Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
1.
Mem. Inst. Oswaldo Cruz ; 115: e200046, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135261

ABSTRACT

BACKGROUND Fluctuations in climate have been associated with variations in mosquito abundance. OBJECTIVES To analyse the influence of precipitation, temperature, solar radiation, wind speed and humidity on the oviposition dynamics of Aedes aegypti in three distinct environmental areas (Brasília Teimosa, Morro da Conceição/Alto José do Pinho and Dois Irmãos/Pintos) of the city of Recife and the Fernando de Noronha Archipelago northeastern Brazil. METHODS Time series study using a database of studies previously carried out in the areas. The eggs were collected using spatially distributed geo-referenced sentinel ovitraps (S-OVTs). Meteorological satellite data were obtained from the IRI climate data library. The association between meteorological variables and egg abundance was analysed using autoregressive models. FINDINGS Precipitation was positively associated with egg abundance in three of the four study areas with a lag of one month. Higher humidity (β = 45.7; 95% CI: 26.3 - 65.0) and lower wind speed (β = −125.2; 95% CI: −198.8 - −51.6) were associated with the average number of eggs in the hill area. MAIN CONCLUSIONS The effect of climate variables on oviposition varied according to local environmental conditions. Precipitation was a main predictor of egg abundance in the study settings.


Subject(s)
Animals , Female , Oviposition/physiology , Aedes/physiology , Population , Seasons , Brazil , Population Dynamics , Cities , Mosquito Vectors/physiology
2.
Mem. Inst. Oswaldo Cruz ; 115: e190437, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135272

ABSTRACT

BACKGROUND Aedes aegypti and Aedes albopictus are the most important arbovirus vectors in the world. OBJECTIVES This study aimed to investigate and compare the infestation pattern of these species in a neighbourhood of Recife, Brazil, endemic for arboviruses in 2005 (T1) and 2013 (T2). METHODS Infestation, distribution and relative abundance of these sympatric species were recorded by egg collection using a network of 59 sentinel ovitraps (s-ovt) at fixed sampling stations for 12 months in T1 and T2. FINDINGS A permanent occupation pattern was detected which was characterised by the presence of egg-laying females of one or both species with a high ovitrap positivity index (94.3 to 100%) throughout both years analysed. In terms of abundance, the total of eggs collected was lower (p < 0.005) in T2 (146,153) than in T1 (281,103), although ovitraps still displayed a high index of positivity. The spatial distribution showed the presence of both species in 65.1% of the 148 s-ovt assessed, while a smaller number of traps exclusively contained Ae. aegypti (22%) or Ae. albopictus (13.2%) eggs. MAIN CONCLUSIONS Our comparative analysis demonstrated the robustness of the spatial occupation and permanence of Ae. aegypti and Ae. albopictus populations in this endemic urban area.


Subject(s)
Animals , Male , Female , Aedes/classification , Mosquito Vectors/classification , Oviposition , Arbovirus Infections/transmission , Arbovirus Infections/epidemiology , Seasons , Brazil/epidemiology , Population Density , Endemic Diseases , Aedes/physiology , Animal Distribution , Mosquito Vectors/physiology
3.
Mem. Inst. Oswaldo Cruz ; 115: e190390, 2020. tab, graf
Article in English | LILACS | ID: biblio-1056771

ABSTRACT

The mosquito Culex pipiens s.s. L. occurs as two bioforms that differ in physiology and behaviour affecting virus transmission cycles. To assess the occurrence of Cx. pipiens bioforms in the southernmost limit of its distribution, specimens were collected aboveground in southern Buenos Aires Province and east Patagonia, Argentina. Ten larvae and 25 adults were individually processed and identified by polymerase chain reaction (PCR) amplification of Ace-2 and CQ11 loci. Culex quinquefasciatus Say (one larva, two adults), Cx. pipiens f. molestus (one larva, one adult) and one adult of hybrid origin were identified in Buenos Aires Province; only Cx. pipiens f. molestus was recorded in Patagonia (eight larvae, 21 adults). The potential absence of bioform pipiens and its implications in arbovirus enzootic cycles is discussed.


