Reemergencia de la encefalitis equina del oeste (WEEV) en la Argentina: una revisión de aspectos epidemiológicos, virológicos y clínicos de relevancia / Reemergence of western equine encephalitis in Argentina

La encefalitis equina del oeste (WEEV, por su sigla en inglés, Western Equine Encephalitis) es una enfermedad reemergente en Argentina a partir del año 2023. La co-municación inicial fue en 1933, las últimas epizootias ocurrieron en 1983 y el último caso humano se registró en 1996. Se revisan las características del agente causal, la ecología con especial referencia a los vectores iden-tificados en el país, su competencia en la transmisión y el ciclo así como los factores de riesgo para adquirir la enfermedad. La situación epidemiológica en equinos y humanos desde noviembre 2023 hasta marzo 2024 es analizada. Se describen las formas clínicas de presen-tación de la enfermedad humana, las posibilidades evo-lutivas, los datos disponibles en los casos confirmados y el tratamiento. La metodología y algoritmo empleados para el diagnóstico etiológico en el Centro Nacional de Referencia son detallados. Las estrategias para la pre-vención y el control se basan en la vacunación de los equinos, el saneamiento ambiental y el control del foco ante la presentación de la enfermedad animal (vigilancia epidemiológica activa)

Western equine encephalitis (WEE) is a re-emerging dis-ease in Argentina starting in 2023. Since the initial notifi-cation in 1933, the last epizootics occurred in 1983, and the last human case was recorded in 1996.The charac-teristics of the causative agent, the ecology with special reference to vectors identified in the country, their compe-tence in transmission, and the cycle as well as the risks factors for acquiring the disease, are reviewed.The epidemiological situation in horses and humans from November 2023 to March 2024 is analyzed. The clinical presentation of the human disease, its evolutionary po-tential, available data in confirmed cases, and the treat-ment are described.The methodology and algorithm used for the etiological diagnosis at the National Reference Center are detailed. Strategies for prevention and control are based on vaccination of horses, environmental sani-tation and outbreak control in the presence of the animal disease (active epidemiological surveillance)

Vacunas contra el virus chikungunya: avances y perspectivas

El virus chikungunya (CHIKV) es un alfavirus cuya infección provoca una enfermedad caracterizada principalmente por fiebre y dolores articulares/musculares. Entre 25-50% de las infecciones se presentan con enfermedad crónica que puede durar de meses a años. El primer brote de CHIKV en Paraguay corresponde al año 2015, siendo el último en el año 2022/2023. Diversos candidatos vacunales contra CHIKV se encuentran en diferentes etapas de desarrollo, e incluso recientemente (noviembre/2023) fue aprobada la primera vacuna contra CHIKV llamada VLA1553 (Ixchiq). Adicionalmente, al menos 30 candidatos vacunales se encuentran en ensayos preclínicos/clínicos. Con la aprobación de la primera vacuna contra CHIKV y la posibilidad de otras que lleguen al mercado prontamente, debido al estado avanzado de otros candidatos vacunales, se abrirá un nuevo escenario en esta enfermedad. Se espera que la introducción de vacunas efectivas genere un avance importante para la prevención de esta enfermedad, disminuyendo los casos agudos y los efectos crónicos de la infección por el virus. En este trabajo de revisión se analiza el avance de las vacunas contra CHIKV, además de examinar los desafíos de vigilancia epidemiológica que plantean la introducción de estas vacunas.

Chikungunya virus (CHIKV) is an alphavirus that causes an illness characterized mainly by fever and joint/muscle pain. Between 25-50% of infections present with chronic diseases that can last from months to years. The first outbreak of CHIKV in Paraguay occurred in 2015, with the last outbreak occurring in 2022/2023. Several vaccine candidates against CHIKV are in different stages of development, and even recently (November/2023), the first vaccine against CHIKV, called VLA1553 (Ixchiq), was approved. In addition, at least 30 vaccine candidates are available for preclinical and clinical trials. With the approval of the first vaccine against CHIKV and the possibility of others coming to the market soon, due to the advanced status of other vaccine candidates, a new scenario will open for this disease. The introduction of effective vaccines is expected to generate an important advance in the prevention of this disease, reducing acute cases and the chronic effects of viral infection. This review analyzes the progress of CHIKV vaccines and examines the epidemiological surveillance challenges posed by the introduction of these vaccines.

Chikungunya virus infection in the southernmost state of Brazil was characterised by self-limited transmission (2017-2019) and a larger 2021 outbreak

BACKGROUND Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.

