Culex pipiens forms and urbanization: effects on blood feeding sources and transmission of avian Plasmodium

A crucial, but unresolved question concerning mosquito-borne virus transmission is how these viruses can remain endemic in regions where the transmission is halted for long periods of time, due to mosquito inactivity in, e.g., winter. In northern Europe, Sindbis virus (SINV) (genus alphavirus, Togaviridae) is transmitted among birds by Culex mosquitoes during the summer, with occasional symptomatic infections occurring in humans. In winter 2018–19, we sampled hibernating Culex spp females in a SINV endemic region in Sweden and assessed them individually for SINV infection status, blood-feeding status, and species. The results showed that 35 out of the 767 collected mosquitoes were infected by SINV, i.e., an infection rate of 4.6%. The vast majority of the collected mosquitoes had not previously blood-fed (98.4%) and were of the species Cx. pipiens (99.5%). This is the first study of SINV overwintering, and it concludes that SINV can be commonly found in the hibernating Cx. pipiens population in an endemic region in Sweden, and that these mosquitoes become infected through other means besides blood-feeding. Further studies on mosquito ecology and viral interactions are needed to elucidate the mechanisms of the persistence of these viruses over winter.

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Diapause in the mosquito Culex pipiens evokes a metabolic switch from blood feeding to sugar gluttony

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0507958102 ◽

2005 ◽

Vol 102 (44) ◽

pp. 15912-15917 ◽

Cited By ~ 96

Author(s):

R. M. Robich ◽

D. L. Denlinger

Keyword(s):

Culex Pipiens ◽

Blood Feeding ◽

Metabolic Switch

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Blood-feeding habits of nulliparous Culex pipiens molestus

Medical Entomology and Zoology ◽

10.7601/mez.28.225 ◽

1977 ◽

Vol 28 (2) ◽

pp. 225-230

Author(s):

Takeshi KURIHARA ◽

Yuuki ESHITA

Keyword(s):

Culex Pipiens ◽

Feeding Habits ◽

Blood Feeding ◽

Culex Pipiens Molestus

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BLOOD-FEEDING IN OVERWINTERING CULEX TARSALIS (DIPTERA: CULICIDAE) FROM MANITOBA

The Canadian Entomologist ◽

10.4039/ent11485-1 ◽

1982 ◽

Vol 114 (1) ◽

pp. 85-86 ◽

Cited By ~ 1

Author(s):

P. W. Arntfield ◽

W. J. Gallaway ◽

R. A. Brust

Keyword(s):

Low Temperature ◽

Blood Meal ◽

Culex Pipiens ◽

Blood Feeding ◽

Culex Tarsalis ◽

Culex Restuans ◽

Diapause Development

Diapause development in Culex tarsalis Coquillett has been characterized by reduced blood-feeding to complete termination of ovariole development at or before stage IIa (Bennington et al. 1958; Schaefer and Washino 1970; Schaefer et al. 1971; Bellamy and Corbet 1973; Mitchell 1979). The role that diapausing Culex species have in overwintering arboviruses has been examined (Eldridge 1966, 1968; Eldridge et al. 1972; Reeves 1974; Eldridge and Bailey 1979; Mitchell 1979). Gonotrophic dissociation and its implications for survival of the vector and virus has been reviewed by Washino (1977). Eldridge (1966) indicated gonotrophic dissociation was possible in Culex pipiens L. incubated at low temperature and short daylength and later reported failure of ovarioles of prehibernating C. pipiens to mature following a blood meal (Eldridge and Bailey 1979). Eldridge et al. (1972) reported that Culex restuans Theobald exhibited gonotrophic dissociation in response to conditioning by short daylength and low temperature. Mitchell (1981) has reported blood-feeding and gonotrophic dissociation in a significant portion of diapausing Culex tarsalis from Colorado, when females were kept at 15°C and at short daylength conditions.

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Differentiation of Host-Seeking Behavior from Blood-Feeding Behavior in Overwintering Culex Pipiens (Diptera: Culicidae) and Observations on Gonotrophic Dissociation

Journal of Medical Entomology ◽

10.1093/jmedent/20.2.157 ◽

1983 ◽

Vol 20 (2) ◽

pp. 157-163 ◽

Cited By ~ 27

Author(s):

Carl J. Mitchell

Keyword(s):

Feeding Behavior ◽

Culex Pipiens ◽

Blood Feeding ◽

Host Seeking ◽

Seeking Behavior

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Trypanosoma cruzi infection in Triatoma infestans and high levels of human–vector contact across a rural-to-urban gradient in the Argentine Chaco

Parasites & Vectors ◽

10.1186/s13071-020-04534-z ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Alejandra Alvedro ◽

María Sol Gaspe ◽

Hannah Milbourn ◽

Natalia Paula Macchiaverna ◽

Mariano Alberto Laiño ◽

...

