Zika en silencio epidemiológico / Zika in epidemiological silence

La enfermedad por virus del Zika ha sufrido una importante disminución en la notificación de casos. A nivel mundial se observa un descenso aproximado del 58%, comparado con el mismo periodo en 2020. En México ocurre una situación similar, pues en la semana epidemiológica 48 solamente se han confirmado 34 casos. Dicha situación coincide con la pandemia por SARS-CoV-2, la cual se vive desde el 2019; sin embargo, es de suma importancia reestablecer las acciones de vigilancia epidemiológica enfocadas en el Zika para así continuar con las medidas de prevención y control dirigidas a minimizar el impacto de la enfermedad.

Zika virus disease has suffered a significant decrease in case reporting. Worldwide, an approximate decrease of 58% is observed, compared to the same period in 2020. Mexico is experiencing a similar situation, given that at epidemiological week 48 only 34 cases have been confirmed. This situation coincides with the SARS-CoV-2 pandemic, which has been experienced since 2019; however, it is of the utmost importance to reestablish epidemiological surveillance actions aimed at Zika to continue with prevention and control measures focused on minimizing the impact of the illness.

Protocolo Brasileiro para Infecções Sexualmente Transmissíveis 2020: infecção pelo vírus Zika / Brazilian Protocol for Sexually Transmitted Infections 2020: Zika virus infection / Protocolo Brasileño para Infecciones de Transmisión Sexual 2020: infección por el virus Zika

Este artigo aborda as transmissões vetorial, sexual e vertical do vírus Zika, tema contemplado no Protocolo Clínico e Diretrizes Terapêuticas para Atenção Integral às Pessoas com Infecções Sexualmente Transmissíveis, publicado pelo Ministério da Saúde do Brasil em 2020. Embora no Brasil o vírus Zika seja predominantemente veiculado pelo Aedes aegypti, as vias vertical e sexual de transmissão apresentam expressiva importância para a saúde reprodutiva. A transmissão sexual demanda o uso de intervenções profiláticas específicas, incluindo o uso do preservativo masculino ou feminino, principalmente entre casais que planejam gravidez. A transmissão vertical é ligada a graves anormalidades estruturais do sistema nervoso central e ainda não há vacina e nem recursos farmacológicos conhecidos que possam preveni-la. Como a doença é predominantemente assintomática, o não cumprimento dos princípios básicos de cuidados e orientações relacionadas à dispersão da infecção transcende a gravidade dos sintomas da doença.

This article addresses vector, sexual and vertical transmission of Zika virus, a topic covered in the Clinical Protocol and Therapeutic Guidelines for Comprehensive Care for People with Sexually Transmitted Infections, published by the Brazilian Ministry of Health in 2020. Although in Brazil Zika virus is transmitted most predominantly by Aedes aegypti, the vertical and sexual transmission routes are of significant importance for reproductive health. Sexual transmission demands the use of specific prophylactic interventions, including the use of male or female condoms, especially among couples planning pregnancy. Vertical transmission is linked to severe structural abnormalities of the central nervous system and there is still no vaccine or known pharmacological resources that can prevent it. As the disease is predominantly asymptomatic, failure to comply with basic principles of care and guidelines related to the spread of infection transcends the severity of the symptoms of the disease.

Este artículo aborda la transmisión vectorial, sexual y vertical del virus Zika, tema tratado en el Protocolo Clínico y Directrices Terapéuticas para la Atención Integral a Personas con Infecciones de Transmisión Sexual, publicado por el Ministerio de Salud de Brasil en 2020. Aunque en Brasil el virus Zika sea principalmente transmitido por Aedes aegypti, las vías vertical y sexual de transmisión son de gran importancia para la salud reproductiva. La transmisión sexual exige el uso de intervenciones profilácticas específicas, incluido el uso de preservativos masculinos o femeninos, especialmente entre las parejas que planean un embarazo. La transmisión vertical está ligada a graves anomalías estructurales del sistema nervioso central y todavía no existe una vacuna o recursos farmacológicos conocidos que puedan prevenirla. Como la enfermedad es predominantemente asintomática, el incumplimiento de los principios básicos de atención y las pautas relacionadas con la propagación de la infección trasciende la gravedad de los síntomas de la enfermedad.