Étiologies des méningites et méningoencéphalites dans les services de réanimation polyvalente à Libreville de 2020 à 2021 / Etiologies of meningitis and meningoencephalitis in intensive care units of Libreville from 2020 to 2021

Introduction. Les méningites/méningo-encéphalites sont des urgences médicales d'étiologies variées. La technique de diagnostic Multiplex Polymerase Chain Reaction (PCR) permet de détecter la présence de bactéries et de virus dans le liquide céphalorachidien (LCR) avec une spécificité et une sensibilité ≥ 90%. L'objectif de cette étude était d'identifier en utilisant cette technique, les principaux germes responsables des méningites et méningo-encéphalites en réanimation à Libreville. Patients et méthodes. Nous avons mené une étude transversale allant d'octobre 2020 à septembre 2021. Les critères d'inclusion étaient : être admis en réanimation au CHUL et à l'HIAOBO pour suspicion de méningite ou méningo-encéphalite, obtenir l'accord des familles pour l'analyse du liquide céphalorachidien (LCR) par multiplex PCR. Les variables étudiées étaient : la fréquence, les données sociodémographiques, les aspects cliniques et paracliniques. Résultats. Soixante et onze patients ont répondu aux critères d'inclusion. L'âge moyen était de 21,1 ± 10,4 ans et le sex ratio de 1,2. Les motifs d'admission étaient l'altération de l'état de conscience (77%) et l'état de mal épileptique (21%). Plasmodium falciparum a été retrouvé seul chez 38 patients (53,5%) et associé à Listeria monocytogenes chez 4 patients (1,4%). Les méningo-encéphalites à Herpès simplex virus ont été observées chez 4 patients (1,4%) dont l'âge variait entre 40 ans et moins de 50 ans. Un patient (1,4%) présentait une coinfection à S. épidermidis, flavivirus et alphavirus. Des méningo-encéphalites sans germes ont été observées chez 5 patients (%). Conclusion. Le principal germe responsable de méningoencéphalite en réanimation à Libreville est P. falciparum. Des virus tels que le flavivirus et l'alphavirus non détectés par les méthodes usuelles ont aussi été mis en évidence grâce au multiplex PCR.

Introduction. Meningitis/meningoencephalitis are medical emergencies of various etiologies. The Multiplex Polymerase Chain Reaction (PCR) technique allows the detection of the presence of bacteria and viruses in the cerebrospinal fluid (CSF) with a specificity and sensibility of above 90%. The aim of this study was to identify the most common germs responsible for meningitis and meningoencephalitis in the intensive care units of Libreville using this technique,. Patients and methods. We conducted a transversal study from October 2020 to September 2021. Inclusion criteria were: being admitted to intensive care unit of CHUL and HIAOBO for suspicion of meningitis or meningoencephalitis and having the parent's approval for multiplex PCR analysis of CSF. Variables studied included frequency, sociodemographic data, clinical and paraclinical aspects. Results. Seventy one patients were included. Mean age was 21.1 ± 10.4 years and the sex ratio was 1.2. Reasons for admission were altered consciousness (77%) and epilepsy (21%). Plasmodium (P) faciparum was detected alone in 38 cases (53.5%) and associated to Listeria monocytogenes in 4 patients (5.6%). Herpex simplex viral meningoencephalitis was observed in 4 patients (5.6%) aged between 40 and less than 50 years. One patient (1.4%) had co-infection with S. epidermidis, flavivirus and alphavirus. Meningoencephalitis with no germs was found in 5 patients (7%). Conclusion. The main etiology of meningoencephalitis in intensive care units of Libreville is P. falciparum. Viruses not detected by usual methods like flavivirus and alphavirus were detected by multiplex PCR.

Chikungunya associated vulvitis: case report and literature review / Vulvite associada a Chikungunya: relato de caso e revisão de literatura

Introduction: Chikungunya virus is spreading worldwide due to migration and globalization and could be presented with systemic and with unusual symptoms. Objective: To report a case of virus-transmitted infection detected in a woman during the gynecological examination at a vulvar clinic. Case report: A 73-year-old Caucasian woman attended a vulvar clinic because of dyspareunia and vulvar burning. Ulcers were observed on labia minora and perineum. A Chikungunya was diagnosed by seroconversion in paired specimens. She was prescribed prednisolone 40 mg once a day for 10 days. After oral steroid treatment, the woman had no body rashes or lesions on her genitals. Conclusion: This study emphasized that rare signs of unusual vulvitis with ulcers could be associated with Chikungunya infection.

Introdução: O vírus Chikungunya está se espalhando pelo mundo por conta da migração e da globalização, podendo apresentar sintomas sistêmicos e incomuns. Objetivo: Relatar um caso de infecção pelo vírus detectado em uma mulher por ocasião do exame ginecológico em clínica de patologia vulvar. Relato do caso: Uma mulher caucasiana de 73 anos foi a uma clínica vulvar por causa de dispareunia e queimação vulvar. Úlceras foram observadas nos pequenos lábios e no períneo. O diagnóstico de Chikungunya foi realizado por soroconversão em espécimes pareados. Foi prescrita prednisolona 40 mg uma vez ao dia por dez dias. Após o tratamento com esteróides orais, a mulher não apresentou erupções ou lesões nos órgãos genitais. Conclusão: Este estudo enfatizou que quadros raros de vulvite com úlcera podem estar associados à infecção por Chikungunya.

