Seroprevalence of chikungunya virus infection in five hospitals within Anyigba, Kogi State of Nigeria

ABSTRACT Febrile illnesses in developing countries are often misdiagnosed as malaria or typhoid fever. Although arboviral infections have similar clinical symptoms, they are usually not screened because of limited resources and the fact that there are several viruses in this group. Chikungunya virus (CHIKV) has been isolated in parts of Nigeria, but there is no documented evidence of the infection in Kogi State. This study determined seroprevalence of active and past CHIKV infection among febrile patients who tested negative for malaria and typhoid fever. Sera from 243 febrile patients were screened for CHIKV IgG and IgM using an immunochromatographic test kit. Clinical and socio-demographic variables were collected using a structured questionnaire. Recent CHIKV infection was observed in 5.8% of the study participants while 25.1% had IgG antibodies demonstrating previous infection. Significant associations were observed between seropositivity and age of participants (p < 0.001), sex (p = 0.044), marital status (p = 0.002), and occupation (p < 0.001). Clinical symptoms such as fever, joint pain, and headache were significantly associated with seropositivity. This study identified recent CHIKV infection in Anyigba. Therefore, there is need for routine screening of febrile patients and molecular characterization to determine the nature of circulating strains.

Acute disseminated encephalomyelitis (ADEM) associated with mosquito-borne diseases: Chikungunya virus X yellow fever immunization

Abstract Acute disseminated encephalomyelitis (ADEM) is a demyelinating autoimmune neuropathic condition characterized by extensive bilateral and confluent lesions in the cerebral white matter and cerebellum. The basal ganglia and gray matter may also be involved. In most cases, the symptoms are preceded by viral infection or vaccination. In this report, we present a case of ADEM associated with optic neuritis presenting alongside two potential triggering factors: chikungunya virus infection and yellow fever immunization.

Chikungunya in a kidney transplant recipient: a case report / Chikungunya em um receptor de transplante renal: relato de caso

ABSTRACT In 2004, a global spread of Chikungunya fever affected most tropical and subtropical regions of the world. In 2016, an outbreak occurred in Northeast Brazil with hundreds of cases documented. Solid organ transplant recipients have a modified immune response to infection and the clinical course is usually different from immunocompetent patients. The diagnosis can be challenging in this population. Most reports describe patients residing in endemic areas, although we must emphasize the importance of differential diagnosis in kidney transplanted travelers who visit endemic regions, such as Northeast Brazil. Here, we reported a case of a kidney transplant recipient that acquired Chikungunya fever after a trip to an endemic region at Northeast Brazil during the outbreak in 2016, with a good clinical evolution. We also present warning recommendations for travelers to endemic areas as additional measures to prevent disease outbreaks.

RESUMO Em 2004, um surto global de Chikungunya afetou a maioria das regiões tropicais e subtropicais do mundo. Em 2016, um surto ocorreu no Nordeste do Brasil com centenas de casos documentados. Receptores de transplantes de órgãos sólidos têm uma resposta imune modificada à infecção, e o curso clínico é geralmente diferente daquele em pacientes imunocompetentes. O diagnóstico pode ser desafiador nessa população. A maioria dos relatos descreve pacientes residentes em áreas endêmicas, embora devamos enfatizar a importância do diagnóstico diferencial em viajantes transplantados renais que visitam regiões endêmicas, como o Nordeste do Brasil. Aqui, nós relatamos o caso de um receptor de transplante renal que adquiriu febre Chikungunya após uma viagem a uma região endêmica no Nordeste do Brasil durante o surto de 2016, com uma boa evolução clínica. Também apresentamos recomendações de alerta para viajantes em áreas endêmicas, como medidas adicionais para prevenir surtos de doenças.

Manifestações oculares na febre Chikungunya / Ocular Manifestations of Chikungunya Fever

Resumo A febre Chikungunya é um problema de saúde pública mundial, com potencial para gerar epidemias de alta morbidade, visto que elevado número de pacientes pode apresentar sequelas articulares prolongadas e alterações oftalmológicas. As manifestações oftalmológicas podem estar presentes na fase aguda da doença ou ter início após várias semanas da instalação do quadro. Na literatura mundial é descrito desde alterações mais comuns e de fácil tratamento como conjuntivites até alterações mais complexas e que podem cursar com sequelas visuais graves como a retinite e neurite óptica.