Análise do conceito síndrome congênita pelo Zika vírus / Analysis of the concept of the Zika Virus congenital syndrome

Resumo O objetivo deste artigo é analisar o conceito de Síndrome Congênita pelo Zika Vírus. Trata-se de uma análise de conceito, baseado em Walker e Avant. Para operacionalização da busca foi realizada uma revisão sistemática. A essência do conceito Síndrome Congênita pelo Zika Vírus é determinada pelos atributos: calcificação intracraniana, ventriculomegalia e volume cerebral diminuído. Para que essa síndrome aconteça faz-se necessário que ocorram os antecedentes: transmissão via transplacentária de mãe infectada pela picada do mosquito Aedes SSP ou por via sexual. Com isso, resultam um conjunto de sinais e sintomas além da microcefalia fetal ou pós-natal, como por exemplo, atraso no desenvolvimento neuropsicomotor, anormalidades auditivas e visuais, desproporção craniofacial, suturas cranianas sobrepostas, osso occipital proeminente, excesso de pele nucal, epilepsia, irritabilidade, discinesia, hipertonia, hipotonia, hemiplegia, hemiparesia, espasticidade, hiperreflexia. O conceito de Síndrome Congênita pelo Zika Vírus é recém conhecido. O que determinará a presença do conjunto de sinais e sintomas pela infecção congênita do Zika vírus é a calcificação intracraniana e volume cerebral diminuído, podendo apresentar microcefalia já ao nascer ou apenas posteriormente.

Abstract The scope of this article is to analyze the concept of the Zika Virus Congenital Syndrome. It is a conceptual analysis, based on Walker and Avant. In order to operationalize the search, a systematic review was conducted. The essence of the concept of the Zika Virus Congenital Syndrome is determined by the following attributes: intracranial calcification, ventriculomegaly, and diminished brain volume. For this syndrome to occur, it is necessary to have the following antecedents: transplacental transmission of a mother infected by the bite of the Aedes SSP mosquito or by sexual contact. Accordingly, this entails a set of signs and symptoms that go beyond fetal or postnatal microcephaly, such as, for example, delayed neuropsychomotor development, auditory and visual abnormalities, craniofacial disproportion, overlapping cranial sutures, prominent occipital bone, excess nuchal skin, epilepsy, irritability, dyskinesia, hypertonia, hypotonia, hemiplegia, hemiparesis, spasticity and hyperreflexia. The concept of the Zika Virus Congenital Syndrome is newly acknowledged. The presence of the set of signs and symptoms by the Zika Virus Congenital Syndrome is determined by intracranial calcification and decreased brain volume, and the baby may present microcephaly at birth or subsequently.

Avaliação da armadilha ovitrampa iscada com atraente natural para o monitoramento de Aedes spp. em Dili, capital do Timor-Leste / Evaluation of the baited ovitrap with natural attractant for monitoring Aedes spp. in Dili, capital of East Timor

Resumo A dengue ocorre no Timor-Leste desde 2005, porém não existe um programa de monitoramento e controle do "Aedes aegypti". O objetivo deste estudo foi de avaliar a armadilha ovitrampa iscada com atraente natural como uma possível ferramenta para monitorar o vetor das arboviroses: Dengue (DENV), Chikungunya (CHIKV) e Zika (ZIKV). O estudo foi realizado na cidade de Dili, capital do Timor-Leste, entre as semanas epidemiológicas 32 (02/08) a 48 (02/12) de 2016. Foram instaladas 70 armadilhas Ovitrampa, em residências de 15 sucos (ruas), de quatro Postos Administrativos (bairros) da cidade. Para as analises dos dados utilizou-se os indicadores entomológicos: Índice de Positividade de Ovitrampa (IPO), Índice de Densidade Vetorial (IDV) e Índice de Densidade de Ovos (IDO). Durante o experimento foram coletados 158.904 ovos de Aedes spp.. O IPO demonstrou que todas as áreas tiveram 98% a 100% de armadilhas contendo ovos de Aedes spp.. Os indicadores IDO e IPO apresentaram correlações positivas e significativa com a temperatura. A defasagem de duas e três semanas para precipitação indicou correlação positiva significativa para IDV e IDO. Portanto, a armadilha ovitrampa é uma ferramenta que pode integrar as ações de um programa de monitoramento e controle de Aedes spp. no Timor-Leste.

Vector competence of Culex mosquitoes (Diptera: Culicidae) in Zika virus transmission: an integrative review / Competencia de los mosquitos Culex (Diptera: Culicidae) como vectores en la transmisión del virus del Zika: una revisión integradora / Competência vetorial de mosquitos Culex (Diptera: Culicidae) na transmissão do vírus Zika: revisão integrativa

