Genetic study in Aedes (Stegomyia) aegypti (Linnaeus, 1762) from Londrina (Paraná State, Brazil): an approach to population structure and pyrethroid resistance

Abstract Londrina is the fourth most populous city in southern Brazil. Its subtropical weather with rain in all seasons, as well as its high population density, make the city perfect for the Aedes aegypti (Linnaeus, 1762) life cycle. Over the last few years, Londrina presented high infestation indexes and was one of the cities with the most reported cases of dengue. Uncontrolled use of synthetic insecticides may influence the mosquito's genetic composition. In this paper, we studied mitochondrial DNA and kdr mutations in Aedes aegypti. The analysis of the ND4 gene in 330 specimens showed the presence of 27 haplotypes. The pyrethroid resistance alleles (kdr) evaluated are present in the collected populations, with a 50% frequency of the Val1016Ile and 48% of the Phe1534Cys mutations. Such analysis of the mutations in the populations collected at the State University of Londrina's campus - a microenvironment that differs from the rest of the city - showed frequencies of 57% and 62%, respectively. The low gene flow observed, Nm = 0.11 and Nm = 0.10, along with the elevated differentiation, Fst = 0.19 and Fst = 0.18, among populations suggest an influence of genetic drift. The strong presence of resistance alleles kdr in the city is evident, which demonstrates that even with the interruption of the use of pyrethroids by the National Dengue Control Program, resistance may be maintained due to domestic use. Thus, the results have shown the need for genetic monitoring, alongside other entomological surveillance monitoring tools, to create strategies of mosquito control.

Ascogregarina taiwanensis infection in Aedes aegypti and Aedes albopictus in Santa Catarina, South Brazil.

INTRODUCTION: This study registers Ascogregarina spp. infection in field populations of Aedes aegypti and Aedes albopictus in a subtropical region of Brazil. METHODS: Mosquito larvae collected in tires placed in four municipalities of Santa Catarina were identified morphologically and assessed for Ascogregarina sp. infection using morphological and molecular methods. RESULTS: Both mosquito species harbored Ascogregarina taiwanensis, whose genomic DNA was confirmed in both the Aedes species by PCR. DNA sequences were deposited in GenBank. Conclusion: Both Ae. albopictus e Ae. aegypti harbor Ascogregarina sp.

Ascogregarina taiwanensis infection in Aedes aegypti and Aedes albopictus in Santa Catarina, South Brazil

Abstract INTRODUCTION This study registers Ascogregarina spp. infection in field populations of Aedes aegypti and Aedes albopictus in a subtropical region of Brazil. METHODS Mosquito larvae collected in tires placed in four municipalities of Santa Catarina were identified morphologically and assessed for Ascogregarina sp. infection using morphological and molecular methods. RESULTS Both mosquito species harbored Ascogregarina taiwanensis, whose genomic DNA was confirmed in both the Aedes species by PCR. DNA sequences were deposited in GenBank. Conclusion: Both Ae. albopictus e Ae. aegypti harbor Ascogregarina sp.

Evaluation of arboviruses of public health interest in free-living non-human primates (Alouatta spp., Callithrix spp., Sapajus spp.) in Brazil.

INTRODUCTION: The aim of the present study was to evaluate the presence of arboviruses from the Flavivirus genus in asymptomatic free-living non-human primates (NHPs) living in close contact with humans and vectors in the States of Paraná and Mato Grosso do Sul, Brazil. METHODS: NHP sera samples (total n = 80, Alouatta spp. n = 07, Callithrix spp. n = 29 and Sapajus spp. n = 44) were screened for the presence of viral genomes using reverse transcription polymerase chain reaction and 10% polyacrylamide gel electrophoresis techniques. RESULTS: All of the samples were negative for the Flavivirus genome following the 10% polyacrylamide gel electrophoresis analysis. CONCLUSIONS: These negative results indicate that the analyzed animals were not infected with arboviruses from the Flavivirus genus and did not represent a risk for viral transmission through vectors during the period in which the samples were collected.