Abstract Chikungunya fever is a world public health problem with the potential to generate epidemics of high morbidity, since a high number of patients may present prolonged joint sequelae and ophthalmological alterations. Ophthalmologic manifestations may be present in the acute phase of the disease or begin after several weeks of the onset of the disease. In the world literature is described from more common and easy to treat changes such as conjunctivitis to more complex changes and that can occur with severe visual sequelae such as retinitis and optic neuritis.

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.

Dengue, zika, chikungunya y el desarrollo de vacunas / Dengue, zika, chikungunya and the development of vaccines

Dengue (DENV), zika (ZIKV) y chikungunya (CHIKV), tres arbovirosis transmitidas por mosquitos Aedes, se han propagado en las últimas décadas en zonas tropicales y subtropicales húmedas. El dengue es epidémico en áreas subtropicales de la Argentina. Después de la infección por DENV hay inmunidad duradera contra el serotipo infectante, pero aumenta el riesgo de enfermedad grave por los otros tres. La vacuna recombinante tetravalente, Dengvaxia® previene el dengue grave y la hospitalización en sujetos seropositivos. En 2017 se aprobó Dengvaxia en Argentina, para edades de 9 a 45 años, sin incluirla en el calendario nacional de vacunación. Otras dos vacunas se hallan en evaluación Fase III: la desarrollada por NIAID/ Instituto Butantan y la vacuna Takeda. ZIKV, virus asociado a microcefalia en recién nacidos en Brasil, circula desde 2016 en Argentina. Aún no existe vacuna de actividad comprobada contra ZIKV ni tratamiento eficaz. No se registró circulación activa de CHIKV en Argentina en 2017. Los brotes de fiebre CHIKV tienen una complicación: el desarrollo de reumatismo crónico post-enfermedad. No existen vacunas aprobadas para humanos ni terapias antivirales efectivas. La gravedad de estas virosis contribuyó a un rápido progreso en el conocimiento de los procesos de infección y de la respuesta inmune. Pero sus vectores, Aedes aegypti y A. albopictus, continúan expandiéndose, lo que indica que la vacuna será el medio más efectivo para el control. Se resume aquí información sobre estas arbovirosis en Argentina y Brasil, y se describen avances en el desarrollo y la evaluación de vacunas.

Dengue (DENV), zika (ZIKV) and chikungunya (CHIKV), three arbovirosis transmitted by Aedes mosquitoes, have spread in recent decades in humid tropical and subtropical zones. Dengue is epidemic in subtropical areas of Argentina. DENV infection confers lasting immunity against the infecting serotype but increases the risk of serious disease upon reinfection by any of the other three. The recombinant tetravalent vaccine Dengvaxia® prevents severe dengue and hospitalization in seropositive subjects. In 2017, Dengvaxia was approved in Argentina, for ages 9 to 45, but is not included in the national vaccination calendar. Two other vaccines are in Phase III evaluation: one developed by NIAID / Instituto Butantan and the other by Takeda.ZIKV, a virus associated with microcephaly in newborns in Brazil, circulates since 2016 in Argentina. There is still not effective treatment nor vaccine with proven activity against ZIKV. There has been no active circulation of CHIKV in Argentina in 2017. Outbreaks of CHIKV fever have a complication: the development of chronic post-disease rheumatism. There are not approved vaccines for humans nor effective antiviral therapies. The seriousness of these virosis has contributed to a rapid progress in the knowledge of the infection processes and the immune response. For now, Aedes aegypti and A. albopictus vectors continue to expand, suggesting that the vaccine will be the most effective means of controlling these viruses. Here we summarize information about these arbovirosis in Argentina and Brazil and describe advances in the development and evaluation of vaccines.