ABSTRACT Objective. To identify studies on the competence of Culex mosquitoes as vectors for the transmission of Zika virus (ZIKV) around the globe. Methods. We performed an integrative review to identify relevant articles on specific experiments to determine whether Culex mosquitoes are vectors for ZIKV. The sources we used for our research were the Brazilian Periódicos CAPES electronic portal (MEDLINE/PubMed, ScienceDirect Journals, Nature Publishing Group, SciELO, Springer Link, and 250 other databases) and gray literature. Results. We identified 344 studies, of which 36 were considered for this review. In 8 studies, infection in salivary glands of Culex quinquefasciatus, Culex restuans, Culex tarsalis, and Culex coronator was detected. Cx. quinquefasciatus was the most studied among those confirmed as potential ZIKV vectors, and only strains of Asian lineages (THA/2014/SV0127-14; SZ01 (2016)) and American lineages (BRPE243 (2015); PRVABC59 (2015)) can infect the salivary glands of Culex mosquitoes. The tested African strains (MR766 and DAK AR 41525) were unable to infect salivary glands. Conclusions. There is still a lack of compelling evidence that indicates Culex spp. are a competent ZIKV vector, but they should remain a target for further monitoring studies, especially regarding ZIKV transmission to other species. Furthermore, studies should not be limited to studying whether their salivary glands are infected.(AU)

RESUMEN Objetivo. Identificar estudios sobre la competencia de los mosquitos Culex como vectores de la transmisión del virus del Zika en todo el mundo. Métodos. Se realizó una revisión integradora para identificar artículos relevantes sobre experimentos específicos dirigidos a determinar si los mosquitos Culex son vectores del virus del Zika. Se emplearon fuentes obtenidas a partir del portal electrónico de revistas CAPES (MEDLINE/PubMed, ScienceDirect Journals, Nature Publishing Group, SciELO, Springer Link, y otras 250 bases de datos) y la literatura gris. Resultados. Se identificaron 344 estudios, 36 de los cuales fueron considerados para esta revisión. En 8 estudios se detectó infección en las glándulas salivales de Culex quinquefasciatus, Culex restuans, Culex tarsalis y Culex coronator. Cx. quinquefasciatus fue la especie más estudiada entre las confirmadas como potenciales vectores del virus del Zika, y solo las cepas de linajes asiáticos (THA/2014/SV0127-14; SZ01 [2016]) y americanos (BRPE243 [2015]; PRVABC59 [2015]) pueden infectar las glándulas salivales de los mosquitos Culex. Las cepas africanas analizadas (MR766 y DAK AR 41525) no fueron capaces de infectar las glándulas salivales. Conclusiones. Aunque faltan pruebas convincentes que indiquen que las especies de Culex spp. son un vector competente del virus del Zika, estas deben seguir monitoreándose mediante estudios adicionales, especialmente respecto de su capacidad para transmitir el virus del Zika a otras especies. Esta vigilancia no debería limitarse solamente a determinar la infección en las glándulas salivales.(AU)

RESUMO Objetivo. Identificar estudos sobre a competência dos mosquitos Culex como vetores da transmissão do vírus Zika em todo o mundo. Métodos. Uma revisão integrativa foi realizada para identificar artigos relevantes sobre experimentos específicos para determinar se os mosquitos Culex são vetores do vírus Zika. As fontes utilizadas na pesquisa foram o portal eletrônico CAPES (MEDLINE/PubMed, ScienceDirect Journals, Nature Publishing Group, Sci-ELO, Springer Link, e outras 250 bases de dados) e a literatura cinza. Resultados. Foram identificados 344 artigos, dos quais 36 foram considerados para esta revisão. Oito artigos relataram infecção nas glândulas salivares de Culex quinquefasciatus, Culex restuans, Culex tarsalis e Culex coronator. Culex quinquefasciatus foi a espécie mais estudada entre as confirmadas como vetores potenciais do vírus Zika. Apenas as linhagens asiáticas (THA / 2014 / SV0127-14; SZ01 [2016]) e americanas (BRPE243 [2015]; PRVABC59 [2015]) podem infectar as glândulas salivares dos mosquitos Culex. As cepas africanas analisadas (MR766 e DAK AR 41525) não foram capazes de infectar as glândulas salivares. Conclusões. Ainda não há evidências convincentes para indicar que os mosquitos Culex são um vetor competente do vírus Zika. Contudo, estudos adicionais de monitoramento devem ser realizados, especialmente no que diz respeito à transmissão do vírus Zika para outras espécies de mosquitos. Além disso, os estudos não devem se limitar a estudar a infecção nas glândulas salivares.(AU)

Face social do controle do Aedes: em um bairro periférico de Fortaleza, Brasil, as mulheres tomam a palavra / The social face of Aedes control: women take the floor in a suburban district of Fortaleza, Brazil