Virus Mayaro, un alphavirus olvidado en Colombia: posible efecto sobre la salud pública / Mayaro virus, an alphavirus forgotten in Colombia: possible effect on public health

Sobre el Mayaro virus poco se conoce sobre su transmisión y patogénesis. Se sabe que habita en diferentes zonas del hemisferio occidental y que es transmitido por los Aedes aegypti y albopictus (Diptera: Culicidae). Ya se han investigado escenarios donde su circulación puede superponerse y generar infecciones mixtas, y por ello ha ganado importancia en la salud pública, puesto que puede ocasionar alto riesgo de brotes con manifestaciones clínicas graves similares a la de los virus Zika, Chikungunya y el Dengue países como Trinidad, Brasil, México, Venezuela, Honduras, Salvador, Costa Rica, Panamá, Perú, Argentina, Surinam, Guyana, Venezuela, Ecuador y Bolivia. Colombia está expectante de una aparición concomitante junto con ZIKV y CHIKV. Se realizó una búsqueda exhaustiva en PubMed, Science Direct, Clinical Key y Ebsco sobre el Mayaro virus, epidemiología, su estructura molecular, ciclo de transmisión, sintomatología clínica, métodos diagnósticos, factores de riesgo, control y prevención, así como tratamiento actual, para conocer un panorama más amplio sobre su problemática..(Au)

About Mayaro virus, there is currently little knowledge of its transmission and pathogenesis. It is known to inhabit different areas of the Western Hemisphere and is transmitted by the Aedes aegypti and albopictus (Diptera: Culicidae). Numerous authors have focused their research given coexistence in scenarios where the circulations of all these viruses can somehow overlap and generate mixed infections. This agent has been gaining prominence at the public health level, due to the possibility of causing high risk of outbreaks with serious clinical manifestations similar to that of Zika viruses, Chikungunya virus and Dengue, in several countries, such as Trinidad, Brazil, Mexico, Venezuela, Honduras, Salvador, Costa Rica, Panama, Peru, Argentina, Suriname, Guyana, Venezuela, Ecuador and Bolivia. Colombia is looking forward to a concomitant onset in the near future along with ZIKV and CHIKV. Taking into account the above, a thorough search was carried out of the existing literature, on Mayaro virus, its molecular structure, transmission cycle, clinical symptomatology, diagnostic methods, risk factors, control and prevention, as well as treatment, to learn a broader picture of the problem that lurks. All this, through search engines like PubMed, Science Direct, Clinical Key and Ebsco..(Au)

Momento de considerar otras arbovirosis luego del virus mayaro / Time to Consider Other Arbovirus Diseases after mayaro Virus

Introducción: En los últimos años, debido a los movimientos migratorios, se ha desarrollado una expansión de nuevas enfermedades, como chikungunya, zika, oropuche y mayaro. Caso clínico: Paciente que manifestaba síntomas de fiebre, cefalea y artralgias persistente. Después de un arduo estudio y eliminación de otras patologías se llega al diagnóstico de virus mayaro. El paciente residía en una zona nororiental del Perú. Se brindó tratamiento de soporte junto con hidratación, paracetamol 500 mg cada 8 horas y se indicó cita diaria para evaluación. El paciente evolucionó favorablemente a los pocos días. Conclusiones: La vigilancia, las pruebas y el control vectorial siguen siendo claves para prevenir la propagación de este tipo de virus. La posibilidad de que el virus mayaro se urbanice aún más. Se debe tener siempre en cuenta el diagnóstico diferencial de virus mayaro(AU)

Introduction: In recent years, due to migratory movements, an expansion of new diseases has developed, such as chikungunya, zika, oropuche and mayaro. Clinical case: Patient with the following symptoms: fever, headache and persistent arthralgia. After an arduous study and ruling out other possible diseases, we diagnose mayaro virus. The patient resided in a northeastern part of Peru. Supportive treatment was provided along with hydration; paracetamol 500 mg every 8 hours and daily appointment for evaluation was indicated. The patient evolved favorably within a few days. Conclusions: Surveillance, testing and vector control are still key to monitoring and preventing the spread of this type of virus. The possibility of mayaro virus becoming more urbanized is worthy of attention. The differential diagnosis of mayaro virus should always be considered(AU)

Comparative assessment of the replication efficiency of dengue, yellow fever, and chikungunya arboviruses in some insect and mammalian cell lines