The hidden burden of Chikungunya in central Mexico: results of a small-scale serosurvey / La carga oculta de Chikungunya en el centro de México: resultados de una encuesta serológica a pequeña escala

Abstract: Objective: To estimate the seroprevalence of CHKV antibodies and assess correlates of seropositivity at a small geographical scale. Materials and methods: A community-based serosurvey of 387 households in Puente de Ixtla, Morelos (central Mexico). Serum IgG antibodies to CHKV were detected by immunoassay. Results: From 27 April to 29 May 2016, we interviewed and collected blood samples from 387 individuals at the same number of households. A total of 114 (29.5%) participants were seropositive to CHK, 36 (31.6%) of them reported no symptoms of CHKV infection within 12 months before the survey. Conclusion: The estimated seroprevalence to CHKV antibodies was higher than expected by the small number of confirmed cases of CHKV infection reported in Mexico by the National Surveillance System.

Resumen: Objetivo: Estimar la seroprevalencia de anticuerpos CHKV y evaluar correlatos de seropositividad a pequeña escala geográfica. Material y métodos: Encuesta serológica comunitaria en 387 hogares en Puente de Ixtla, Morelos (región central de México). Se detectaron anticuerpos IgG contra CHKV mediante inmunoensayo. Resultados: Del 27 de abril al 29 de mayo de 2016 se entrevistó a 387 individuos en el mismo número de hogares y se recolectaron muestras de sangre de los mismos. En total, 114 (29.5%) participantes fueron seropositivos a CHK, 36 (31.6%) de ellos negaron síntomas de infección por CHKV durante los 12 meses previos a la encuesta. Conclusión: La seroprevalencia estimada de anticuerpos contra CHKV; fue mayor a la esperada con base en el pequeño número de casos confirmados de infección por CHKV informados en México por el Sistema Nacional de Vigilancia.

Caracterização clínica das síndromes neurológicas durante a tríplice epidemia de arboviroses em Salvador, Bahia, Brasil / Clinical characterization of neurological syndromes during the triple arbovirus epidemic in Salvador, Bahia, Brazil

INTRODUÇÃO: Os arbovírus são vírus transmitidos por vetores artrópodes e diversos deles podem ser encontrados em cocirculação no Brasil. Complicações neurológicas associadas aos vírus dengue (DENV), chikungunya (CHIKV) e zika (ZIKV) já foram descritas anteriormente na literatura. Durante a tríplice epidemia de arboviroses houve um aumento importante de casos neurológicos, principalmente síndrome de Guillain-Barré (GBS).MATERIAL E MÉTODOS: Iniciada uma vigilância hospitalar para síndromes neurológicas agudas, onde foram incluídos pacientes avaliados em unidades neurológicas de dois hospitais de referência em Salvador/BA durante o período de maio de 2015 a abril de 2016.RESULTADOS: Cinco artigos foram escritos para melhor caracterização do tema. Dois casos de GBS clássico associado ao ZIKV foram publicados durante o surto supracitado, sendo um dos primeiros artigos no Brasil relacionando as duas doenças. Foi realizada a descrição com detalhes o caso da rara síndrome opsoclonus-mioclonusencefalite (OMAS), no qual a pacientes e apresentara com alteração de sensório, movimentos oculares anárquicos e ataxia. Na investigação foram detectados o DENV e CHIKV no plasma e o CHIKV no líquor pelo RTPCR.A paciente foi tratada com corticoide venoso e teve alta com melhora funcional, semalterações cognitivas ou motoras. Uma série de 5 casos descreveu com mais detalhe uma forma neurológica mais leve, a polineuropatia sensitiva reversível (RSP). Todos os pacientes apresentaram quadros transitórios, exclusivamente de alterações sensitivas; dois casos tinham evidência de infecção recente por ZIKV e outros 2 por CHIKV. Uma série de casos de pacientes com GBS, avaliou 14 indivíduos, sendo que 50% destes apresentavam variantes dessa doença. Havia uma maior prevalência de acometimento do nervo facial do que nas populações previamente estudadas. Prevaleceu a forma desmielinizante na eletroneuromiografia desses pacientes. Setenta e dois por cento dos pacientes foram reavaliados em 30 dias e todos tiveram ótima recuperação funcional. Por fim foi escrito um estudo de corte transversal que descreveu as síndromes neurológicas ocorridas em Salvador durante o surto da tríplice arboviral com 29 pacientes acompanhados; aproximadamente 50% se apresentaram com GBS ou suas variantes. Outras manifestações como encefalites, mielites, OMAS e RSP foram descritas. Cerca de 80% dos pacientes apresentavam evidência sorológica de infecção recente por ZIKV ou CHIKV. CONCLUSÃO: Foram descritas manifestações neurológicas como GBS e outras síndromes relacionadas às arboviroses. O melhor conhecimento dessas manifestações pode trazer benefício para prevenção, diagnóstico e tratamento dessas doenças, assim como melhorar as ações em saúde pública para combate às complicações por arboviroses