Resumo O Aedes aegypti é um importante agente transmissor de afecções na atualidade, sendo o responsável por enfermidades como Zika, Chikungunya e os quatro sorotipos do Dengue. Por ocasião da relevância desse mosquito para o corpo social atual, investigações em Ecossaúde se tornam prementes, já que essa abordagem visa articular diferentes campos teóricos para entender as conexões históricas entre a natureza, a sociedade e a saúde. Partindo de uma premissa etnográfica, este estudo considerou as condições de desigualdade e injustiça que tornam vulneráveis a saúde de mulheres em torno do dengue, analisando práticas e percepções destas acerca dos potencias criadouros existentes no espaço público. Para compor o estudo, utilizou-se a entrevista semiestruturada e a observação participante, com uso de diário de campo. A pesquisa contou com a participação de dez mulheres moradoras de um bairro periférico da cidade de Fortaleza, Ceará, Brasil, tendo ocorrido no período de janeiro a agosto de 2014. Da Análise de Conteúdo emergiu a categoria "Iniquidade social, contexto e práticas no espaço público". A partir das narrativas, constatou-se que condições precárias de vida e evidente iniquidade social poderão influenciar em um contexto permeado por lixo, com grande potencial para a proliferação do mosquito causador da dengue.

Abstract Aedes aegypti is currently a critical disease agent and is responsible for viruses such as Zika, Chikungunya and Dengue's four serotypes. This mosquito's relevance to the current social body has come to the fore and triggered urgent EcoHealth investigations since this approach aims to articulate different theoretical fields to understand the historical linkages between nature, society and health. Based on an ethnographic premise, this study considered the unequal and unfair conditions that make women's health vulnerable to dengue, analyzing their practices and perceptions about the potential breeding grounds in the public space. A semi-structured interview and participant observation, as well as a field diary, were used to compose the study. The research included the participation of ten women living in the outskirts of Fortaleza, Ceará, Brazil, from January to August 2014. The category "Social inequality, context and practices in the public space" emerged from the content analysis. The narratives revealed that unstable living conditions and evident social inequality might influence in a context permeated by waste, with great potential for dengue's mosquito proliferation.

Expansão da circulação do vírus Zika da África à América, 1947-2018: revisão da literatura / Expansión de la circulación del virus Zika de África a América, 1947-2018: una revisión de literatura / Expansion of Zika virus circulation from Africa to the Americas, 1947-2018: a literature review

Objetivo: descrever as expansões temporal e geográfica da circulação do vírus Zika (ZIKV) em países e territórios, desde seu isolamento até 2018. Métodos: revisão não sistemática da literatura do período entre 1947 e 2018, utilizando a base MEDLINE e estimativas da Organização Mundial da Saúde. Resultados: desde seu isolamento em 1947, a circulação do ZIKV expandiu-se pela África, Ásia e Pacífico, até chegar à América em 2013, causando manifestações clínicas graves; as maiores soroprevalências foram registradas na ilha de Yap (74%) e no Brasil (63%); mutações genéticas, a ausência de imunidade e a alta susceptibilidade dos vetores podem ter influenciado sua transmissibilidade e ajudam a explicar a magnitude de sua expansão. Conclusão: a expansão da circulação do ZIKV nas Américas foi a mais ampla já registrada, possivelmente resultado de características populacionais e geográficas dos locais por onde o vírus circulou.

Objetivo: Describir las expansiones temporal y geográfica de la circulación del virus Zika en países y territorios, desde su aislamiento hasta 2018. Métodos: Revisión no sistemática de la literatura del período comprendido entre 1947 y 2018 utilizando la base MEDLINE y estimaciones de la Organización Mundial de la Salud. Resultados: Desde su aislamiento en 1947 la circulación del virus Zika se expandió por África, Asia y el Pacífico hasta llegar a América en 2013, causando manifestaciones clínicas graves. Las mayores seroprevalencias se registraron en la isla Yap (74%) y en Brasil (63%). Mutaciones genéticas, ausencia de inmunidad y alta susceptibilidad de los vectores pueden haber influenciado su transmisibilidad y ayudan a explicar la magnitud de su expansión. Conclusión: La expansión de la circulación del virus Zika en las Américas fue la más amplia ya registrada, posiblemente como resultado de características poblacionales y geográficas de los lugares por donde el virus circuló.

Objective: to describe the temporal and geographical expansion of Zika virus (ZIKV) circulation in countries and territories, from the time it was first isolated until 2018. Methods: This was a non-systematic literature review covering the period from 1947 to 2018 using the MEDLINE database and World Health Organization estimates. Results: Since its isolation in 1947, ZIKV circulation spread through Africa, Asia and the Pacific before reaching the Americas in 2013, causing serious clinical manifestations; the highest seroprevalence rates were recorded in Yap (74%) and in Brazil (63%); genetic mutations, absence of immunity and high vector susceptibility may have influenced ZIKV transmissibility and help to explain the magnitude of its expansion. Conclusion: The spread of ZIKV circulation in the Americas was the most extensive recorded thus far, possibly as a result of population and geographical characteristics of the sites where the virus circulated.

