Cutting Edge: Transcriptional Profiling Reveals Multifunctional and Cytotoxic Antiviral Responses of Zika Virus-Specific CD8+ T Cells.

Zika virus (ZIKV) constitutes an increasing public health problem. Previous studies have shown that CD8+ T cells play an important role in ZIKV-specific protective immunity. We have previously defined antigenic targets of the ZIKV-specific CD8+ T cell response in humans. In this study, we characterized the quality and phenotypes of these responses by a combined use of flow cytometry and transcriptomic methods, using PBMCs from donors deriving from different geographical locations collected in the convalescent phase of infection. We show that ZIKV-specific CD8+ T cells are characterized by a polyfunctional IFN-γ signature with upregulation of TNF-α, TNF receptors, and related activation markers, such as CD69, as well as a cytotoxic signature characterized by strong upregulation of GZMB and CRTAM. The signature is stable and not influenced by previous dengue virus exposure, geographical location, or time of sample collection postinfection. To our knowledge, this work elucidates the first in-depth characterization of human CD8+ T cells responding to ZIKV infection.

Evaluation of a rapid water-surface sweeping method to accurately estimate numbers of Aedes aegypti (Diptera: Culicidae) late larval stages in large water-storage containers: comparison with pupal estimates.

INTRODUCTION: Since the methodologies used to calculate Stegomyia indices have been shown to be inadequate for assessing the risk of dengue virus transmission and targeting Aedes aegypti control strategies, new surveillance methods are needed. OBJECTIVE: To evaluate the water-surface sweeping method in combination with calibration factors to estimate the total number of Ae. aegypti late larval stages (L3/L4) in large water-storage containers at different temperatures at which transmission of dengue virus occurs. MATERIALS AND METHODS: Calibration factors were derived based on the proportion of L3/L4 recovered from a predetermined number of larvae using a net of specific dimensions and water-storage containers of different capacities and water levels in semi-field conditions and at four different altitudes (14, 358, 998 and 1,630 meters above sea level). The calibration factors obtained at 14 masl were then fully validated in a field study site at this altitude. RESULTS: Four calibration factors were derived at 14 masl (28-30°C) that were used to estimate the total L3/L4 numbers in large water storage containers greater than 20 L (n=478) at 1/3, 2/3 and full water-levels. This methodology was accurate and robust within and between the 10 pairs of field workers who applied it. Different calibration factors were, however, derived to accurately estimate the total L3/L4 numbers at each of the study sites located at 358, 998 and 1,630 masl, where average temperatures were 19°C, 24°C, and 26°C respectively. CONCLUSIONS: The accurate estimates of L3/L4 numbers calculated using the water surface sweeping method can be useful for evaluating intervention strategies directed against the larval stages.

Evaluation of a rapid water-surface sweeping method to accurately estimate numbers of Aedes aegypti (Diptera: Culicidae) late larval stages in large water-storage containers: comparison with pupal estimates / Evaluación de un método de barrido rápido sobre la superficie para estimar el número total de estados larvarios tardíos de Aedes aegypti (Diptera: Culicidae) en depósitos de agua de grandes capacidades: comparación con estimativos de pupas

Introduction. Since the methodologies used to calculate Stegomyia indices have been shown to be inadequate for assessing the risk of dengue virus transmission and targeting Aedes aegypti control strategies, new surveillance methods are needed. Objective. To evaluate the water-surface sweeping method in combination with calibration factors to estimate the total number of Ae. aegypti late larval stages (L3/L4) in large water-storage containers at different temperatures at which transmission of dengue virus occurs. Materials and methods. Calibration factors were derived based on the proportion of L3/L4 recovered from a predetermined number of larvae using a net of specific dimensions and water-storage containers of different capacities and water levels in semi-field conditions and at four different altitudes (14, 358, 998 and 1,630 meters above sea level). The calibration factors obtained at 14 masl were then fully validated in a field study site at this altitude. Results. Four calibration factors were derived at 14 masl (28-30°C) that were used to estimate the total L3/L4 numbers in large water storage containers greater than 20 L (n=478) at 1/3, 2/3 and full water-levels. This methodology was accurate and robust within and between the 10 pairs of field workers who applied it. Different calibration factors were, however, derived to accurately estimate the total L3/L4 numbers at each of the study sites located at 358, 998 and 1,630 masl, where average temperatures were 19°C, 24°C, and 26°C respectively. Conclusions. The accurate estimates of L3/L4 numbers calculated using the water surface sweeping method can be useful for evaluating intervention strategies directed against the larval stages.

Introducción. Las metodologías usadas para calcular los índices de Stegomyia son inadecuadas para evaluar el riesgo de transmisión del virus del dengue y, tampoco, permiten enfocar estrategias de control de Aedes aegypti, por lo cual se requiere desarrollar nuevos métodos para la vigilancia. Objetivo. Evaluar el método de barrido del agua superficial combinado con factores de calibración para estimar el número total estadios larvarios tardíos (L3/L4) de Ae. aegypti en depósitos de grandes capacidades a diferentes temperaturas de transmisión del virus del dengue. Materiales y métodos. Los factores de calibración se derivaron de la proporción de L3/L4 recolectadas con una malla de dimensiones específicas y a partir de un número conocido de larvas, en depósitos de diferentes capacidades y niveles de agua, en condiciones de campo simuladas y a cuatro altitudes diferentes (14, 358, 998 y 1.630 metros sobre el nivel del mar). Los factores de calibración obtenidos a 14 msnm fueron plenamente validados en el campo a esa altitud. Resultados. Se derivaron cuatro factores de calibración a 14 msnm (28°C-30°C) los cuales se emplearon para estimar el número total de L3/L4 en depósitos con capacidades mayores a 20 L (n=478) y a niveles de agua de un tercio, dos tercios y lleno. Esta metodología fue precisa y sólida en los 10 pares de trabajadores que aplicaron el método y entre ellos. Sin embargo, diferentes factores de calibración fueron derivados para estimar con precisión los números totales de L3/L4 en cada uno de los sitios de estudio localizados a 358, 998 y 1.630 msnm, donde las temperaturas promedio fueron de 19°C, 24°C y 26°C, respectivamente. Conclusión. La estimación precisa del número total de L3/L4 usando el barrido descrito permite proponer el uso de este método para evaluar estrategias de control dirigido a contra estados larvarios.