INTODUCTION: Arboviruses are viruses transmitted by arthropod vectors and several ofthem can be found in cocirculation in Brazil. Neurological complications associated with dengue virus (DENV), chikungunya (CHIKV) and zika (ZIKV) have previously been described in the literature. During the triple epidemic of arboviruses there was a significant increase in neurological cases, mainly Guillain-Barré syndrome (GBS). MATERIAL AND METHODS: A hospital surveillance for acute neurological syndromes was started, which included patients evaluated in neurological units of two reference hospitals in Salvador / BA during the period from May 2015 to April 2016. RESULTS: Five articles were written to better characterize the clinical manifestations. Two cases of classic GBS associated with ZIKV were published during triple arbovirosis outbreak, being one of the first articles in Brazil correlating the two diseases. A detailed description was made of the rare opsoclonus-myoclonus encephalitis syndrome (OMAS), in another article, in which the patient presented with confusion, anarchical ocular movements and ataxia. DENV and CHIKV were detected in plasma and CHIKV in the CSF by RT-PCR. The patient was treated with venous corticosteroids and was discharged with functional improvement, without cognitive or motor alterations. A series of 5 cases described a milder neurological form, the reversible sensory polyneuropathy (RSP). All patients presented only with transient sensory disturbances; two cases evidenced recent infection by ZIKV and another 2 by CHIKV. A case-series of GBS patients evaluated 14 individuals, with 50% of them presenting with GBS subtypes. There was a higher prevalence of facial nerve involvement than in the previously studied populations. The demyelinating form prevailed in the electroneuromyography studies of these patients. Seventy-two percent of the patients were reassessed in 30 days and all had an optimal functional recovery. Finally, a cross-sectional study was written and described the neurological syndromes that occurred in Salvador during the outbreak of the triple arboviral with 29 patients followed up; approximately 50% presented with GBS or its subtypes. Other manifestations such as encephalitis, myelitis, OMAS and RSP were described. About 80% of the patients had serological evidence of recent infection by ZIKV or CHIKV. CONCLUSION: Neurological manifestations such as GBS and other syndromes related to arbovirus have been described. The better knowledge of these manifestations can benefit the prevention, diagnosis and treatment of these diseases, as well as to improve the actions in public health to combat complications by arbovirosis

Potential role of dengue virus, chikungunya virus and Zika virus in neurological diseases

This study showed that laboratory markers of recent infection by dengue, Zika or chikungunya arboviruses were detected in the biological samples of approximately one-third of patients with encephalitis, myelitis, encephalomyelitis or Guillain-Barré syndrome, in a surveillance programme in Piauí state, Brazil, between 2015-2016. Fever and myalgia had been associated with these cases. Since in non-tropical countries most infections or parainfectious diseases associated with the nervous system are attributed to herpesviruses, enteroviruses, and Campylobacter jejuni, the present findings indicate that in tropical countries, arboviruses may now play a more important role and reinforce the need for their surveillance and systematic investigation in the tropics.