Subject(s)
Animals , Culex/physiology , Mosquito Vectors/physiology , Argentina , Seasons , Polymerase Chain Reaction , Culex/genetics , Culex/virology , Encephalitis, St. Louis/transmission , Animal Distribution , Mosquito Vectors/genetics , Mosquito Vectors/virology
4.
Rev. Soc. Bras. Med. Trop ; 53: e20190277, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057296

ABSTRACT

Abstract INTRODUCTION: This study aimed to assess the occurrence of gonotrophic discordance in females of Culex quinquefasciatus in São Paulo, Brazil. METHODS: Resting females were collected monthly for 8 months. Females of Cx. quinquefasciatus were identified, and their midgut and ovaries were dissected. RESULTS: Two hundred females were dissected, out of which, 27.5% were nulliparous and 57% were parous. Most females had no blood in the midgut, but gonotrophic discordance was found in 21% females. CONCLUSIONS: Females of Cx. quinquefasciatus showed a high parity rate and gonotrophic discordance, which could favor the vector capacity of this species.


Subject(s)
Animals , Male , Female , Culex/physiology , Mosquito Vectors/physiology , Reproduction/physiology , Elephantiasis, Filarial/transmission , Brazil , Culex/classification , Dirofilariasis/transmission , Oviparity/physiology , Feeding Behavior/physiology , Mosquito Vectors/classification , Longevity/physiology
5.
Rev. Soc. Bras. Med. Trop ; 53: e20190504, 2020. tab, graf
Article in English | LILACS | ID: biblio-1101440

ABSTRACT

Abstract INTRODUCTION: The study of the landscape ecology, biological microhabitat, and epidemiological implications for the distribution of the main vectors Aedes aegypti and Aedes albopictus contribute to the prevention and control actions regarding the diseases they transmit. METHODS: This study sought to assess data on positive properties of the vector control program activities from 1998 to 2010. An entomological survey was also carried out on a sample of buildings collecting larvae and pupae from containers between October and April (spring / summer) from 2002 to 2005. We assessed the physico-chemical data of the water in 20% of positive containers. The vegetation and urbanization were assessed with the aid of satellite images and microenvironments were classified as urbanized, woods, and shrubs. The data were analyzed using statistical and geoprocessing software. RESULTS: Ae. aegypti and Ae. albopictus colonized all types of microhabitats and microenvironments, predominantly in the urbanized area, in isolation and in coexistence. The microhabitat of Ae. aegypti showed a temperature gradient greater than that of Ae. albopictus, and there was an association with urbanized areas for the first species and wooded areas for the last species. CONCLUSIONS: Landscape ecology and intra-urban differences favor different microclimates, which contribute to the coexistence of species in the urban environment in an area close to the forest, raising the risk of other arbovirus infections in urban areas. The ecological niche should be considered for Ae. albopictus. Entomological and virologic monitoring are suggested as arbovirus surveillance actions in urban infested centers near preserved forests.


Subject(s)
Animals , Ecosystem , Aedes/physiology , Mosquito Vectors/physiology , Arbovirus Infections/transmission , Seasons , Urban Population , Brazil , Population Density , Aedes/classification , Spatial Analysis , Animal Distribution , Mosquito Vectors/classification
6.
Rev. Soc. Bras. Med. Trop ; 53: e20190185, 2020. graf
Article in English | LILACS | ID: biblio-1092198

ABSTRACT

Abstract INTRODUCTION: Aedes aegypti and Culex quinquefasciatus are vector species responsible for the transmission of important arboviruses. METHODS: Adult mosquitoes were collected in the urban areas of four municipalities in Mato Grosso within 1 year. RESULTS: A total of 19,110 mosquitoes were collected. Among them, 16,578 (86,8%) were C. quinquefasciatus (44% female and 56% male); 2,483 (13%), A. (Stegomyia) aegypti (54% female and 46% male); and 49 (0,30%), from the genus Psorophora, Anopheles, Coquilettidia, and Sabethes. A significant correlation was observed between the number of mosquitoes from all species and dew point (female mosquitoes, p = 0.001; male mosquitoes, p = 0.001). CONCLUSIONS: The results of this study may be used as environmental indicators of mosquito populations.