Identification of Zika virus in immature phases of Aedes aegypti and Aedes albopictus: a surveillance strategy for outbreak anticipation

A progressive increase in the circulation of arboviruses in tropical countries has been observed, accounting for 700,000 yearly deaths in the world. The main objective of this article was to identify the presence of Zika (ZIKV), dengue (DENV), and Chikungunya (CHIKV) viruses in immature stages of Aedes aegypti and Ae. albopictus. Household collections of immature phases of the vectors were carried out in the years 2015 and 2016. A total of 2902 dwellings were visited and the rate of infestation with larvae and pupae of Aedes mosquitoes was 283/1462 (19.4%) in March 2015 and 55/1440 (3.8%) in June 2015. In March 2015, 907 larvae/pupae were collected (583 or 64.3% of Ae. aegypti and 324 or 35.7% of Ae. albopictus) while in June 2015 there was a reduction in the number of immature forms found: 197 larvae/pupae (121 or 61.4% of Ae. aegypti and 76 or 38.6% of Ae. albopictus). This reduction was accompanied by a decrease in suspected human ZIKV cases from March to June 2015. The RT-qPCR performed in 18 pools identified that three (two of Ae. aegypti and one of Ae. albopictus) were positive for ZIKV, and none were positive for DENV or CHIKV. Our findings demonstrated that ZIKV was present in immature stages of insect vectors in the study region at least five months prior to the peak of ZIKV associated cases. Xenomonitoring of immature phases of the vectors may prove useful for predicting outbreaks.

Spatial distribution of Aedes aegypti (Diptera: Culicidae) in vulnerable areas for the transmission of arboviruses

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.

Zika Vírus na gestação / Zika Virus in pregnancy

A infecção congênita pelo zika vírus (ZIKV) tornou-se uma pandemia em meados de 2015 e é considerada uma emergência em saúde pública de interesse mundial, no que tange à prevalência, transmissão e possíveis sequelas neurológicas fetais. O artigo busca realizar uma revisão sobre a infecção do ZIKV na gestação e suas consequências para o feto. Realizada revisão a partir de estudos qualitativo, retrospectivo e documental, baseando-se em levantamento de produções científicas publicadas entre 2016 e 2018. Por meio da estratégia de busca, localizou-se 194 artigos, dos quais 28 foram selecionados para redação final. Conclui-se que as alterações ultrassonográficas, advindas de infecção no primeiro e segundo trimestre, são devidas à ação viral direta, efeito de imunoglobulinas e alterações na placentação. As alterações fetais são sobretudo as neurológicas, cardíacas e oftalmológicas. Gestantes com infecção comprovada, ou suspeitada, devem ser acompanhadas até o parto. Os investimentos em medicamentos e vacinas devem ser continuados.(AU)

Congenital zika virus (ZIKV) infection has become pandemic by mid-2015 and is considered a public health emergency of global concern with regard to prevalence, transmission and possible fetal neurological sequelae. The article aims to review the ZIKV infection in pregnancy and its consequences for the fetus. A review was carried out based on a qualitative, retrospective and documental studies, based on a survey of scientific productions published between 2016 and 2018. Through the search strategy, 194 articles were found, of which 28 were selected for final writing. It is concluded that ultrasonographic changes, due to infection in the first and second trimester, are due to direct viral action, immunoglobulins effect and changes in placentation. Fetal alterations are especially those neurological, cardiac and ophthalmologic. Pregnant women with proven or suspected infection should be followed up until delivery. Investments in drugs and vaccines should be continued.(AU)

Zika: an ongoing threat to women and infants / Zika: uma ameaça permanente para mulheres e crianças / Zika: una amenaza permanente para mujeres y niños

Recent data from the municipality of Rio de Janeiro, Brazil, shows a sharp drop in the number of reported occurrences of Zika during the summer of 2016/2017, compared to the previous summer. There is still a much higher incidence among women than men, almost certainly due to sexual transmission. An unexpected feature of the new data is that there are proportionally far more cases affecting children under 15 months than older age classes. By comparing incidence rates in 2016/2017 and 2015/2016, we were able to deduce the proportion of reported cases affecting men and women, and verify that gender disparity is still present. Women and children are still risk groups for Zika infection, even during non-epidemic seasons.