Evaluation of arboviruses of public health interest in free-living non-human primates (Alouatta spp., Callithrix spp., Sapajus spp.) in Brazil

INTRODUCTION: The aim of the present study was to evaluate the presence of arboviruses from the Flavivirus genus in asymptomatic free-living non-human primates (NHPs) living in close contact with humans and vectors in the States of Paraná and Mato Grosso do Sul, Brazil. METHODS: NHP sera samples (total n = 80, Alouatta spp. n = 07, Callithrix spp. n = 29 and Sapajus spp. n = 44) were screened for the presence of viral genomes using reverse transcription polymerase chain reaction and 10% polyacrylamide gel electrophoresis techniques. RESULTS: All of the samples were negative for the Flavivirus genome following the 10% polyacrylamide gel electrophoresis analysis. CONCLUSIONS: These negative results indicate that the analyzed animals were not infected with arboviruses from the Flavivirus genus and did not represent a risk for viral transmission through vectors during the period in which the samples were collected. .

Aedes aegypti and Aedes albopictus (Diptera: Culicidae): coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization / Aedes aegypti e Aedes albopictus (Diptera: Culicidae): coexistência e susceptibilidade ao temephos, em municípios com ocorrência de casos de dengue e diferentes características de urbanização

INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion). Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina) presented survival when exposed to the organophosphate temephos.

INTRODUÇÃO: O presente estudo teve como objetivo verificar a coexistência de populações de Aedes aegypti e de Aedes albopictus em municípios do Estado do Paraná e Santa Catarina com diferentes formas de urbanização, onde ocorrem casos de dengue, e avaliar a susceptibilidade ao organofosforado temephos. MÉTODOS: O número de ovos por ovitrampa foram contados (sem distinguir a espécie) e colocados para eclosão e posterior identificação das espécies. A análise das populacões foi conduzida para determinar aleatoriedade e agregação usando a razão variância/média (índice de dispersão). A susceptibilidade ao temephos foi avaliada para determinar e estimar as razões de resistência RR50 e RR95. As amostras de Aedes aegypti, obtidas do Estado do Paraná, foram comparadas com a população Rockefeller e as amostras de Aedes albopictus foram comparadas com a população do Estado de Santa Catarina. RESULTADOS: Coexistência entre Aedes aegypti e Aedes albopictus, e a agregação de seus ovos foram observados em todos os locais analisados. CONCLUSÕES: Todas as populações de Aedes aegypti do Estado do Paraná demonstraram alteração no status de susceptibilidade ao organofosforado temephos, evidenciando resistência incipiente. Assim como, todas as populacões de Aedes albopictus avaliadas, do Estado do Paraná e Santa Catarina, apresentaram sobrevivência quando expostas ao organofosforado temefós.

Aedes aegypti and Aedes albopictus (Diptera: Culicidae): coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization.

INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion). Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina) presented survival when exposed to the organophosphate temephos.

Lista das espécies de Culicidae (Diptera) depositadas na Coleção de Entomologia Pe. J. S. Moure / Species list of the Culicidae (Diptera) deposited at the Entomological Collection \"Pe. J. S. Moure\"

A Coleção de Entomologia do Departamento de Zoologia da Universidade Federal do Paraná (DZUP) abriga cerca de 5.000.000 de exemplares de insetos. A coleção de Diptera está representada por aproximadamente 2.000.000 de exemplares, sendo Muscidae; Culicidae e Syrphidae as famílias mais representativas. A ordem Diptera possui cerca de 150.000 espécies descritas e a coleção conta com cerca de 103.000 exemplares representantes de 78 famílias. A lista das espécies pertencentes à família Culicidae conta com 9.579 exemplares, distribuídos em 2 subfamílias, 7 tribos, 17 gêneros, 26 subgêneros e 85 espécies. A maioria dos exemplares foi coletado em remanescentes de mata localizados em áreas urbanas e rurais, ambientes silvestres e urbanos de regiões litorâneas ou áreas urbanas pertencentes a diferentes cidades do Estado do Paraná, e algumas espécies incluídas foram capturadas nos Estados de São Paulo, Mato Grosso, Santa Catarina e no Distrito Federal. As informações específicas de cada exemplar, como local de coleta, latitude, longitude, coletor, data de coleta, método de coleta e nome do pesquisador que identificou, e também informações taxonômicas como ordem, tribo, gênero, subgênero e espécie, foram informatizados em um banco de dados.