Subject(s)
Animals , Male , Female , Climate , Aedes/physiology , Culex/physiology , Mosquito Vectors/physiology , Urban Population , Brazil
7.
Clinics ; 74: e675, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019708

ABSTRACT

The present study aimed to review literature on studies of dengue cases conducted over 30 years in the state of Ceará. Between November 2015 and January 2016, articles published in Portuguese and English in 7 databases were searched using keywords and a Boolean operator. A total of 191 articles were identified in the databases; 133 were excluded according to the exclusion criteria, and 58 were included in the study. Of the 58 articles analyzed, 6 reported data from Brazil; including the Northeast region and the state of Ceará; 41 reported data for only the city of Fortaleza; 7 reported data for the state of Ceará; 4 reported data for cities in the interior of the state; and 3 included only children. The studies adopted different approaches and focused on different aspects of the disease. Study outcomes included the identification of serological, epidemiological, clinical, and laboratory characteristics; potential larvicides and biological predators of mosquitoes; potential antiviral agents; vector density characteristics; and educational dengue prevention and control strategies. Additionally, one vaccine trial was included. Although studies on dengue in the state of Ceará are scarce, they are encompassing, including several lines of research, and the number of studies and reports on dengue in the state of Ceará continues to increase.


Subject(s)
Humans , Animals , Endemic Diseases/statistics & numerical data , Aedes/classification , Dengue/epidemiology , Mosquito Vectors/physiology , Predatory Behavior , Research Design , Species Specificity , Brazil/epidemiology , Endemic Diseases/prevention & control , Aedes/physiology , Dengue/prevention & control , Dengue/transmission
8.
Rev. Soc. Bras. Med. Trop ; 52: e20180341, 2019. graf
Article in English | LILACS | ID: biblio-1041576

ABSTRACT

Abstract INTRODUCTION: Areas at risk of transmission of arboviruses have been monitored using ovitraps. This study aimed to evaluate the spatial distribution of Aedes aegypti in vulnerable areas for the transmission of arboviruses and assess the influence of climatic conditions on the infestation of these culicids. METHODS: Ovitraps were installed in Agrestina, Pernambuco, Northeastern Brazil. RESULTS: Overall, 44,936 eggs were collected, and the indexes of infestation varied. Relative humidity was significantly associated with the infestations. CONCLUSIONS: Using ovitraps, entomologic indexes and analysis of climatic factors might be good strategies for monitoring vulnerable areas for the transmission of arboviruses.


Subject(s)
Humans , Animals , Oviposition , Mosquito Control/methods , Dengue/prevention & control , Flavivirus , Chikungunya Fever/prevention & control , Zika Virus Infection/prevention & control , Rain , Seasons , Temperature , Brazil , Residence Characteristics , Aedes/physiology , Dengue/transmission , Spatial Analysis , Chikungunya Fever/transmission , Zika Virus Infection/transmission , Mosquito Vectors/physiology , Humidity
9.
Rev. Soc. Bras. Med. Trop ; 52: e20190159, 2019. graf
Article in English | LILACS | ID: biblio-1041542

ABSTRACT

Abstract INTRODUCTION: The lack of highly-productive Nyssorhynchus darlingi laboratory colonies limits some studies. We report the first well-established laboratory colony of Ny. darlingi in Brazil. METHODS: Mosquitoes were collected from Porto Velho and were reared at the Laboratory of Fiocruz/RO. After induced mating by light stimulation in the F1 to F6, the subsequent generations were free mating. Larvae were reared in distilled water and fed daily until pupation. RESULTS: In 11 generations, the colony produced a high number of pupae after the F5 generation. CONCLUSIONS: These results demonstrate the potential for permanently establishing Ny. darlingi colonies for research purposes in Brazil.