Abstract INTRODUCTION: Insect cell cultures play an essential role in understanding arboviral replication. However, the replicative efficiency of some of these viruses such as dengue (DENV), yellow fever (YFV), and chikungunya (CHIKV) in a new cellular substrate (Lulo) and in the other two recognized cell lines has not been comparatively assessed. METHODS: Vero, C6/36, and Lulo cell lines were infected with DENV, YFV, and CHIKV. The viral progeny was quantified through plaque assays and quantitative reverse transcription-polymerase chain reaction, while for DENV2, the findings were confirmed by immunofluorescence antibody assay. RESULTS: The higher DENV2 titer (from multiplicity of infection 0.001) was obtained on day four post-infection in C6/36 and on day six in Vero cells, while the Lulo cell line was almost impossible to infect under the same conditions. However, C6/36 showed the highest values of viral RNA production compared to Vero cells, while the quantification of the viral RNA in Lulo cells showed high levels of viral genomes, which had no correlation to the infectious viral particles. CONCLUSIONS: C6/36 was the most efficient cell line in the alpha and flavivirus production, followed by Vero cells. Thus, Lulo cells may be a useful substrate to study the mechanisms by which cells evade viral replication.

A localized outbreak of Chikungunya virus in Salvador, Bahia, Brazil

A localized Chikungunya virus (CHIKV; East/Central/South African genotype) outbreak (50 cases, 70% laboratory-confirmed; attack rate: 5.3 confirmed cases/100 people) occurred in a Salvador, Brazil neighborhood, between Apr-Jun/2017. Highly clustered cases in space and time, mostly along a single street, highlight an increased risk of CHIKV transmission among pockets of susceptible populations. This finding underscores the need for ongoing local level surveillance for arboviral outbreaks.

Seroepidemiology of arbovirus in communities living under the influence of the lake of a hydroelectric dam in Brazil / Soroepidemiologia das arboviroses em comunidades que vivem sob a influência do lago de uma usina hidrelétrica no Brasil

Abstract Introduction The arbovirus proposes an important problem of public health in Brazil, especially in the Amazon, due to its capacity to cause outbreaks with high levels of morbidity-mortality in humans as well as in animals. Objective This paper had the objective to estimate the prevalence of antibodies to arbovirus in communities that live under the influence of the artificial lake of UHE Tucuruí in the State of Pará, Brazil. Method The analytical transversal study has selected 657 blood serum samples of individuals over 18, both genders, residents at the Sustainable Development Reserves (SDR) in the region of the lake of UHE Tucuruí. The epidemiological information has been registered in an instrument especially designed for such a study and the blood samples were collected in two periods of high and low tide of the lake. The blood serum tests were performed by the method of hemagglutination inhibition (HI). Results The results revealed a prevalence of positive antibodies to arbovirus of 85.0%, being 84.1% related to Flavivirus (vaccine strain of YFV), 25.5% related to Alphavirus and 34.6% to Bunyavirus. The results of serum prevalence to arbovirus between the periods of high tide and low tide have revealed significance amongst the Alphavirus, not observed in the other families. Conclusion In general, the data from this paper have suggested that the anthropoid actions on the environment of the lake have become determinant factors for the prevalence of arboviral antibodies.

Resumo Introdução Os arbovírus representam um importante problema de saúde pública no Brasil, especialmente na Amazônia, devido à sua capacidade de causar surtos em seres humanos e em animais. Objetivo Este trabalho teve o objetivo de estimar a prevalência de anticorpos para arbovírus em comunidades que vivem sob a influência do lago artificial de barragem hidrelétrica no Brasil. Método O estudo transversal analítico selecionou 657 amostras de sangue de indivíduos de ambos os sexos, residentes na região do lago. As informações epidemiológicas foram registradas em um instrumento concebido para este estudo e as amostras de sangue foram coletadas em períodos de maré alta e maré baixa do lago. Os testes sorológicos foram realizados pelo método de inibição da hemaglutinação (IH). Resultados Os resultados revelaram uma prevalência de anticorpos positivos para arbovírus de 85%, com 84,1% referentes ao Flavivirus (cepa vacinal de FA), 25,5% em relação ao Alphavirus e 34,6% para Orthobunyavirus. Os resultados de prevalência de anticorpos para arbovírus entre os períodos de maré alta e maré baixa revelaram significância entre os Alphavirus. Conclusão Em geral, os dados sugerem que as ações antrópicas no ambiente do lago tornaram-se fatores determinantes para a prevalência de anticorpos arbovirais.

Will Mayaro virus be responsible for the next outbreak of an arthropod-borne virus in Brazil?

Abstract Mayaro virus is an alphavirus from the Togaviridae family and is transmitted mainly by Hemagogus mosquitoes. This virus circulates in high-density tropical forests or rural areas of Central and South America causing a disease characterized by high-grade fever, maculopapular skin rash and marked arthralgia that, in some patients, can persist for long periods after infection and may be misinterpreted as chikungunya. Although only a few outbreaks involving this virus have been reported, in the last years the number of Mayaro virus infections has increased in the central and northern regions of Brazil. In this review, we describe the reported prevalence of this infection over the years and discuss the circumstances that can contribute to the establishment of an urban mayaro virus epidemic in Brazil and the problems encountered with the specific diagnosis, especially the antigenic cross-reactivity of this pathogen with other viruses of the same family.