Development of in-house serological methods for diagnosis and surveillance of chikungunya / Desarrollo de métodos serológicos propios para el diagnóstico y la vigilancia del chikungunya

ABSTRACT Objective To develop and evaluate serological methods for chikungunya diagnosis and research in Nicaragua. Methods Two IgM ELISA capture systems (MAC-ELISA) for diagnosis of acute chikungunya virus (CHIKV) infections, and two Inhibition ELISA Methods (IEM) to measure total antibodies against CHIKV were developed using monoclonal antibodies (mAbs) and hyperimmune serum at the National Virology Laboratory of Nicaragua in 2014-2015. The sensitivity, specificity, predictive values, and agreement of the MAC-ELISAs were obtained by comparing the results of 198 samples (116 positive; 82 negative) with the Centers for Disease Control and Prevention's IgM ELISA (Atlanta, Georgia, United States; CDC-MAC-ELISA). For clinical evaluation of the four serological techniques, 260 paired acute and convalescent phase serum samples of suspected chikungunya cases were used. Results All four assays were standardized by determining the optimal concentrations of the different reagents. Processing times were substantially reduced compared to the CDC-MAC-ELISA. For the MAC-ELISA systems, a sensitivity of 96.6% and 97.4%, and a specificity of 98.8% and 91.5% were obtained using mAb and hyperimmune serum, respectively, compared with the CDC method. Clinical evaluation of the four serological techniques versus the CDC real-time RT-PCR assay resulted in a sensitivity of 95.7% and a specificity of 88.8%-95.9%. Conclusion Two MAC-ELISA and two IEM systems were standardized, demonstrating very good quality for chikungunya diagnosis and research demands. This will achieve more efficient epidemiological surveillance in Nicaragua, the first country in Central America to produce its own reagents for serological diagnosis of CHIKV. The methods evaluated here can be applied in other countries and will contribute to sustainable diagnostic systems to combat the disease.

RESUMEN Objetivo Elaborar y evaluar métodos serológicos para el diagnóstico y la investigación del chikungunya. Métodos Se elaboraron dos sistemas de ELISA de captura de IgM (MAC-ELISA por sus siglas en inglés) para el diagnóstico de la infección aguda por el virus de (CHIKV) y dos métodos de ELISA de inhibición (MEI) para determinar el valor cuantitativo de los anticuerpos totales contra el CHIKV, en el Laboratorio Nacional de Virología de Nicaragua en 2014-2015, para lo cual se utilizaron anticuerpos monoclonales (AcMo) y sueros hiperinmunes. Se determinó la sensibilidad, la especificidad y los valores predictivos, así como la concordancia de los MAC-ELISA, comparando los resultados de 198 muestras (116 positivas y 82 negativas) con el ELISA de los Centros para el Control y la Prevención de Enfermedades de los Estados Unidos (Atlanta; MAC-ELISA-CDC). Para la evaluación clínica de las cuatro técnicas serológicas, se emplearon 260 muestras de suero obtenidas en la fase aguda y en la fase de convalecencia de presuntos casos de chikungunya. Resultados Se estandarizaron los cuatro métodos analíticos determinando las concentraciones óptimas de los diferentes reactivos. La duración del procesamiento se redujo sustancialmente en comparación con el MAC-ELISA-CDC. Con los sistemas de MAC-ELISA, se obtuvo una sensibilidad del 96,6% y del 97,4% y una especificidad del 98,8% y del 91,5% al utilizar AcMo y suero hiperinmune, respectivamente, en comparación con el método de los CDC. La evaluación clínica de las cuatro técnicas serológicas, en comparación con la PCR en tiempo real de los CDC, arrojó una sensibilidad del 95,7% y una especificidad del 88,8%-95,9%. Conclusiones Se estandarizaron dos sistemas de ELISA-MAC y dos de MEI y se comprobó que poseen la calidad adecuada para el diagnóstico y las investigaciones del chikungunya, con lo cual mejorará la eficiencia de la vigilancia epidemiológica en Nicaragua, el primer país centroamericano que produce sus propios reactivos para el diagnóstico serológico del CHIKV. Los métodos estudiados en este trabajo pueden aplicarse en otros países y contribuyen al desarrollo de sistemas de diagnóstico sostenibles para combatir la enfermedad.