Subject(s)
Animals , Mosquito Vectors/growth & development , Anopheles/growth & development , Oviposition , Reproduction , Brazil , Mosquito Vectors/physiology , Malaria , Anopheles/physiology
10.
Cad. Saúde Pública (Online) ; 34(5): e00078017, 2018. tab
Article in Portuguese | LILACS | ID: biblio-952385

ABSTRACT

Resumo: Devido à persistência da dengue e de outras arboviroses no Brasil, o poder público tem intensificado as ações de combate ao mosquito vetor Aedes aegypti. Os agentes de combate às endemias (ACE) e agentes comunitários de saúde (ACS), dentre outras atribuições, tornaram-se interlocutores e disseminadores de conhecimento na comunidade. O objetivo deste trabalho foi analisar os saberes e práticas sobre controle da dengue por diferentes sujeitos sociais: moradores e agentes. Foram realizadas entrevistas com moradores, ACE de campo e de mobilização e ACS em dois bairros de Salvador, Bahia, por meio da metodologia de grupo focal. Os moradores demonstraram incerteza sobre a forma de contágio e o perigo da dengue. Os ACE de campo apresentam-se em conflito, pela necessidade de informar à comunidade sobre aspectos que não dominam e demonstram um descontentamento pessoal no trabalho com um sentimento de desvalorização pela falta de qualificação. Os ACE de mobilização culpam a população e enfatizam a importância de si próprios como solução para o controle da dengue. Os ACS não apropriaram sua experiência de campo em seu discurso e se sentem desobrigados com respeito ao controle vetorial. Todos os grupos entrevistados concordam que a culpa da dengue recai sobre o poder público, e a solução para o problema está na educação. Percebe-se uma grande necessidade de intervenções educativas regulares, pautadas no diálogo e na sensibilização para lidar com a realidade cotidiana dos moradores, trazendo os indivíduos (moradores e agentes) como sujeitos do processo de construção de conhecimento. Pois, na metodologia atual, a disseminação de informação e conhecimento não é suficiente para promover melhorias na comunidade para o controle da dengue.


Abstract: Due to the persistence of dengue and other arbovirus infections in Brazil, the government has stepped up measures to combat the Aedes aegypti mosquito vector. The responsibilities of community endemic disease workers (CEDW) and community health workers (CHW) include acting as intermediaries and disseminating knowledge in the community. The aim of this study was to analyze knowledge and practices in dengue control by different social subjects: residents and CEDW/CHW. Interviews were held with residents, field and mobilization CEDW, and CHW in two neighborhoods in Salvador, Bahia State, using focus groups. Residents expressed uncertainty on the form of transmission and hazards of dengue. Field CEDW voiced conflicting feelings due to the need to inform the community on issues over which they lack any control, while expressing personal dissatisfaction with their work and a feeling of underappreciation due to their lack of training. Mobilization CEDW blamed the population and emphasized their own importance as the solution to dengue control. CHW failed to reflect their field experience in their discourse and felt they had no responsibility over vector control. All the groups agreed that government is to blame for dengue and that the solution lies in education. There is an evident need for regular educational interventions, based on dialogue and awareness-raising to deal with residents' daily reality, drawing individuals (residents and CHW) into the knowledge-building process. Under the prevailing methodology, the dissemination of information and knowledge is insufficient to promote community improvements for dengue control.


