scholarly journals Larval Susceptibility of Two Culex quinquefasciatus Populations (Diptera: Culicidae) Temephos® in the City of Naviraí, MS, Brazil

Author(s):  
Cintia Granzotti da Silva Scudeler ◽  
Eduardo José Arruda ◽  
Carlos Fernando Salgueirosa Andrade ◽  
Tania Granzotti Silva ◽  
Magda Freitas Fernandes ◽  
...  
Author(s):  
María Florencia Branda ◽  
Magdalena Laurito ◽  
Andrés Mario Visintin ◽  
Walter Ricardo Almirón

Abstract The subgenus Culex L. includes species involved in summer–autumn arbovirus transmission but studies during winter are scarce in temperate Argentina. Female specimens were collected host-seeking at dry-ice-baited traps during autumn–winter–spring at two sites in Córdoba City during 2016 and 2017. The specimens were morphologically identified and dissected to determine the follicular developmental stage (gonotrophic activity). Females with advanced follicular stages (≥III) were subjected to molecular procedures to confirm or re-identify previous morphological identification. Five species (Culex apicinus Philippi (Diptera: Culicidae), Culex dolosus (Lynch-Arribálzaga) (Diptera: Culicidae), Culex maxi Dyar (Diptera: Culicidae), Culex pipiens pipiens L. (Diptera: Culicidae), and Culex quinquefasciatus Say (Diptera: Culicidae)) were collected and found gonoactive during winter; showing that a high proportion of Culex (Culex) females remain reproductively active during the unfavorable season for mosquito populations. Among them, it is worth noting the collection of Cx. quinquefasciatus, vector of the St. Louis encephalitis virus (endemic in the city), a specimen of Cx. p. pipiens, and a hybrid of Cx. p. pipiens/Cx. quinquefasciatus (during autumn). The study of this community during winter should continue because a high gonoactive female proportion with advanced follicular stages was found: 29.12 and 13.07% in 2016 and 2017, respectively. Local studies such as this one provide evidence about ornithophilic Culex species with active year-round life cycles, species that could favor arbovirus overwintering.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Abdou Talipouo ◽  
Konstantinos Mavridis ◽  
Elysée Nchoutpouen ◽  
Borel Djiappi-Tchamen ◽  
Emmanouil Alexandros Fotakis ◽  
...  

AbstractCulex mosquitoes particularly Culex quinquefasciatus are important arboviral and filariasis vectors, however despite this important epidemiological role, there is still a paucity of data on their bionomics. The present study was undertaken to assess the insecticide resistance status of Cx. quinquefasciatus populations from four districts of Yaoundé (Cameroon). All Culex quinquefasciatus populations except one displayed high resistance to bendiocarb and malathion with mortalities ranging from 0 to 89% while high resistance intensity against both permethrin and deltamethrin was recorded. Molecular analyses revealed high frequencies of the ACE-1 G119S mutation (ranging from 0 to 33%) and kdr L1014F allele (ranging from 55 to 74%) in all Cx. quinquefasciatus populations. Significant overexpression was detected for cytochrome P450s genes CYP6AA7 and CYP6Z10, as well as for Esterase A and Esterase B genes. The total cuticular hydrocarbon content, a proxy of cuticular resistance, was significantly increased (compared to the S-lab strain) in one population. The study confirms strong insecticide resistance mediated by different mechanisms in Cx. quinquefasciatus populations from the city of Yaoundé. The expansion of insecticide resistance in Culex populations could affect the effectiveness of current vector control measures and stress the need for the implementation of integrated vector control strategies in urban settings.


Author(s):  
Sabrina Ribeiro Santana ◽  
Pâmela dos Santos Andrade ◽  
Paulo Roberto Urbinatti ◽  
Rosa Maria Marques de Sá Almeida ◽  
Tamara Nunes Lima-Camara

2018 ◽  
Vol 28 (2) ◽  
pp. 154-157
Author(s):  
K. Demba Kodindo ◽  
A. Kana-Mbang ◽  
T. Moundai ◽  
A. Nakebang Fadel ◽  
E. Yangalbé-Kalnoné ◽  
...  

2012 ◽  
Vol 78 (17) ◽  
pp. 6321-6326 ◽  
Author(s):  
Karlos Diogo de Melo Chalegre ◽  
Tatiany Patrícia Romão ◽  
Daniella Aliny Tavares ◽  
Eloína Mendonça Santos ◽  
Lígia Maria Ferreira ◽  
...  

ABSTRACTBin toxin fromBacillus sphaericusacts onCulex quinquefasciatuslarvae by binding to Cqm1 midgut-bound receptors, and disruption of thecqm1gene is the major cause of resistance. The goal of this work was to screen for a laboratory-selected resistancecqm1RECallele in field populations in the city of Recife, Brazil, and to describe other resistance-associated polymorphisms in thecqm1gene. Thecqm1RECallele was detected in the four nontreated populations surveyed at frequencies from 0.001 to 0.017, and sequence analysis from these samples revealed a novel resistant allele (cqm1REC-D16) displaying a 16-nucletotide (nt) deletion which is distinct from the 19-nt deletion associated withcqm1REC. Yet a third resistant allele (cqm1REC-D25), displaying a 25-nt deletion, was identified in samples from a treated area exposed toB. sphaericus. A comparison of the three deletion events revealed that all are located within the same 208-nt region amplified during the screening procedure. They also introduce equivalent frameshifts in the sequence and generate the same premature stop codon, leading to putative transcripts encoding truncated proteins which are unable to locate to the midgut epithelium. The populations analyzed in this study contained a variety of alleles with mutations disrupting the function of the corresponding Bin toxin receptor. Their locations reveal a hot spot that can be exploited to assess the resistance risk through DNA screening.


1999 ◽  
Vol 27 (2) ◽  
pp. 202-203
Author(s):  
Robert Chatham

The Court of Appeals of New York held, in Council of the City of New York u. Giuliani, slip op. 02634, 1999 WL 179257 (N.Y. Mar. 30, 1999), that New York City may not privatize a public city hospital without state statutory authorization. The court found invalid a sublease of a municipal hospital operated by a public benefit corporation to a private, for-profit entity. The court reasoned that the controlling statute prescribed the operation of a municipal hospital as a government function that must be fulfilled by the public benefit corporation as long as it exists, and nothing short of legislative action could put an end to the corporation's existence.In 1969, the New York State legislature enacted the Health and Hospitals Corporation Act (HHCA), establishing the New York City Health and Hospitals Corporation (HHC) as an attempt to improve the New York City public health system. Thirty years later, on a renewed perception that the public health system was once again lacking, the city administration approved a sublease of Coney Island Hospital from HHC to PHS New York, Inc. (PHS), a private, for-profit entity.


ASHA Leader ◽  
2013 ◽  
Vol 18 (7) ◽  
pp. 46-48

This year's Annual Convention features some sweet new twists like ice cream and free wi-fi. But it also draws on a rich history as it returns to Chicago, the city where the association's seeds were planted way back in 1930. Read on through our special convention section for a full flavor of can't-miss events, helpful tips, and speakers who remind why you do what you do.


ASHA Leader ◽  
2017 ◽  
Vol 22 (7) ◽  
Author(s):  
Sean Sweeney
Keyword(s):  

2009 ◽  
Author(s):  
Ferdinand Gregorovius ◽  
Annie Hamilton

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