Seroprevalencia y tasa de ataque clínica por chikungunya en Nicaragua, 2014-2015 / Chikungunya seroprevalence and clinical case rate in Nicaragua, 2014-2015

RESUMEN Objetivo Estimar la seroprevalencia, la tasa de ataque clínica y la proporción de infecciones subclínicas por chikungunya, Métodos Se realizó un estudio transversal en 39 sitios distribuidos en todo el territorio nacional de Nicaragua en octubre 2015. Se recopiló información demográfica y clínica a través de una encuesta personal. Se recolectaron muestras hemáticas para detectar la presencia de anticuerpos antivirus chikungunya utilizando el método de ELISA de inhibición desarrollado por el Centro Nacional de Diagnóstico y Referencia. Se utilizaron modelos lineales generalizados y modelos de multinivel de Poisson en el análisis de los resultados. Resultados Se enrolaron 11 722 participantes mayores de dos años de edad y se procesaron 11 280 muestras. En el nivel nacional, la seroprevalencia fue de 32,8% (IC95% [intervalo de confianza de 95%]: 31,9-33,6), con una tasa de ataque clínica de 26,5% (IC95%: 25,7-27,3) y una proporción de infecciones subclínicas de 19,1% (IC95%: 17,8-20,4). Se observó variabilidad en la seroprevalencia de los 39 sitios, y los que presentaron mayor índice de infestación por el vector mostraron una mayor seroprevalencia. A nivel individual, esta fue más elevada en los participantes mayores de 11 años. Conclusión Este es el primer estudio sobre la seroprevalencia de chikungunya en América Latina continental desde su introducción, en el que se determinaron la prevalencia a nivel nacional, la tasa de ataque clínico y la proporción de infecciones subclínicas. El modelo utilizado, con una amplia participación comunitaria y el rol rector del Ministerio de Salud de Nicaragua, puede constituir un ejemplo para la realización de estudios similares en la región.

ABSTRACT Objective Estimate seroprevalence, clinical case rate, and proportion of subclinical infections from chikungunya. Methods A cross-sectional study was conducted in October 2015 at 39 sites distributed across Nicaragua. Demographic and clinical information was compiled through a personal survey. Blood samples were collected to detect chikungunya antibodies using the ELISA inhibition method developed by Nicaragua's National Diagnostic and Reference Center. Results were analyzed using generalized linear models and multilevel Poisson models. Results A total of 11 722 participants aged >2 years were enrolled and 11 280 samples were processed. National seroprevalence was 32.8% (95% CI [95% confidence interval]: 31.9-33.6), with a clinical case rate of 26.5% (95% CI: 25.7-27.3) and a proportion of subclinical infections of 19.1% (95% CI: 17.8-20.4). Seroprevalence varied among the 39 sites and was greater at sites with higher vector infestation indices. Individually, seroprevalence was higher in participants aged >11 years. Conclusion Since its introduction, this is the first study on chikungunya seroprevalence in continental Latin America to determine national prevalence, clinical case rate, and proportion of subclinical infections. The study model, employing broad community participation and leadership by the Ministry of Health of Nicaragua, can be an example for conducting similar studies in the region.

Dengue, Zika y Chikungunya / Dengue, Zika y Chikungunya

Los responsables de la actual pandemia de Chikungunya (alfavirus), dengue y Zika (flavivirus) son virus trasmitidos por artrópodos, arbovirus. Su importancia aumentó en las Américas en los últimos 20 años. Los vectores principales son Aedes aegypti y A. albopictus. La infección por dengue provee inmunidad duradera al serotipo específico y temporaria a otros tres. La posterior infección por otro serotipo determina mayor gravedad. Existe una vacuna contra dengue registrada, Dengvaxia (Sanofi Pasteur). Otras dos (Butantan y Takeda) comienzan la Fase III en 2016. La infección por Zika suele ser asintomática, o presentarse con exantema, conjuntivitis y fiebre no muy elevada. No existen vacunas ni tratamiento específico. Se puede transmitir por vía parental, sexual y por transfusión sanguínea. Se la ha asociado con microcefalia. Chikungunya causa artralgias prolongadas, con respuesta inmune persistente. Hay dos vacunas candidatas en Fase II. El diagnóstico directo del dengue se realiza por cultivo, RT-PCR y ELISA para detección del antígeno NS1; los métodos indirectos son ELISA-IgM (reacción cruzada con otros flavivirus), MAC-ELISA, y neutralización en placas, que diferencia los 4 serotipos DENV y otros flavivirus. Zika se diagnostica por RT-PCR y aislamiento del virus. El diagnóstico serológico presenta reacciones cruzadas con otros flavivirus. Para CHIKV se emplean cultivo y RT-PCR, MAC-ELISA y neutralización en placas. Contra Aedes se emplean larvicidas organofosforados (temefos), insecticidas organofosforados (malation y fenitrotion) y piretroides (permetrina y deltametrina). Puede haber resistencia. Los derivados vegetales son menos costosos y biodegradables, entre ellos el aceite de cetronela, que microencapsulado se preserva de la evaporación.