Resumen: Debido a la persistencia del dengue y de otras arbovirosis en Brasil, el poder público ha intensificado las acciones de combate al mosquito vector Aedes aegypti. Los ACE (agentes de combate a endemias) y los ACS (agentes comunitarios de salud), entre otras atribuciones, se convirtieron en interlocutores y promotores de conocimiento sobre enfermedades en sus comunidades. El objetivo de este trabajo fue analizar los conocimientos y prácticas sobre el control del dengue por parte de los diferentes sujetos sociales implicados: residentes y agentes. Se realizaron entrevistas a residentes, ACE de campo y de movilización, así como ACS, en dos barrios de Salvador, Bahía, mediante una metodología de grupo focal. Los residentes mostraron inseguridad sobre la forma de contagio, así como el peligro que supone el dengue. Los ACE de campo se encontraron en conflicto, por su necesidad de informar a la comunidad sobre aspectos que no dominan, además de demostrar un descontento personal en el trabajo, unido a un sentimiento de desvalorización, por su falta de cualificación. Los ACE de movilización culpan a la población y enfatizan la importancia de ellos mismos como solución para el control del dengue. Los ACS no se apropiaron de su experiencia de campo en su discurso y no se sienten obligados al control vectorial. Todos los grupos entrevistados concuerdan en que la culpa del dengue recae sobre el poder público, y la solución para el problema está en la educación. Se percibe una gran necesidad de intervenciones educativas regulares, pautadas en el diálogo y en la sensibilización para lidiar con la realidad cotidiana de los residentes, considerando a los individuos (residentes y agentes) como sujetos del proceso de construcción del conocimiento. Así pues, en la metodología actual, la divulgación de información y conocimiento no es suficiente para promover mejoras en las comunidades, con el fin de controlar el dengue.


Subject(s)
Humans , Animals , Male , Female , Adult , Middle Aged , Aged , Young Adult , Health Knowledge, Attitudes, Practice , Mosquito Control/methods , Aedes/physiology , Dengue/prevention & control , Mosquito Vectors/physiology , Brazil , Focus Groups , Community Participation
11.
Rev. chil. infectol ; 34(6): 553-556, dic. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-899758

ABSTRACT

Resumen El virus Zika ha despertado una alarma mundial en los últimos años, representando un problema importante para la salud pública. En este estudio evaluamos el riesgo potencial de exposición a virus Zika en Chile, asociado a la probabilidad de establecimiento del vector Aedes aegypti en el país. Se utilizaron técnicas de modelación de nicho para proyectar los requerimientos bioclimáticos del vector (nicho global), identificando las zonas de alta idoneidad para la especie en el país. Luego, se superpuso la distribución potencial del vector en Chile con la densidad de población humana, estimando en forma espacialmente explícita el riesgo asociado a la co-ocurrencia potencial de ambos. Identificamos que existe idoneidad bioclimática para A. aegypti en Chile continental, desde el área tropical del norte hasta regiones templadas, principalmente en zonas costeras. La población potencialmente expuesta podría alcanzar 1,8 millones de personas, con 1,3 millones en nivel medio y 21.000 en niveles altos de riesgo potencial de exposición. Los resultados expuestos aquí muestran que existe una significativa probabilidad de éxito de colonización del vector principal de virus Zika en Chile continental en caso de una introducción. Por lo tanto, la prevención, monitoreo y control se vuelven un tema importante para evitar la llegada de este vector a Chile continental.


The Zika virus has raised world alarm in recent years, representing a major public health problem. In this study we evaluated the potential risk of exposure to Zika virus in Chile, associated with the probability of establishment of the vector Aedes aegypti in the country. Niche modelling techniques were used to project the bioclimatic requirements of the vector (global niches), identifying zones of high suitability for the species within the country. Then, the potential distribution of the vector in Chile was overlapped with the human population density, estimating the risk associated to the potential co-occurrence of both in a spatially explicit manner. We identified bioclimatic suitability for A. aegypti in continental Chile, from the northern tropical area to temperate regions, mainly in coastal zones. The exposed population could reach 1.8 million people, with 1.3 million in a medium level of potential risk and 21,000 in a high level. These results support that there is a significant probability of success for the Zika virus main vector to colonize continental Chile in case of an introduction. Therefore, prevention, monitoring, and control play an important role in avoiding the arrival of this vector to our country.


