Article

Early evening questing and oviposition activity by the Culex (Diptera: Culicidae) vectors of West Nile virus in northeastern North America.

Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA.
Journal of Medical Entomology (Impact Factor: 1.86). 04/2007; 44(2):211-4. DOI: 10.1603/0022-2585(2007)44[211:EEQAOA]2.0.CO;2
Source: PubMed

ABSTRACT To determine whether the Culex (Diptera: Culicidae) mosquitoes that transmit West Nile virus (family Flaviviridae, genus Flavivirus, WNV) in the northeastern United States seek hosts and oviposit contemporaneously, we recorded when these mosquitoes attacked caged birds and when they deposited eggs. They traversed oviposition sites most frequently approximately 2 h after astronomical sunset, and eggs generally were deposited at that time. Although they most frequently approached avian hosts approximately 2 h after sunset during midsummer, they are more opportunistic during mid- to late fall. Because the Culex mosquitoes that serve as the main vectors of West Nile virus in the northeastern United States quest for hosts and seek to oviposit well after sunset, insecticidal aerosols would be most effective when applied at that time.

0 Bookmarks
 · 
94 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: : Mosquito host-seeking activity was studied using a custom-designed trap to explore: (1) at which time interval of the night adult mosquito abatement would be most effective, and (2) if there exists an avian-specific host-seeking preference. Overnight trials using traps baited with dry ice showed that Aedes taeniorhynchus (Wiedemann) was most active at dusk and was then captured throughout the night. In contrast, Culex spp. (Cx. pipiens (Linnaeus) and Cx. restuans (Theobald) delayed most activity until about two h after dusk and were then captured through the night. This pattern suggests that management activities directed at adult Culex spp. would be most effective if initiated well after sunset. Mosquito capture rates in traps baited with birds in net bags were significantly greater than those with empty net bags, indicating that mosquitoes were attracted to the birds and not incidentally being sucked in by the custom trap's strong fan motor (Wilcoxon matched-pairs signed-ranks test, n= 24, t= 30, p < 0.05). Regression analysis showed that bird weight influenced mosquito attraction (r2= 0.21, p= 0.02). Trials with paired traps that contained different native bird species showed that Gray Catbirds, Dumatella carolinensis, attracted more mosquitoes than the heavier Northern Cardinals, Cardinalis cardinalis (paired samples t-test, t= 2.58, df= 7, p= 0.04). However, attractiveness did not differ substantially among bird species, and Gray Catbirds did not attract more mosquitoes than all other birds combined as a group. American Robins, Turdus migratorius (n = 4) were comparable in attractiveness to other bird species, but not enough American Robins were captured for a comprehensive study of mosquito avian preference.
    Journal of Vector Ecology - J VECTOR ECOL. 01/2010; 35(1):69-74.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Oviposition response of gravid Culex quinquefasciatus females to a series of synthetic fatty acid esters was evaluated at 10ppm under laboratory conditions. Octyl tridecanoate and propyl octadecanoate elicited respectively 85% and 73% increased ovipositional responses compared to control among the 16 esters tested. Other 14 esters showed highly significant repellency (67-96%) to gravid females. Standard 3-methyl indole received 69% increased egg deposition compared to control. In the Y-tube olfactometer, respectively 78, 64 & 58% orientation to octyl tridecanoate, propyl octadecanoate and 3-methyl indole was exhibited by the gravid C. quinquefasciatus females. Gravid females exhibited 19-41% reduced orientation toward treatment odors of other esters significantly different from respective control. Electroantennogram studies revealed 4-18 fold increased antennal response, in which 3-methyl indole, octyl tridecanoate and propyl octadecanoate elicited respectively 8, 18 and 15 fold EAG response compared to control. Relative EAG response of octyl tridecanoate compared to standard 3-methyl indole was significantly different. Reduced EAG responses were elicited by FAE-06, 08, 13, 14 & 15, while the relative EAG responses of other esters were at par with the standard stimulus. These, esters could be utilized potentially as oviposition attractants and repellents against C. quinquefasciatus females to reduce the breeding in polluted water along with existing integrated vector control methods.
    Acta tropica 09/2013; 128(3):606-612. · 2.79 Impact Factor
  • Source

Full-text

Download
54 Downloads
Available from
May 23, 2014