Estandarización de una técnica de RT-PCR anidada para detección de alfavirus / Standardization of a nested RT-PCR technique for alphavirus detection

El género Alphavirus está constituido por virus de ARN de los cuales, varias especies son causantes de enfermedades humanas y animales como los virus chikungunya, Mayaro y los virus de encefalitis equinas, por lo que son considerados un problema de salud pública a nivel regional. En Paraguay han sido reportadas infecciones humanas por chikungunya pero son necesarios más estudios para ampliar conocimientos sobre circulación y ecoepidemiología de los alfavirus. La transcripción reversa de ARN seguida de una reacción en cadena de la polimerasa (RT-PCR) anidada es de gran utilidad como herramienta diagnóstica y en la vigilancia epidemiológica. El objetivo de este estudio fue definir las condiciones óptimas de reacción y determinar el límite de detección para una RT-PCR anidada para la detección genérica de alfavirus. El límite de detección obtenido, de 0,47 UFP/mL, indica una alta sensibilidad, pudiéndose aplicar la técnica a muestras humanas y animales de suero, líquido cefalorraquídeo, órganos y a pooles de mosquitos. Este trabajo servirá de base a otros estudios de detección e identificación de especies de alfavirus circulantes en nuestro país, lo que contribuiría a fortalecer su vigilancia y prevención.

The genus Alphavirus consists of RNA viruses of which several species areresponsible for human and animal diseases, such as chikungunya, Mayaro and equineencephalitis viruses, and are therefore considered a regional public health problem. InParaguay, human infections have been reported by chikungunya, but more studies areneeded to increase knowledge on the circulation and ecoepidemiology of alphaviruses.Reverse RNA transcription followed by a nested polymerase chain reaction (RT-PCR) isvery useful as a diagnostic tool and in epidemiological surveillance. The objective ofthis study was to define optimal reaction conditions and to determine the limit ofdetection for a nested RT-PCR for generic alphavirus detection. The detection limitobtained, of 0,47 PFU/mL, indicate high sensitivity, and the possibility of applying thetechnique to human and animals samples of serum, cerebrospinal fluid, organs andmosquito pools. This work will serve as a basis for other studies of detection andidentification of alphavirus species circulating in our country, which would helpstrengthen the surveillance and prevention.

Sensitivity and detection of chikungunya viral genetic material using several PCR-based approaches

Abstract INTRODUCTION: Chikungunya fever is a condition resulting from infection by chikungunya virus (CHIKV), an Aedes sp.-transmitted virus. This disease has been diagnosed in thousands of cases in the Americas, particularly in Brazil, in recent years, and there is an ongoing epidemic of chikungunya fever in Brazil that began in 2014. Clinical diagnosis is difficult; only a few cases have been confirmed by laboratory tests due to the low number of specific, efficient tests available for virus or antibody detection. Here, we aimed to evaluate different polymerase chain reaction (PCR) approaches for detection of CHIKV genetic material. METHODS: Specific primers and probes within the viral capsid gene region were designed for this work. To evaluate the analytic sensitivity of detection, human sera were spiked with serial dilutions of the viral stock. Several PCR protocols were performed to investigate the sensitivity of CHIKV RNA detection in serum dilutions ranging from 106 to 1 PFU equivalents. RESULTS: The technique showing the greatest sensitivity was a real-time PCR assay using specific probes that could detect the genetic material of the virus at all dilutions, followed by conventional PCR. Digital PCR showed low sensitivity and was much more expensive than other technologies. Digital PCR should be used for specific purposes other than clinical diagnosis. CONCLUSIONS: Although quantitative PCR using probes was more expensive than the use of intercalating dyes or conventional PCR, it had the highest sensitivity out of all tested PCR approaches.

Circulación de virus Chikungunya en el estado Aragua (Venezuela) durante el año 2014 / Circulation of Chikungunya virus in Aragua state (Venezuela) during the year 2014

El virus chikungunya (CHIKV) es un Alfavirus causante de la fiebre chikungunya (CHIKF). En Venezuela, una región desprovista de inmunidad contra CHIKV y con presencia de Aedes aegypti y Aedes albopictus, el primer caso importado fue reportado por las autoridades sanitarias en junio de 2014. Por la relevancia del hecho, se analizaron 94 muestras de pacientes febriles que acudieron a los centros de salud públicos y privados del estado Aragua entre enero y diciembre de 2014, mediante la detección de los fragmentos de los genes nsP4 (Alfavirus) y E1 (CHIKV) utilizando técnicas moleculares, como Transcripción Reversa acoplada a Reacción en Cadena de la Polimerasa (RT-PCR) y/o secuenciación nucleotídica. Los resultados indicaron positividad en 19,2 % de las muestras analizadas. Se vieron afectados pacientes con edades entre 6 y 66 años, con predominio del sexo femenino (12/18). Clínicamente, todos los pacientes positivos a CHIKV manifestaron signos y síntomas asociados a CHIKF, tales como fiebre (18/18), artralgia (18/18) y erupción (16/18), entre otros. A pesar de que la positividad puede considerarse baja con relación a lo reportado en otras comunidades, este estudio representa el primer reporte local de detección molecular de CHIKV en Venezuela (estado Aragua) durante el año 2014.