Subject(s)
Animals , Aedes/physiology , Aedes/virology , Zika Virus , Zika Virus Infection/transmission , Mosquito Vectors/physiology , Mosquito Vectors/virology , Chile , Risk Factors , Population Density , Ecosystem , Risk Assessment/methods , Environmental Exposure/statistics & numerical data , Animal Distribution
12.
Biomédica (Bogotá) ; 37(supl.2): 201-207, jul.-set. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-1038793

ABSTRACT

Resumen Introducción. Riohacha, capital del departamento de La Guajira, registra las tasas más altas de malaria o paludismo en el departamento, especialmente entre los indígenas de la etnia wayúu. Objetivo. Describir algunos aspectos de la bionomía de las especies del género Anopheles presentes en dos rancherías de la etnia wayúu. Materiales y métodos. Se hicieron dos muestreos durante las temporadas de lluvia y sequía en las rancherías Marbacella y El Horno (municipio de Riohacha, La Guajira). Se recolectaron formas inmaduras de los mosquitos y se describieron sus hábitats. Los mosquitos adultos se recolectaron al posarse en sujetos humanos, previo consentimiento informado, y con trampas de luz Shannon y CDC. Resultados. Todos los ejemplares recolectados eran Anopheles albimanus, especie que registró actividad de picadura durante toda la noche en el peridomicilio (n=7), en tanto que en el intradomicilio se capturaron solo dos mosquitos entre las 18:00 y las 20:00 horas. Los sitios de cría positivos correspondieron a jagüeyes (n=7; 38,8 %), charcos (n=2; 10,5 %), y estanques piscícolas (n=2; 10,5 %). La mayor abundancia de formas inmaduras se encontró en los jagüeyes (n=25; 78 %), cuyo pH oscilaba entre 7,20 y 7,81 a una temperatura de 26,5 °C, y se localizaban a 150 m de distancia de las viviendas. Conclusión. Anopheles albimanus se registró en todos los depósitos de agua de ambas rancherías. Dado que la especie se considera vector primario de la malaria en la zona, debe establecerse un sistema de vigilancia entomológica local que involucre a la comunidad a la vez que respete su cosmología y actividades rutinarias como la pesca.


Abstract Introduction: Riohacha, capital of the department of La Guajira, reports the highest rates for malaria in the department, and the most vulnerable people are those of the Wayúu indigenous group. Objective: To describe some aspects of the bionomics of the Anopheles species in two Wayúu settlements. Materials and methods: Two sampling events were carried out during dry and rainy seasons in Marbacella and El Horno (Riohacha, La Guajira). Immature stages of Anopheles spp. were collected, and breeding sites were described. Adult mosquitoes were collected with human landing catches, Shannon traps and CDC traps. Results: All collected specimens were Anopheles albimanus. Biting activity occurred outdoors during all the night (n=7), while indoors, only two mosquitoes were captured between 18:00 and 20:00 hours. The positive breeding sites corresponded to jagüeyes (n=7, 38.8%), pools (n=2, 10.5%), and fishponds n=2, 10.5%). The highest abundance of immature forms was found in the jagüeyes (n=25, 78%), which had pH values between 7.20 and 7.81 and a temperature of 25°C, and were located 150 m away from Wayúu homes. Conclusion: Anopheles albimanus was the only collected species found in water supply deposits in the villages Marbacella and El Horno. Given that the species is the main vector for malaria in the area, we suggest the implementation of a community-based entomological surveillance system which should respect Wayúu cosmology and routine activities such as fishing.


Subject(s)
Animals , Female , Humans , Mosquito Vectors/physiology , Anopheles/physiology , Rain , Rural Population , Seasons , Temperature , Water Supply , Ethnicity , Indians, South American , Colombia , Droughts , Feeding Behavior , Mosquito Vectors/parasitology , Hydrogen-Ion Concentration , Malaria/transmission , Malaria/epidemiology , Anopheles/parasitology
13.
Biomédica (Bogotá) ; 37(supl.2): 59-66, jul.-set. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-888525