Dados recentes do Município de Rio de Janeiro, Brasil, mostram uma queda importante na notificação de casos de Zika no verão de 2016/2017, comparado ao verão anterior. A incidência ainda é muito mais alta em mulheres do que em homens, quase certamente em função da transmissão sexual. Uma característica inesperada dos novos dados é que, proporcionalmente, há muito mais casos em crianças abaixo dos 15 meses de idade, quando comparadas àquelas das faixas mais velhas. Ao comparar as taxas de incidência em 2016/2017 e 2015/2016, conseguimos deduzir a proporção de casos notificados em homens e mulheres e confirmar que a disparidade de gênero ainda existe. As mulheres e crianças ainda são grupos de risco para a infecção pelo vírus Zika, mesmo durante períodos não epidêmicos.

Datos recientes del municipio de Río de Janeiro, Brasil, muestran un descenso importante en la notificación de casos de Zika durante el verano de 2016/2017, comparado con el verano anterior. La incidencia todavía es mucho más alta en mujeres que en hombres, casi con seguridad debido a la transmisión sexual. Una característica inesperada de los nuevos datos es que, proporcionalmente, hay muchos más casos en niños por debajo de los 15 meses de edad, cuando se comparan con aquellas franjas con edad superior. Al comparar las tasas de incidencia en 2016/2017 y 2015/2016, conseguimos deducir la proporción de casos notificados en hombres y mujeres y confirmar que la disparidad de género todavía existe. Las mujeres y niños todavía son grupos de riesgo para la infección por el virus Zika, incluso durante períodos no epidémicos.

Zika infection decreases Aedes aegypti locomotor activity but does not influence egg production or viability

BACKGROUND Zika has emerged as a new public health threat after the explosive epidemic in Brazil in 2015. It is an arbovirus transmitted mainly by Aedes aegypti mosquitoes. The knowledge of physiological, behavioural and biological features in virus-infected vectors may help the understanding of arbovirus transmission dynamics and elucidate their influence in vector capacity. OBJECTIVES We aimed to investigate the effects of Zika virus (ZIKV) infection in the behaviour of Ae. aegypti females by analysing the locomotor activity, egg production and viability. METHODOLOGY Ae. aegypti females were orally infected with ZIKV through an artificial feeder to access egg production, egg viability and locomotor activity. For egg production and viability assays, females were kept in cages containing an artificial site for oviposition and eggs were counted. Locomotor activity assays were performed in activity monitors and an average of 5th, 6th and 7th days after infective feeding was calculated. FINDINGS No significant difference in the number of eggs laid per females neither in their viability were found between ZIKV infected and non-infected females, regardless the tested pair of mosquito population and virus strain and the gonotrophic cycles. Locomotor activity assays were performed regardless of the locomotor activity in ZIKV infected females was observed, in both LD and DD conditions. MAIN CONCLUSIONS The lower locomotor activity may reduce the mobility of the mosquitoes and may explain case clustering within households reported during Zika outbreaks such as in Rio de Janeiro 2015. Nevertheless, the mosquitoes infected with ZIKV are still able to disseminate and to transmit the disease, especially in places where there are many oviposition sites.

Follow up of a robust meta-signature to identify Zika virus infection in Aedes aegypti: another brick in the wall

The mosquito Aedes aegypti is the main vector of several arthropod-borne diseases that have global impacts. In a previous meta-analysis, our group identified a vector gene set containing 110 genes strongly associated with infections of dengue, West Nile and yellow fever viruses. Of these 110 genes, four genes allowed a highly accurate classification of infected status. More recently, a new study of Ae. aegypti infected with Zika virus (ZIKV) was published, providing new data to investigate whether this "infection" gene set is also altered during a ZIKV infection. Our hypothesis is that the infection-associated signature may also serve as a proxy to classify the ZIKV infection in the vector. Raw data associated with the NCBI/BioProject were downloaded and re-analysed. A total of 18 paired-end replicates corresponding to three ZIKV-infected samples and three controls were included in this study. The nMDS technique with a logistic regression was used to obtain the probabilities of belonging to a given class. Thus, to compare both gene sets, we used the area under the curve and performed a comparison using the bootstrap method. Our meta-signature was able to separate the infected mosquitoes from the controls with good predictive power to classify the Zika-infected mosquitoes.

Zika: probabilidad de establecimiento de su vector, Aedes aegypti, en Chile / Zika: probability of establishment of its vector, Aedes aegypti, in Chile

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.