Chikungunya virus is an Alphavirus that causes chikungunya Fever (CHIKF). In Venezuela, a region devoid of immunity against CHIKV and presence of Aedes aegypti and Aedes albopictus. The first imported case was reported by health authorities in June 2014. The relevance of the fact, 94 samples of febrile patients who came to the centers of public and private health Aragua state between january and december for detection of the nsP4 (Alphavirus) and E1 (CHIKV) fragments were analyzed by molecular techniques (Reverse Transcriptase Polymerase Chain Reaction and/or nucleotide sequencing). The results showed 19.2 % of positivity by CHIKV. Clinically all CHIKV positive patients showed signs and symptoms related with CHIKF, such as fever (18/18), arthralgia (18/18) and rash (16/18), among others. Were affected patients between the ages of 6 and 66 years with a predominance of the female sex (12/18). Although the positivity may be considered low compared to those reported in other communities, this represents the first local report of molecular detection of CHIKV in Venezuela (Aragua state) during 2014.

Molecular detection of flaviviruses and alphaviruses in mosquitoes (Diptera: Culicidae) from coastal ecosystems in the Colombian Caribbean

Arboviruses belonging to the genera Flavivirus and Alphavirus were detected in mosquitoes in a rural area of San Bernardo del Viento (Córdoba, Colombia). A total of 22,180 mosquitoes were collected, sorted into 2,102 pools, and tested by generic/nested reverse transcription-polymerase chain reaction. Venezuelan equine encephalitis virus, dengue virus, West Nile virus, St. Louis encephalitis virus, yellow fever virus, and Culex flavivirus were detected and identified by sequencing. The detection of arboviral pathogens in this zone represents possible circulation and indicates a human health risk, demonstrating the importance of virological surveillance activities.

Clonación de secuencias de alfavirus y flavivirus para su uso como controles positivos en el diagnóstico molecular / Cloning alphavirus and flavivirus sequences for use as positive controls in molecular diagnostics

RESUMEN El objetivo de la investigación fue obtener controles positivos para la validación de técnicas moleculares (RT-PCR) utilizadas en diagnóstico e investigación de infecciones virales. A partir de cepas de CHIKV, Zika, DENV-1, DENV-2, DENV-3 y DENV-4, se extrajeron ARN virales para obtener por RT-PCR los ADN complementarios (ADNc) de las secuencias nsP4 (CHIKV), NS5 (virus Zika), C/prM-M y 5´UTR-C (DENV-1, DENV-2, DENV-3, DENV-4) que fueron clonados en pGEM®-T Easy. La clonación se confirmó mediante PCR de colonias, de las cuales se extrajo el ADN plasmídico para la verificación de la clonación de los fragmentos. Se logró la clonación de ADNc correspondientes a nsP4, NS5, C/prM-M y 5´UTR-C de los distintos agentes virales. En conclusión se obtuvieron los plásmidos recombinantes con cada una de las secuencias especificadas para su posterior valoración como controles positivos en técnicas moleculares, evitando el uso de cultivos celulares que pueden resultar costosos, laboriosos y potencialmente peligrosos.

ABSTRACT The purpose of the study was to obtain a positive control to validate molecular techniques (reverse transcription- polymerase chain reaction [RT-PCR]) used in the diagnosis and research of viral infections. From strains of Chikungunya virus (CHIKV), Zika virus, and Dengue virus (DENV-1, DENV-2, DENV- 3, and DENV-4) viral RNAs were extracted to obtain complementary DNA using RT-PCR from the nsP4 (CHIKV), NS5 (Zika virus), C/prM-M, and 5′UTR-C (DENV-1, DENV-2, DENV-3, DENV-4) sequences, which were cloned into pGEM®-T Easy. Cloning was confirmed through colony PCR, from which plasmid DNA was extracted for fragment cloning verification. Cloning of cDNA corresponding to nsP4, NS5, C/prM-M, and 5′UTR-C of the different viral agents was achieved. In conclusion, recombinant plasmids were obtained with each of the sequences specified for further assessment as positive controls in molecular techniques in an effort to avoid the use of cell cultures, which can be costly, time-consuming, and potentially dangerous.