Arboviruses are transmitted by arthropods, including those responsible for the current pandemic: alphavirus (Chikungunya) and flaviviruses (dengue and Zika). Its importance increased in the Americas over the past 20 years. The main vectors are Aedes aegypti and A. albopictus. Dengue infection provides long lasting immunity against the specific serotype and temporary to the other three. Subsequent infection by another serotype determines more serious disease. There is a registered vaccine for dengue, Dengvaxia (Sanofi Pasteur). Other two (Butantan and Takeda) are in Phase III in 2016. Zika infection is usually asymptomatic or occurs with rash, conjunctivitis and not very high fever. There is no vaccine or specific treatment. It can be transmitted by parental, sexual and via blood transfusion. It has been associated with microcephaly. Chikungunya causes prolonged joint pain and persistent immune response. Two candidate vaccines are in Phase II. Dengue direct diagnosis is performed by virus isolation, RT-PCR and ELISA for NS1 antigen detection; indirect methods are ELISA-IgM (cross-reacting with other flavivirus), MAC-ELISA, and plaque neutralization. Zika is diagnosed by RT-PCR and virus isolation. Serological diagnosis cross-reacts with other flavivirus. For CHIKV culture, RT-PCR, MAC-ELISA and plaque neutralization are used. Against Aedes organophosphate larvicides (temephos), organophosphorus insecticides (malathion and fenitrothion) and pyrethroids (permethrin and deltamethrin) are usually employed. Resistance has been described to all these products. Vegetable derivatives are less expensive and biodegradable, including citronella oil, which microencapsulated can be preserved from evaporation.

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.

Tenosinovitis por virus Chikungunya / Tenosynovitis due to Chikungunya virus

Se presenta a la consulta un hombre proveniente de la República Dominicana con una tenosinovitis del extensor del dedo medio derecho; en la convalecencia inmediata, segunda curva febril luego de 48 horas de permanecer asintomático de una enfermedad febril aguda, y marcada astenia, exantema pruriginoso, poliartralgias con impotencia funcional y rigidez articular generalizada. Los exámenes bioquímicos no aportaron datos de interés para el diagnóstico. La serología para virus dengue fue negativa. La detección de IgM y de anticuerpos neutralizantes para virus Chikungunya (CHIKV) fueron positivos.

We report the case of a man from Dominican Republic who consulted for a tenosynovitis of the right middle finger extensor; in the immediate convalescence second febrile curve, after 48 hours of no symptoms of an acute febrile illness, with marked fatigue, itchy rash, polyarthralgia, functional impairment and general stiffness. Biochemical tests did not provide useful data for diagnosis. Dengue virus serology was negative. Detection of IgM and neutralizing antibodies (PRNT) for Chikundunya virus (CHIKV) were positive.

