Sindbis Virus Infection Alters Blood Feeding Responses and DEET Repellency in Aedes aegypti (Diptera: Culicidae)

Abstract

Aedes aegypti (L.) (Diptera: Culicidae) female mosquitoes infected systemically with Sindbis virus (SINV) took longer than uninfected mosquitoes to locate and fully engorge on blood. On days 7 and 14 postexposure, blood feeding took 1.3 and 1.5 times longer in mosquitoes with a disseminated SINV infection, respectively. SINV dissemination did not affect the average weight of unfed Ae. aegypti, but did result in a 10 and 12% increase in blood imbibed compared with mosquitoes without a positive SINV dissemination and non-SINV-exposed mosquitoes, respectively. Ae. aegypti mosquitoes with a disseminated SINV infection fed an average of 4 h sooner than uninfected mosquitoes when offered a bloodmeal contained inside a DEET (N,N-diethyl-3-methylbenzamide) saturated (30%) bovine sausage casing. Together, these results indicate that behavioral changes in mosquito host-seeking, blood feeding and sensitivity to DEET occurred in mosquitoes after SINV infection and dissemination.

Does Zika virus infection affect mosquito response to repellents?

“…Sindbis virus (SINV) infection has been shown to alter Ae. aegypti females’ responses to DEET 14 27 28 , but, on the other hand, no significant differences were observed in responses of DENV-infected mosquitoes 18 29 . There are significant differences in methodology between studies that prevent us from reconciling our data.…”

“…Although contact repellents (contact disengagents) are invaluable in preventing mosquito bites, spatial repellents are preferred for skin application given that viruses may be transmitted while a mosquito is probing the skin prior to initiating a blood meal 12 . Additionally, virus replication in the salivary glands may affect the gustatory system 13 and, consequently, reduce contact repellency sensitivity 14 .…”

Infection pattern and transmission potential of chikungunya virus in two New World laboratory-adapted Aedes aegypti strains

“…In our study, however, CHIKV also infected the medial salivary gland lobes (in HWE mosquitoes) and induced apoptosis in this tissue. It has been suggested that apoptosis in the salivary glands may be due to cellular homeostasis as well as antiviral defence and may affect virus concentrations in saliva 42 51 52 . As apoptosis was detected in CHIKV-infected salivary gland tissue but not in uninfected salivary glands (apart from the saliva ducts), it remains to be investigated whether CHIKV-induced apoptosis quantitatively affects the release of virus along with mosquito saliva.…”

Molecular determinants of arbovirus transmission by mosquitoes

“…Furthermore, altered bloodfeeding behaviour, including more frequent probing, has been reported in dengue virus (DENV), La Crosse virus and Sindbis virus (SINV) infected Ae. aegypti mosquitoes [505][506][507][508][509]. Decreased host-seeking behaviour and reduced mobility could result in a smaller number of feeding events, thus, lowering the vectorial capacity.…”