aegypti and Aedes albopictus (Skuse), which is naturally infected with Wolbachia and considered a secondary vector for DENV. The mosquito species Aedes notoscriptus (Skuse) is highly prevalent in Australia, including in areas where DENV outbreaks have been recorded. The mosquito has been implicated in the transmission of Ross River and Barmah Forest viruses, but not DENV. We investigated whether Wolbachia naturally infects this mosquito species and whether it has an impact on the ability of Ae. notoscriptus to transmit DENV. We show, for the first time, that Ae. notoscriptus is naturally infected with a strain of Wolbachia that belongs to supergroup B and is localized only in the ovaries. However, Wolbachia infection in Ae. notoscriptus did not induce resistance to DENV and had no effect on overall DENV infection rate or titer. The presence of a native Wolbachia in Ae. notoscriptus cannot explain why this mosquito is an ineffective vector of DENV.

Detection of Wolbachia in Aedes albopictus and Their Effects on Chikungunya Virus

“…Unlike the case for transinfected hosts, effect of Wolbachia on virus replication in native hosts has been reported to be inconsistent. For instance, the naturally occurring Wolbachia of Aedes notoscriptus do not induce DENV interference within the native hosts22 contrary to the report on Ae. albopictus that demonstrated that native Wolbachia can limit transmission of DENV 23.…”

Wolbachiaincreases the susceptibility of a parasitoid wasp to hyperparasitism

“…These studies are mostly laboratory based, with just a few using natural host populations (Skelton et al, 2016;Zele et al, 2014), and only some with parasitoids rather than pathogen infection (Fytrou et al, 2006;Hsiao, 1996;Martinez et al, 2012;Xie et al, 2014). In order to understand the complex role of endosymbionts, such studies should also be conducted under natural conditions, and in a broad range of host taxa.…”

Infection of anopheline mosquitoes with Wolbachia: Implications for malaria control

“…However, the effect of Wolbachia on viruses is strain and host specific. For example, native Wolbachia had no effect on DENV infection in Aedes notoscriptus [ 13 ].…”