Fiebre Chikungunya / Chikungunya fever

Antecedentes: La fiebre Chikungunya es causada por un alfavirus (CHIKV) ARN pertene- ciente a la familia Togaviridae. Fue descrito en 1953, a partir de entonces se han presentado epidemias desde África, Asia y últimamente casos en las Antillas en América. Ante el riesgo de importación y transmisión del virus, esta entidad ha adquirido importancia, antes poco conocida en nuestro continente. La presente revisión bibliográfica tiene como objetivo la actualización de conocimientos acerca de la fiebre Chikungunya. El CHIKV es transmitido por dos vectores, Aedes aegypti y albopictus, los humanos son el reservorio principal en los periodos epidémicos. Después de 3 a 7 días de incubación, aparece la fiebre, artralgias, cefalea. Laboratorialmente, se observa trombocitope- nia leve, leucopenia con linfopenia. Los indivi- duos no infectados previamente están en riesgo de adquirir la infección y desarrollar la enfermedad, siendo los neonatos y los ancianos más propensos a desarrollar formas más graves. La transmisión de madre a hijo es frecuente en la viremia materna intraparto, y conduce a la infección. La mortalidad es baja, pero la artral- gia inflamatoria con artropatía/artritis destruc- tiva puede comprometer la calidad de vida del paciente afectado. Dada la introducción del CHIKV en la Región, la detección oportuna, una respuesta apropiada y rápida, son necesarias para minimizar el riesgo de importación y transmisión del CHIKV...(AU)

Chikungunya virus outbreak in Kerala, India, 2007: a seroprevalence study

India was affected by a major outbreak of chikungunya fever caused by Chikungunya virus (CHIKV) during 2006-2007. Kerala was the worst affected state during 2007 with a contribution of 55.8 percent suspected cases in the country. However, except for clinically reported case records, no systematic information is available on infection status of CHIKV in the region. Hence, we carried out a post-epidemic survey to estimate seroprevalence status [immunoglobulin G (IgG)] in the community using commercially available indirect immunofluorescence test. This methodology had been reported to be highly specific and sensitive for CHIKV infection. The study area selected was the worst affected mid-highlands region of Kerala which harbour vast area of rubber plantations. The study evidenced 68 percent of the population to be seropositive for CHIKV IgG. Males were found more affected than females (χ2 = 9.86; p = 0.002). Among males, prevalence was significantly higher in the age classes 21-30 (χ2 = 5.46; p = 0.019) and 31-40 (χ2 = 5.84; p = 0.016) years. This may be due to high occupational risk of the male population engaged in plantation activities exposed to infective bites of Aedes albopictus. The current study provides an insight into the magnitude of CHIKV outbreak in Kerala.

Chikungunya viral disease in district Bhilwara (Rajasthan) India.

An investigation of chikungunya outbreak cases was carried out in Bhilwara District, Rajasthan during Aug-Sep 2006. Fever with multiple joint pains was the first presenting feature. Aedes larval surveys indicate high Breteau index (78.6 to 200), House index (48.0 to 83.3) & Container index (41.1 to 73.6) above the critical index. Out of 40 sera samples tested, 12 showed HI antibodies for chikungunya virus in high titres and another five were positive for IgM antibodies against chikungunya. The clinico-epidemiological, laboratory and entomological investigations confirm that this episode of fever was due to chikungunya fever. Strengthening and intensification of surveillance along with educating the community were recommended for control of outbreak.

A serological study of Chikungunya virus transmission in Yogyakarta, Indonesia: evidence for the first outbreak since 1982.

A study of epidemic transmission of Chikungunya virus (CHIK) was initiated in April 1999 in Yogyakarta, Indonesia. Three hundred seventeen volunteers from three kelurahans (sub-districts) were recruited. Anti-CHIK IgG antibodies were detected in 68% to 74% of cases and 28% to 32% of controls. In the kelurahan with no reported CHIK illness, 29% of cases and 28% of controls had anti-CHIK IgG antibodies. None of these cases demonstrated anti-CHIK IgM antibodies. In the two kelurahans with disease activity, anti-CHIK IgM antibodies were detected in 3% to 36% of cases, with the highest percentage from the kelurahan with recently reported cases. Ten percent of controls from Gowok had anti-CHIK IgM detected in their serum. Twelve acutely ill volunteers were later included from the kelurahan Pilahan for virus identification. Samples from two volunteers were culture- and RT-PCR-positive for CHIK. This is the first documentation of epidemic transmission of CHIK in Indonesia since 1982.