Chikungunya and mosquito vectors

We investigated the role of socio-economic factors in the proliferation of mosquito vectors in two adjacent but socio-economically contrasting neighborhoods in Baton Rouge, LA, USA. We surveyed mosquito larvae habitat, mosquito larvae, and adult mosquitoes during the summer of 2020. We also evaluated the number of requests for mosquito abatement services in the years preceding the study for each area. While we did not find differences in terms of the most abundant species, Culex quinquefasicatus (F1,30 = 0.329, p = 0.57), we did find a higher abundance of mosquito habitats, particularly discarded tires, as well as larvae (z = 13.83, p < 0.001) and adults (F1,30 = 4.207, p = 0.049) of the species Aedes albopictus in the low-income neighborhood. In contrast, mosquito abatement requests were significantly higher in the high socio-economic neighborhood (z = −8.561, p < 0.001). This study shows how factors such as adjudicated properties, discarded tires and pest abatement requests can influence the abundance of mosquito vectors, disproportionately affecting low-income groups. This study also highlights how Aedes spp. may be better indicators than Culex spp. of socio-economic differences between nearby neighborhoods, due to their short flight range and habitat preferences, and this should be considered in future studies attempting to detect such disparities in the future.

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Blood parasites of bird communities in Sri Lanka and their mosquito vectors

Parasitology Research ◽

10.1007/s00436-021-07049-3 ◽

2021 ◽

Vol 120 (2) ◽

pp. 693-703

Author(s):

W. G. D. Chathuranga ◽

B. R. Fernando ◽

T. C. Weereratne ◽

S. H. P. P. Karunaratne ◽

W. A. Priyanka P. De Silva

Keyword(s):

Sri Lanka ◽

Bird Communities ◽

Blood Parasites ◽

Mosquito Vectors

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Ligusticum sinense Nanoemulsion Gel as Potential Repellent against Aedes aegypti, Anopheles minimus, and Culex quinquefasciatus (Diptera: Culicidae)

Insects ◽

10.3390/insects12070596 ◽

2021 ◽

Vol 12 (7) ◽

pp. 596

Author(s):

Anuluck Junkum ◽

Wanchai Maleewong ◽

Atiporn Saeung ◽

Danita Champakaew ◽

Arpaporn Chansang ◽

...

Keyword(s):

Aedes Aegypti ◽

Culex Quinquefasciatus ◽

Disease Transmission ◽

Skin Irritation ◽

Mosquito Vectors ◽

Plant Family ◽

Anopheles Minimus ◽

Human Volunteers ◽

Nanoemulsion Gel ◽

Fresh Preparation

Ligusticum sinense Oliv. cv. is a species of Umbelliferae (Apiaceae), a large plant family in the order Apiales. In this study, L. sinense hexane extract nanoemulsion gel (LHE-NEG) was investigated for mosquito repellency and compared to the standard chemical, N,N-diethyl-3-methylbenzamide (DEET), with the goal of developing a natural alternative to synthetic repellents in protecting against mosquito vectors. The results demonstrated that LHE-NEG afforded remarkable repellency against Aedes aegypti, Anopheles minimus, and Culex quinquefasciatus, with median protection times (MPTs) of 5.5 (4.5–6.0), 11.5 (8.5–12.5), and 11.25 (8.5–12.5) h, respectively, which was comparable to those of DEET-nanoemulsion gel (DEET-NEG: 8.5 (7.0–9.0), 12.0 (10.0–12.5), and 12.5 (10.0–13.5) h, respectively). Evaluation of skin irritation in 30 human volunteers revealed no potential irritant from LHE-NEG. The physical and biological stability of LHE-NEG were determined after being kept under heating/cooling cycle conditions. The stored samples of LHE-NEG exhibited some changes in appearance and differing degrees of repellency between those kept for 3 and 6 heating/cooling cycles, thus providing slightly shorter MPTs of 4.25 (4.0–4.5) and 3.25 (2.5–3.5) h, respectively, when compared to those of 5.0 (4.5–6.0) h in fresh preparation. These findings encourage commercially developed LHE-based products as an alternative to conventional synthetic repellents in preventing mosquito bites and helping to interrupt mosquito-borne disease transmission.

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Chikungunya and Zika Viruses: Co-Circulation and the Interplay between Viral Proteins and Host Factors

Pathogens ◽

10.3390/pathogens10040448 ◽

2021 ◽

Vol 10 (4) ◽

pp. 448

Author(s):

Sineewanlaya Wichit ◽

Nuttamonpat Gumpangseth ◽

Rodolphe Hamel ◽

Sakda Yainoy ◽

Siwaret Arikit ◽

...

Keyword(s):

Antiviral Drug ◽

Virus Transmission ◽

Antiviral Agent ◽

Viral Proteins ◽

Targeted Therapeutics ◽

Limited Information ◽

Mosquito Vectors ◽

Host Proteins ◽

Host Interactions ◽

Viral Host Interactions

Chikungunya and Zika viruses, both transmitted by mosquito vectors, have globally re-emerged over for the last 60 years and resulted in crucial social and economic concerns. Presently, there is no specific antiviral agent or vaccine against these debilitating viruses. Understanding viral–host interactions is needed to develop targeted therapeutics. However, there is presently limited information in this area. In this review, we start with the updated virology and replication cycle of each virus. Transmission by similar mosquito vectors, frequent co-circulation, and occurrence of co-infection are summarized. Finally, the targeted host proteins/factors used by the viruses are discussed. There is an urgent need to better understand the virus–host interactions that will facilitate antiviral drug development and thus reduce the global burden of infections caused by arboviruses.

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Efficacy of broflanilide (VECTRON T500), a new meta-diamide insecticide, for indoor residual spraying against pyrethroid-resistant malaria vectors

Scientific Reports ◽

10.1038/s41598-021-86935-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Corine Ngufor ◽

Renaud Govoetchan ◽

Augustin Fongnikin ◽

Estelle Vigninou ◽

Thomas Syme ◽

...

Keyword(s):

Indoor Residual Spraying ◽

Malaria Vectors ◽

Cross Resistance ◽

Malaria Vector Control ◽

Mosquito Vectors ◽

Experimental Huts ◽

Application Rates ◽

Wettable Powder ◽

Cone Bioassay ◽

Pirimiphos Methyl

AbstractThe rotational use of insecticides with different modes of action for indoor residual spraying (IRS) is recommended for improving malaria vector control and managing insecticide resistance. Insecticides with new chemistries are urgently needed. Broflanilide is a newly discovered insecticide under consideration. We investigated the efficacy of a wettable powder (WP) formulation of broflanilide (VECTRON T500) for IRS on mud and cement wall substrates in laboratory and experimental hut studies against pyrethroid-resistant malaria vectors in Benin, in comparison with pirimiphos-methyl CS (Actellic 300CS). There was no evidence of cross-resistance to pyrethroids and broflanilide in CDC bottle bioassays. In laboratory cone bioassays, broflanilide WP-treated substrates killed > 80% of susceptible and pyrethroid-resistant An. gambiae sl for 6–14 months. At application rates of 100 mg/m2 and 150 mg/m2, mortality of wild pyrethroid-resistant An. gambiae sl entering experimental huts in Covè, Benin treated with VECTRON T500 was similar to pirimiphos-methyl CS (57–66% vs. 56%, P > 0.05). Throughout the 6-month hut trial, monthly wall cone bioassay mortality on VECTRON T500 treated hut walls remained > 80%. IRS with broflanilide shows potential to significantly improve the control of malaria transmitted by pyrethroid-resistant mosquito vectors and could thus be a crucial addition to the current portfolio of IRS insecticides.

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