Keyword(s):

Trypanosoma Cruzi ◽

Rural Areas ◽

Control Strategies ◽

Blood Feeding ◽

Urban Setting ◽

Transmission Risk ◽

Triatoma Infestans ◽

Urban Gradient ◽

Urban Settings ◽

Feeding Sources

Abstract Background Peri-urban and urban settings have recently gained more prominence in studies on vector-borne transmission of Trypanosoma cruzi due to sustained rural-to-urban migrations and reports of urban infestations with triatomines. Prompted by the finding of Triatoma infestans across the rural-to-urban gradient in Avia Terai, an endemic municipality of the Argentine Chaco, we assessed selected components of domestic transmission risk in order to determine its variation across the gradient. Methods A baseline vector survey was conducted between October 2015 and March 2016, following which we used multistage random sampling to select a representative sample of T. infestans at the municipal level. We assessed T. cruzi infection and blood-feeding sources of 561 insects collected from 109 houses using kinetoplast DNA-PCR assays and direct enzyme-linked immunosorbent assays, respectively. We stratified triatomines according to their collection site (domestic or peridomestic), and we further categorized peridomestic sites in ecotopes of low- or high-risk for T. cruzi infection. Results The overall adjusted prevalence of T. cruzi-infected T. infestans was 1.8% (95% confidence interval [CI] 1.3–2.3) and did not differ between peri-urban (1.7%) and rural (2.2%) environments. No infection was detected in bugs captured in the urban setting; rather, infected triatomines were mainly collected in rural and peri-urban domiciles, occurring in 8% of T. infestans-infested houses. The main blood-feeding sources of domestic and peridomestic triatomines across the gradient were humans and chickens, respectively. The proportion of triatomines that had fed on humans did not differ between peri-urban (62.5%) and rural (65.7%) domiciles, peaking in the few domestic triatomines collected in urban houses and decreasing significantly with an increasing proportion of chicken- and dog- or cat-fed bugs. The relative odds ratio (OR) of having a T. cruzi infection was nearly threefold higher in bugs having a blood meal on humans (OR 3.15), dogs (OR 2.80) or cats (OR: 4.02) in a Firth-penalized multiple logistic model. Conclusions Trypanosoma cruzi transmission was likely occurring both in peri-urban and rural houses of Avia Terai. Widespread infestation in a third of urban blocks combined with high levels of human–triatomine contact in the few infested domiciles implies a threat to urban inhabitants. Vector control strategies and surveillance originally conceived for rural areas should be tailored to peri-urban and urban settings in order to achieve sustainable interruption of domestic transmission in the Chaco region.

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Studies on the Feeding Habits ofLutzomyia (Lutzomyia) longipalpis(Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) Populations from Endemic Areas of American Visceral Leishmaniasis in Northeastern Brazil

Journal of Tropical Medicine ◽

10.1155/2012/858657 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 28

Author(s):

Margarete Martins dos Santos Afonso ◽

Rosemere Duarte ◽

José Carlos Miranda ◽

Lindenbergh Caranha ◽

Elizabeth Ferreira Rangel

Keyword(s):

Visceral Leishmaniasis ◽

Feeding Habits ◽

Blood Feeding ◽

Northeastern Brazil ◽

Sand Fly ◽

Lutzomyia Longipalpis ◽

Elisa Technique ◽

Endemic Areas ◽

Feeding Sources

The aim of this study was to identify potential blood feeding sources ofL. (L.) longipalpisspecimens from populations in Northeastern Brazil, endemic areas of American Visceral Leishmaniasis (AVL) and its correlation with the transmission ofL. (L.) i. chagasi. The ELISA technique was applied using bird, dog, goat, opossum, equine, feline, human, sheep, and rodent antisera to analyze 609 females, resulting in an overall positivity of 60%. In all municipalities, females showed higher positivity for bird followed by dog antiserum and sand fly specimens were also positive for equine, feline, human, sheep, goat, opossum, and rodent antisera. The finding for 17 combinations of two or three types of blood in some females corroborates the opportunistic habit of this sand fly species. The results demonstrating the association betweenL. (L.) longipalpisand opossum suggest the need for further evaluation of the real role of this synanthropic mammal in the eco-epidemiology of AVL.

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