Epidemiología de las principales enfermedades transmitidas por vectores en Colombia, 1990-2016 / Transmission scenarios of major vector-borne diseases in Colombia, 1990-2016

Resumen Introducción. Las enfermedades transmitidas por vectores representan más de 17 % de todas las enfermedades infecciosas y causan anualmente un millón de defunciones a nivel mundial. En Colombia, la malaria, el dengue, la enfermedad de Chagas y las leishmaniasis son condiciones endemoepidémicas persistentes. Objetivo. Determinar el comportamiento epidemiológico de las enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016. Materiales y métodos. Se hizo un estudio descriptivo del comportamiento epidemiológico de las principales enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016, con la información proveniente de fuentes oficiales secundarias. Resultados. En el periodo estudiado se registraron 5'360.134 casos de enfermedades transmitidas por vectores, de los cuales 54,7 % fueron de malaria y 24,9 % de dengue. Estos casos concentraron el 80 % de la carga acumulada de casos de enfermedades transmitidas por vectores. Las medianas de las tasas de incidencia fueron 1.371 y 188 por 100.00 habitantes para malaria y dengue, respectivamente. Además, los casos de chikungunya fueron 774.831 desde su introducción en el 2014 y, los de Zika, 117.674 desde su aparición en 2015. En las zonas rurales predominaron las enfermedades parasitarias transmitidas por vectores como la malaria, las leishmaniasis y la enfermedad de Chagas. A nivel urbano, predominaron el dengue, el chikungunya y el Zika. Conclusiones. La transmisión en Colombia de estas enfermedades es persistente en las zonas urbanas y en las rurales, y de tipo endemoepidémico en los casos de malaria, dengue, leishmaniasis y enfermedad de Chagas. Dicha transmisión se ha dado de manera focalizada y con patrones variables de intensidad. Asimismo, se mantienen las condiciones que han favorecido la transmisión emergente de nuevas arbovirosis.

Abstract Introduction: Vector-borne diseases account for more than 17% of all infectious diseases and annually they cause one million deaths worldwide. In Colombia, malaria, dengue, Chagas disease, and leishmaniasis are persistent endemo-epidemic events. Objective: To determine the behavior and transmission scenarios of vector-borne diseases in Colombia between 1990 and 2016. Materials and methods: We conducted a descriptive study on the epidemiological behavior of the main vector-borne diseases in Colombia between 1990 and 2016 based on information from official secondary sources. Results: During the study period, there were 5,360,144 cases of vector-borne diseases, 54.7% of which were due to malaria and 24.9% to dengue, accounting for 80% of the cumulative disease burden of vector-borne disease cases. The median incidence rates were 1,371 and 188 per 100,000 inhabitants for malaria and dengue, respectively. In addition, emerging events such as Chikungunya registered 774,831 cases since its introduction in 2014, while 117,674 Zika fever cases were reported since its emergence in 2015. In rural settings, parasitic vector-borne diseases such as malaria, leishmaniasis and Chagas disease predominated, while in urban scenarios dengue, chikungunya and Zika were predominant. Conclusions: Persistent epidemic and endemic transmission of vector-borne diseases in urban and rural settings in Colombia was observed mainly in the case of malaria, dengue, leishmaniasis and Chagas disease. Such transmission was focused and had variable intensity patterns. On the other hand, the conditions that have favored the emergence of new arboviruses persist.

Culex quinquefasciatus from areas with the highest incidence of microcephaly associated with Zika virus infections in the Northeast Region of Brazil are refractory to the virus

Zika virus (ZIKV) is widely distributed in Brazil and the Northeast Region (NE) is the most affected zone, showing the highest incidence of microcephaly associated with ZIKV congenital infections worldwide. We report attempts to infect three populations of Culex quinquefasciatus from severely affected sites in the NE and Southeast Region (SE) of Brazil with three strains of ZIKV isolated from these localities. An Aedes aegypti population from the SE was used as a positive control. All tested Cx. quinquefasciatus populations were refractory to the ZIKV isolates. For these reasons, we believe Cx. quinquefasciatus should not be considered a potential vector of ZIKV in Brazil.

Viruses vector control proposal: genus Aedes emphasis

Abstract The dengue fever is a major public health problem in the world. In Brazil, in 2015, there were 1,534,932 cases, being 20,320 cases of severe form, and 811 deaths related to this disease. The distribution of Aedes aegypti, the vector, is extensive. Recently, Zika and Chikungunya viruses had arisen, sharing the same vector as dengue and became a huge public health issue. Without specific treatment, it is urgently required as an effective vector control. This article is focused on reviewing vector control strategies, their effectiveness, viability and economical impact. Among all, the Sterile Insect Technique is highlighted as the best option to be adopted in Brazil, once it is largely effectively used in the USA and Mexico for plagues related to agribusiness.