ABSTRACT

Resumen Introducción. La distribución espacial de Aedes aegypti es heterogénea, y la interacción entre criaderos positivos y potenciales en el intradomicilio y el extradomicilio es uno de los aspectos más difíciles de caracterizar en los programas de control vectorial. Objetivo. Describir la relación espacial entre los criaderos potenciales y positivos de A. aegypti en el intradomicilio y en el extradomicilio en un sector de Cali, Colombia. Materiales y métodos. Se hizo una encuesta entomológica con el objetivo de recolectar datos de los criaderos en el intradomicilio y el extradomicilio. El análisis exploratorio de los datos espaciales incluyó la localización, la tendencia espacial, la autocorrelación espacial local, la continuidad espacial y la correlación espacial de los criaderos positivos y potenciales según el hábitat. Resultados. Se determinaron las tendencias espaciales. Mediante el análisis de autocorrelación espacial local se ubicaron los conglomerados de criaderos potenciales y positivos del extradomicilio. Se encontró una correlación positiva entre los criaderos potenciales y los positivos y una correlación negativa entre el intradomicilio y el extradomicilio. Conclusiones. La relación espacial entre criaderos positivos y potenciales de A. aegypti en el intradomicilio y el extradomicilio es dinámica y muy sensible a las características de cada territorio, por lo que establecer su distribución en el espacio contribuye a la priorización de recursos y acciones en los programas de control vectorial.


Abstract Introduction: The spatial distribution of Aedes aegypti is heterogeneous, and the interaction between positive and potential breeding sites located both inside and outside homes is one of the most difficult aspects to characterize in vector control programs. Objective: To describe the spatial relationship between potential and positive breeding sites of A. aegypti inside and outside homes in Cali, Colombia. Materials and methods: We conducted an entomological survey to collect data from both indoor and outdoor breeding sites. The exploratory analysis of spatial data included location, spatial trends, local spatial autocorrelation, spatial continuity and spatial correlation of positive and potential breeding sites according to habitat. Results: Spatial trends were identified, as well as clusters of potential and positive breeding sites outdoors using local spatial autocorrelation analysis. A positive correlation was found between potential and positive breeding sites, and a negative correlation existed between indoor and outdoor sites. Conclusions: The spatial relationship between positive and potential A. aegypti breeding sites both indoors and outdoors is dynamic and highly sensitive to the characteristics of each territory. Knowing how positive and potential breeding sites are distributed contributes to the prioritization of resources and actions in vector control programs.


Subject(s)
Animals , Disease Reservoirs , Aedes , Mosquito Vectors , Reproduction , Colombia , Aedes/physiology , Animal Distribution , Geography, Medical , Mosquito Vectors/physiology , Housing
14.
Biomédica (Bogotá) ; 37(supl.2): 98-105, jul.-set. 2017. tab, graf
Article in English | LILACS | ID: biblio-888529

ABSTRACT

Abstract Introduction: In Colombia there are three Anopheles species implicated in malaria transmission as primary vectors; however, the local role of some Anopheles species must still be defined. Objective: To determine the abundance, composition and natural infection rates for Anopheles mosquitoes with Plasmodium spp. in two malaria-endemic regions of Colombia. Materials and methods: Anopheles mosquitoes were collected using the human-landing catches and while resting in livestock corrals in nine localities of two malaria-endemic regions of Colombia. Mosquitoes were morphologically identified and confirmed by PCR-RFLP-ITS2. Identified mosquitoes were processed and tested for Plasmodium parasite infection by ELISA and ssrRNA-based nested PCR. Results: We collected 1,963 Anopheles mosquitoes corresponding to nine species. The most abundant species were Anopheles nuneztovari (53.5%) and A. darlingi (34.5%), followed by A. triannulatus s.l. (6%), and other species (˜5.9%). Three species were naturally infected with Plasmodium spp.: A. darlingi, A. nuneztovari and A. triannulatus s.l. Conclusions: Natural infection of A. darlingi and A. nuneztovari indicate that these malaria vectors continue to be effective carriers of Plasmodium in the localities under study in Valle del Cauca and Chocó. Additionally, the infected A. triannulatus s.l. collected in livestock corrals in the locality of the department of Córdoba suggests the need for further studies to define the epidemiological importance of this species given its abundance and opportunistic anthropophilic behavior.