Estandarización de técnicas para el diagnóstico molecular de flavivirus y alfavirus / Standarization of molecular techniques for diagnosis of flavivirus and alphavirus

Los flavivirus y alfavirus afectan la salud de los humanos. En Venezuela y de forma particular en Aragua, las comunidades se han visto afectadas por algunos de los miembros de estos géneros, como Dengue (DENV), y Chikungunya (CHIKV). DENV circula en Aragua desde 1989 causando brotes de importancia clínica, mientras que CHIKV hizo su aparición en 2014. En Aragua, el diagnóstico se había dirigido hacia la detección de DENV, sin embargo la situación con CHIKV generó la necesidad de ampliar el espectro diagnóstico hacia otros agentes virales. En el Laboratorio Regional de Diagnóstico e Investigación del Dengue y otras Enfermedades Virales se adaptaron dos protocolos de RT-PCR previamente descritos para detectar miembros de estos géneros haciendo uso de cepas controles para flavivirus (DENV y Zika) y alfavirus (CHIKV). Ambas técnicas sufrieron modificaciones en la concentración de algunos reactantes (MgCl2, dNTP´s, y cebadores) utilizados en la segunda reacción de PCR. El resto de las condiciones se mantuvieron iguales a las descritas originalmente. Las metodologías estandarizadas permitieron amplificar hasta 1 fg de ARN viral de los controles empleados (Zika y CHIKV) con posibilidad de amplificar cantidades menores a esta. En todos los casos se obtuvieron bandas nítidas e íntegras de acuerdo a los tamaños esperados haciendo uso de cepas previamente identificadas de DENV, CHIKV y Zika. La puesta en marcha de estas metodologías permitirá fortalecer el diagnóstico oportuno de miembros de estos géneros en el marco del sistema de vigilancia epidemiológica de enfermedades virales.

Flavivirus and alphavirus affect the health of humans. In Venezuela and particularly in Aragua, the communities have been affected by some members of these genus, such as dengue (DENV), and Chikungunya (CHIKV). DENV circulating in Aragua since 1989 generating outbreaks of clinical importance, while CHIKV made its appearance in 2014. In Aragua state, the diagnosis had been directed toward the detection of DENV, however the situation with CHIKV generates the need to expand the diagnosis spectrum to other viral agents. In the LARDIDEV we adapted two methodology of RT-PCR´s previously de scribed to detect members of these genus using flavivirus (DENV y Zika) and alphavirus (CHIKV) control strains. Both techniques were modified in the concentration of some reactants (MgCl2, dNTP´s, and primers) in the second reaction of PCR. The other conditions are kept equal to those originally described. Both techniques allowed amplified up to 1 fg of RNA of viral strains (Zika and CHIKV virus), but it could to amplify smaller amounts. In all cases, sharp bands according to the expected sizes using previously identified strains of DENV, CHIKV and Zika virus were obtained. The implementation of these methodologies will strengthen the timely diagnosis of members of this genus within the system of epidemiological surveillance of viral diseases.

Perfil clínico epidemiológico de embarazadas con chikungunya bajo vigilancia epidemiológica en corposalud, estado aragua. año 2014 / Clinical epidemiological profile of pregnant with chikungunya in corposalud watch in state epidemiological aragua 2014

Chikungunya en la mujer embarazada constituye un estado nosológico que pone en peligro la vida materno-infantil durante el periodo perinatal. Con el objetivo de determinar el perfil clínico epidemiológico de embarazadas con Chikungunya bajo vigilancia epidemiológica, se realizo un estudio descriptivo y epidemiológico retrospectivo con una muestra de fichas epidemiológicas de 100 embarazadas con Chikungunya durante el segundo semestre del año 2014.Los datos obtenidos fueron procesados y analizados utilizando medidas de tendencia central, porcentajes e intervalos de confianza. Los resultados indican un promedio de 27 años de edad, siendo el eje Metropolitano de la ciudad de Maracay el de mayor incidencia con 86% de los casos de la entidad federal. El promedio del tiempo de embarazo fue entre las semanas 36 y 40 en 30% de ellas. La red pública representó 53% de las referencias. Las manifestaciones clínicas incluyen fiebre 94%, artralgias 84%, cefalea 75%, erupción cutánea 64%, náuseas y vómitos 45% y 43% respectivamente y disminución sustancial del hematocrito. En la evolución de las gestantes con Chikungunya no se encontró un comportamiento distinto al de la triada clínica de la enfermedad. Se evidenció un buen control prenatal con un estándar normal de 6 controles prenatales. Un bajo porcentaje de las embarazadas ingresó a la unidad de cuidados intensivos. Las complicaciones más frecuentes fueron la preeclamsia grave y la amenaza de parto pretérmino. El mal llenado de las fichas e historias clínicas impidió conocer con detalle los avances significativos en la toma de decisiones con respecto a la enfermedad.