The Entomological Collection of Departamento de Zoologia of Universidade Federal do Paraná (DZUP) accommodates about 5,000,000 insect specimens. The collection of Diptera is represented by approximately 2,000,000 specimens, being Muscidae, Culicidae and Syrphidae the most representative families. The Diptera order consists of approximately 150,000 described species and in the Collection about 103,000 specimens within 78 families are registered. The list of species of the family Culicidae presents 9,579 specimens within 2 subfamilies, 7 tribes, 17 genera, 26 subgenera and 85 species. Most specimens were captured in forest remnants in urban and rural areas, wild and urban environments in coastal regions or urban areas of different cities of Paraná State, including some species captured in the States of São Paulo, Mato Grosso and Santa Catarina and at Distrito Federal. The specific information of each specimen, such as collection site, latitude, longitude, collector, collection date, collection method and the specialist's name who identified it, as well as taxonomic data (order, tribe, genus, subgenus and species), was included in a electronic data base.

[Evaluation of the temperature influence on the development of Aedes albopictus]. / Avaliação da influência da temperatura sobre o desenvolvimento de Aedes albopictus.

OBJECTIVE: To verify the temperature's influence on the Aedes albopictus development stages under laboratory conditions. METHODS: The development period of eggs, larvae and pupas were assessed at constant temperatures, 15 degrees C, 20 degrees C, 25 degrees C and 30 degrees C, inside acclimatized chambers with 70-85% of relative humidity, and LD 12:12 h. The effect of the four constant temperatures was assessed using variance analysis. RESULTS: The incubation periods of eggs were 38.38, 19.09, 13.10, and 10.44 days. Larval periods for males lasted 30.13, 13.83, 7.36, and 5.57 days; for females it lasted 33.22, 15.00, 8.06, and 6.16 days. Pupil period for males lasted 8.01, 4.92, 2.40, and 1.76 days; and for females it lasted 8.15, 5.11, 2.60, and 1.88 days under the temperatures of 15 degrees C, 20 degrees C, 25 degrees C and 30 degrees C, respectively. In all development stages for all temperatures, significant differences were found at the level of 5%. The development period was inversely associated to the temperature, and the larval period was shorter in males than in females. Under the temperatures of 20 degrees C and 30 degrees C, the development of immature stages was shorter and their viability was greater than at 15 degrees C. CONCLUSIONS: In the conditions the experiment was performed, the temperature affected significantly and inversely proportional Aedes albopictus immature stages. These results show that immature stages are more susceptible at low temperatures due to the longer time required completing their development. This could be used in vector control strategies.

Avaliaçäo da influência da temperatura sobre o desenvolvimento de Aedes albopictus / Evaluation of the temperature influence on the development of Aedes albopictus

OBJETIVO: Verificar a influência da temperatura sobre os estágios de desenvolvimento de Aedes albopictus sob condiçöes de laboratório. MÉTODOS: Foi avaliado o período de desenvolvimento dos estágios de ovo, larva e pupa em quatro temperaturas constantes de 15§C, 20§C, 25§C e 30§C em câmaras climatizadas com umidade relativa do ar oscilando entre 70por cento e 85por cento e fotoperíodo de CE 12:12 horas. Pela análise de variância, foram testados os efeitos das quatro temperaturas constantes. RESULTADOS: O período de incubaçäo dos ovos compreendeu 38,38; 19,09; 13,10; e 10,44 dias; o período larval dos indivíduos machos atingiu 30,13; 13,83; 7,36; e 5,57 dias; o período larval para fêmeas apresentou duraçäo de 33,22; 15,00; 8,06; e 6,16 dias; o período pupal em machos compreendeu 8,01; 4,92; 2,40; e 1,76 dias, enquanto nas fêmeas foi de 8,15; 5,11; 2,60; e 1,88 dias sob as temperaturas de 15§C, 20§C, 25§C e 30§C, respectivamente. Em todos os estágios de desenvolvimento, foram encontradas diferenças significativas, entre as temperaturas avaliadas, em torno de 5por cento no tempo de desenvolvimento. O período de desenvolvimento foi inversamente relacionado à temperatura, com o período larval mais breve em machos que em fêmeas. Nas temperaturas de 20§C a 30§C, o desenvolvimento foi mais breve e com maior viabilidade que a 15§C. CONCLUSOES: Nas condiçöes em que foram realizados os experimentos, a temperatura afetou de forma significativa e inversamente proporcional os estágios imaturos de Aedes albopictus. Esses resultados mostram que os estágios imaturos säo mais suscetíveis durante os períodos de baixas temperaturas devido ao maior tempo necessário para completar o desenvolvimento, informaçäo que pode ser utilizada em estratégias de controle