Resumen Introducción. En Colombia hay tres especies de mosquitos Anopheles implicadas como vectores primarios en la transmisión de la malaria o paludismo; sin embargo, el rol local de algunas especies de Anopheles aún debe determinarse. Objetivo. Determinar la abundancia, la composición y la infección natural de mosquitos anofelinos con Plasmodium spp. en dos regiones endémicas de malaria en Colombia. Materiales y métodos. Se recolectaron mosquitos del género Anopheles usando los métodos de recolección con cebo humano y en reposo en corrales de ganado vacuno, en nueve localidades de dos regiones endémicas para malaria en Colombia. Los especímenes se identificaron morfológicamente y se confirmaron por reacción en cadena de la polimerasa (PCR) de los polimorfismos en la longitud de los fragmentos de restricción (Restriction Fragment Length Polymorphism, RFLP) en el espaciador intergénico ribosómico nuclear 2 (Internal Transcribed Spacer, ITS-2) (PCR-RFLPITS2). Los especímenes se procesaron y analizaron mediante ELISA y PCR anidada basada en la subunidad pequeña del ARN ribosómico (small subunit ribosomal RNA, ssrRNA) para determinar la infección por Plasmodium. Resultados. Se recolectaron 1.963 mosquitos Anopheles correspondientes a nueve especies. Anopheles nuneztovari fue la especie predominante (53,5 %), seguida por A. darlingi (34,5 %), A. triannulatus s.l. (6 %) y por otras especies (˜5,9 %). Tres especies se encontraron naturalmente infectadas con Plasmodium spp.: A. darlingi, A. nuneztovari y A. triannulatus s.l. Conclusiones. La infección natural de A. darlingi y A. nuneztovari indica que estos vectores primarios siguen siendo actores principales en la transmisión de malaria en las localidades estudiadas de los departamentos del Valle del Cauca y Chocó. Además, el espécimen A. triannulatus s.l. infectado, recolectado en corrales de animales de la localidad estudiada en el departamento de Córdoba, indica que existe la necesidad de estudios futuros para establecer la importancia epidemiológica de esta especie dada su abundancia y comportamiento antropofílico oportunista.


Subject(s)
Animals , Female , Humans , Plasmodium/isolation & purification , Endemic Diseases , Mosquito Vectors/parasitology , Malaria/transmission , Anopheles/parasitology , Species Specificity , Polymorphism, Restriction Fragment Length , DNA, Ribosomal/analysis , Polymerase Chain Reaction , DNA, Protozoan/analysis , Cities , Colombia/epidemiology , DNA, Ribosomal Spacer/analysis , Feeding Behavior , Geography, Medical , Mosquito Vectors/physiology , Malaria/epidemiology , Anopheles/physiology , Anopheles/genetics
16.
EMHJ-Eastern Mediterranean Health Journal. 2016; 22 (5): 350-355
in English | IMEMR | ID: emr-181489

ABSTRACT

Following the WHO declaration on 1 February 2016 of a Public Health Emergency of International Concern [PHEIC] with regard to clusters of microcephaly and neurological disorders potentially associated with Zika virus, the WHO Regional Office for the Eastern Mediterranean conducted three rounds of emergency meetings to address enhancing preparedness actions in the Region. The meetings provided up-to-date information on the current situation and agreed on a set of actions for the countries to undertake to enhance their preparedness and response capacities to Zika virus infection and its complications. The most urgent action is to enhance both epidemiological and entomological surveillance between now and the coming rainy seasons in countries with known presence of Aedes mosquitoes. Zika virus like other vector-borne diseases poses a particular challenge to the countries because of their complex nature which requires multidisciplinary competencies and strong rapid interaction among committed sectors. WHO is working closely with partners and countries to ensure the optimum support is provided to the countries to reduce the risk of this newly emerged health threat


Subject(s)
Humans , Zika Virus Infection/epidemiology , Aedes/pathogenicity , Mosquito Vectors/physiology
SELECTION OF CITATIONS
SEARCH DETAIL