Chikungunya in pregnant women is a nosological state that endangers life maternal and child during the perinatal period. In order to determine the clinical and epidemiological profile of pregnant women with Chikungunya under epidemiological surveillance, descriptive and retrospective epidemiological study with a sample of 100 pregnant epidemiological chips with Chikungunya was conducted during the second half of the year 2014.Los data were processed and analyzed using measures of central tendency, percentages and confidence intervals. The results indicate an average of 27 years of age, being the Metropolitan axis of the city of Maracay the highest incidence with 86% of cases the federal entity. The average length of pregnancy was between weeks 36 and 40 in 30% of them. The public network represented 53% of the references. Clinical manifestations include fever 94%, arthralgia 84%, headache 75%, 64% rash, nausea and vomiting 45% and 43% respectively and substantially decreased hematocrit. In the evolution of pregnant women with Chikungunya a different triad clinical behavior of the disease was found. good prenatal care with a normal standard 6 prenatal visits was evident. A low percentage of pregnant entered the intensive care unit. The most frequent complications were severe preeclampsia and preterm labor. The poor completion of clinical histories and files kept detailed knowledge significant advances in making decisions regarding the disease.

El virus Chikungunya en Colombia: aspectos clínicos y epidemiológicos y revisión de la literatura / Chikungunya virus in Colombia: Clinical and epidemiological aspects, and literature review / Vírus chicungunha na Colômbia: aspectos clínicos e epidemiológicos e revisão da literatura

En años recientes, con el movimiento de las poblaciones y la globalización, algunas infecciones y enfermedades han cambiado su patrón endémico por uno epidémico; es el caso del virus chikungunya, un arbovirus reemergente que ha activado las alarmas mundiales. Según datos de los Centros para el Control y Prevención de Enfermedades (CDC), de los Estados Unidos, hasta enero del 2015 se habían detectado más de un millón de casos sospechosos y alrededor de treinta mil habían sido confirmados por laboratorio en 42 países del Caribe, Centroamérica, Suramérica y Norteamérica. Según el Instituto Nacional de Salud de Colombia, el número total de casos de esta infección confirmados por clínica era de 231.392; por laboratorio se habían confirmado 1.528 y había 3.848 casos sospechosos, para un total general de 236.768. En esta revisión se incluyen los siguientes aspectos de la infección por el virus chikungunya: virología, transmisión por vector, patogenia, epidemiología, manifestaciones clínicas, pruebas de laboratorio, medidas de prevención y perspectivas futuras.

In recent years, with the movement of populations and with globalization, some infections and diseases have changed from endemic to epidemic in certain regions. Such is the case of chikungunya virus (CHIKV), a re-emerging arbovirus that has triggered global alarm. According to the Center for Disease Control and Prevention (CDC), until January 2015, there had been case reports from 42 countries in the Caribbean, and Central, South, and North America, with more than one million suspected cases and about thirty thousand laboratory-confirmed cases. The latest report in Colombia by Instituto Nacional de Salud refers to a total of 231.392 clinically confirmed cases (suggestive symptoms associated with CHIKV), 1.528 cases confirmed by laboratory, and 3.848 suspected cases, for an overall total of 236.768. In this review, the following aspects of CHIKV infection are included: virology, transmission by vector, pathogenesis, epidemiology, clinical manifestations, laboratory tests, preventive measures and future prospects.

Nos anos recentes, com o movimento das populações e a globalização, algumas infecções e doenças mudaram seu padrão endémico por um epidêmico; é o caso do vírus chicungunha, um arbovírus reemergente que ativou os alarmes mundiais. Segundo dados do Centro para o Controle e Prevenção de Doenças (CDC), dos Estados Unidos, até janeiro de 2015 se tinham detectado mais de um milhão de casos suspeitos e ao redor de trinta mil tinham sido confirmados por laboratório em 42 países do Caribe, América Central, América do Sul e América do Norte. Segundo o Instituto Nacional de Saúde da Colômbia, o número total de casos desta infecção confirmados por clínica era de 231.392; por laboratório se tinham confirmado 1.528 e tinha 3.848 casos suspeitos, para um total geral de 236.768. Nesta revisão se incluem os seguintes aspectos da infecção pelo vírus chicungunha: virologia, transmissão por vector, patogenia, epidemiologia, manifestações clínicas, provas de laboratório, medidas de prevenção e perspectivas futuras.

Chikungunya: bending over the Americas and the rest of the world

Abstract Chikungunya is an arthropod-borne virus transmitted by Aedes mosquito bites. A viral mutation has allowed Aedes albopictus to become the preferred vector extending the geographic spread of the condition. The virus causes an acute febrile illness occasionally followed by a chronic rheumatic condition causing severe impairment. The diagnosis is usually confirmed with serology. No specific treatment is currently available. This article reviews the condition with emphasis on his dissemination in the Americas.