Zika Virus Infection in Pregnant Women and Microcephaly / Infecção do vírus Zika em gestantes e microcefalia

Abstract From the discovery of the Zika virus (ZIKV) in 1947 in Uganda (Africa), until its arrival in South America, it was not known that it would affect human reproductive life so severely. Today, damagetothe central nervous system is known to be multiple, and microcephaly is considered the tip of the iceberg. Microcephaly actually represents the epilogue of this infection's devastating process on the central nervous system of embryos and fetuses. As a result of central nervous system aggression by the ZIKV, this infection brings the possibility of arthrogryposis, dysphagia, deafness and visual impairment. All of these changes of varying severity directly or indirectly compromise the future life of these children, and are already considered a congenital syndrome linked to the ZIKV. Diagnosis is one of the main difficulties in the approach of this infection. Considering the clinical part, it has manifestations common to infections by the dengue virus and the chikungunya fever, varying only in subjective intensities. The most frequent clinical variables are rash, febrile state, non-purulent conjunctivitis and arthralgia, among others. In terms of laboratory resources, there are also limitations to the subsidiary diagnosis. Molecular biology tests are based on polymerase chain reaction (PCR)with reverse transcriptase (RT) action, since the ZIKV is a ribonucleic acid (RNA) virus. The RT-PCR shows serum or plasma positivity for a short period of time, no more than five days after the onset of the signs and symptoms. The ZIKVurine test is positive for a longer period, up to 14 days. There are still no reliable techniques for the serological diagnosis of this infection. If there are no complications (meningoencephalitis or Guillain-Barré syndrome), further examination is unnecessary to assess systemic impairment. However, evidence is needed to rule out other infections that also cause rashes, such as dengue, chikungunya, syphilis, toxoplasmosis, cytomegalovirus, rubella, and herpes. There is no specific antiviral therapy against ZIKV, and the therapeutic approach to infected pregnant women is limited to the use of antipyretics and analgesics. Anti-inflammatory drugs should be avoided until the diagnosis of dengue is discarded. There is no need to modify the schedule of prenatal visits for pregnant women infected by ZIKV, but it is necessary to guarantee three ultrasound examinations during pregnancy for low-risk pregnancies, and monthly for pregnant women with confirmed ZIKV infection. Vaginal delivery and natural breastfeeding are advised.

Resumo Desde a descoberta do vírus Zika (VZIK) em 1947 em Uganda, na África, até sua chegada na América do Sul, não se tinha notícia de que ele seria capaz de comprometer a vida reprodutiva emhumanos de forma tão severa.Hoje, sabe-se que os danos sobre o sistema nervoso central são múltiplos, e a microcefalia é considerada a ponta do iceberg, visto que na realidade ela representa o epílogo de um processo devastador desta infecção sobre o sistema nervoso central do embrião e do feto. Em decorrência da agressão do sistema nervoso central pelo VZIK, esta infecção pode provocar artrogripose, disfagia, surdez e comprometimento visual. Todas estas alterações, de gravidade variável, direta ou indiretamente comprometem a vida futura dessas crianças, já sendo considerada uma síndrome congênita ligada aoVZIK. Uma das principais dificuldades na abordagemdessa infecção é relativa ao diagnóstico. Considerando a parte clínica, observa-se que ela apresenta manifestações comuns às infecções pelos vírus da dengue e da febre chikungunya, variando apenasemsuas intensidades subjetivas. As variáveis clínicas mais frequentes são o exantema, febrícula, conjuntivite não purulenta e artralgia. No tocante aos recursos laboratoriais, também existem limitações ao diagnóstico subsidiário. As provas de biologia molecular se fundamentam na reação em cadeia da polimerase (RCP) com ação da transcriptase reversa (TT), visto que o VZIK é umvírus ácido ribonucleico (ARN). ATRRCP apresenta positividade sérica ou plasmática por um período curto de tempo, não ultrapassando cinco dias após início dos sinais e sintomas. Esta pesquisa do VZIK na urina fica positiva por período mais prolongado, chegando a 14 dias. Ainda não existem técnicas seguras para diagnóstico sorológico dessa infecção. Não havendo complicações (meningoencefalite ou síndrome de Guillain-Barré), dificilmente são necessários mais exames complementares para avaliar o comprometimento sistêmico.No entanto, são necessáriasprovaspara descartar as outras infecções que causam exantema, como dengue, chikungunya, sífilis, toxoplasmose, citomegalovírus, rubéola e herpes. Sabe-se que não existe terapia antiviral específica contra o VZIK, e a abordagem terapêutica de gestantes portadoras da infecção limita-se ao uso de antitérmicos e analgésicos. Orienta-se evitar anti-inflamatórios até que o diagnóstico de dengue seja descartado. Sobre a condução do pré-natal, não há necessidade de modificar o cronograma de consultas pré-natais para gestantes que foram infectadas pelo VZIK, mas é necessária a garantia de três exames ecográficos durante a gravidez para gestantes de baixo risco, emensais para a gestante cominfecção confirmada pelo VZIK. Avia de parto é vaginal, e está liberado o aleitamento natural.