Persistent Detection of Cosavirus and Saffold Cardiovirus in Riachuelo River, Argentina.

Cosaviruses (CoSV) and Saffold cardiovirus (SAFV) are novel members of the Picornaviridae family. The Matanza-Riachuelo river basin covers a total area of 2200 km2 with approximately 60 km long. Its last section is called Riachuelo River. The aim of this study was to describe the circulation of both picornaviruses and their relationship with the environmental situation of the Riachuelo River using 274 samples collected from 2005 to 2015. CoSV and SAFV were investigated in samples available by two periods: 2005-2006 and 2014-2015 (103 and 101, respectively). Physicochemical and bacteriological parameters confirmed very high levels of human fecal contamination during the 11 years evaluated. CoSV was detected in 85.7% (66/77) and 65.4% (17/26) of the samples collected in 2005-2006 and 2014-2015 periods, respectively. Species A and D were identified, the first one being widely predominant: 74.1% (20/27) and 75.0% (3/4) in both periods. SAFV virus was detected in 47.1% (32/68) and 52.6% (10/19) in periods 2005-2006 and 2014-2015, respectively. SAFV-6 was the most identified genotype in the entire study, while SAFV-3 was predominant in 2005-2006. The contribution of genotypes 1, 2, 4 and 8 was minor. The high prevalence of CoSV and SAFV suggests that both viruses have been circulating in Argentina at least since 2005. Our results show that a watercourse with high rates of human fecal contamination can become a persistent source of new viruses which capacity to produce human diseases is unknown.

High diversity of human polyomaviruses in environmental and clinical samples in Argentina: Detection of JC, BK, Merkel-cell, Malawi, and human 6 and 7 polyomaviruses.

New human polyomaviruses have been recently described. The aim of this work was to detect and characterize human polyomaviruses circulating in Argentina by recovering viruses from environmental and sewage samples and evaluating their potential role as viral indicators of human waste contamination. Analysis was performed in a wider context including viruses from clinical samples from an immunocompromised population. River water and sewage samples were analyzed as a strategy to study the molecular epidemiology of viruses excreted by millions of people. Samples belonged to the Matanza-Riachuelo River (2005-2006: n=25 and 2012: n=20) and sewage from Buenos Aires city and suburbs (2011 and 2013: n=24). Viral detection was performed by PCR and the amplified viral genomes were characterized by phylogenetic analysis. Polyomaviruses were detected in 95.8% of sewage samples, identifying BKPyV (87.5%), JCPyV (83.3%), MCPyV (8.3%) and HPyV6 (8.3%). Besides, one sample collected in 2009 resulted positive for HPyV7. In 2005-2006, polyomaviruses were detected in 84.0% of river water samples, with the highest detection for MCPyV (52.0%), followed by BKPyV (44.0%), JCPyV (20.0%) and MWPyV (4.0%). In 2012, polyomaviruses were detected in 85.0% of river samples, finding JCPyV (85.0%), BKPyV (75.0%), MCPyV (25.0%) and HPyV6 (25.0%). Also, polyomaviruses, including JCPyV, BKPyV and MCPyV, were detected in 63.2% of urine samples from patients infected with HIV (n=19). Characterization indicated the coexistence of different genotypes and variants for each virus, particularly in sewage. MCPyV sequences (the only sequences from Argentina) formed a monophyletic group with the single sequence available for South America (French Guiana). The high level of detection and viral diversity found by environmental surveillance, which involved the characterization of viruses not previously described in South America, reinforces the usefulness of this approach to monitor viral contamination and describe the viral epidemiology in the general population.

[Analysis of an outbreak of viral meningitis in the province of Tucuman, Argentina]. / Análisis de un brote de meningitis viral en la provincia de Tucumán, Argentina.

OBJECTIVE: To confirm the occurrence of an outbreak of viral meningitis in 1996 in the province of Tucuman, Argentina, and to study the outbreak's epidemiological characteristics. METHODS: We analyzed information from the National Epidemiological Surveillance System of the Ministry of Health (MOH) of Argentina for 1994-1998 that had been provided by the MOH's Bureau of Epidemiology. We calculated incidence rates using population estimates for the years 1994-1998 developed by the National Statistics and Census Institute, based on the 1991 census. We studied frequencies with contingency tables, using the chi-square method with Yates' correction. Results were considered significant when P < 0.05. RESULTS: We confirmed the occurrence of an outbreak of 189 cases of viral meningitis between 11 February and 18 May 1996. The incidence of cases in Tucuman province increased between 1995 and 1996, from 0.5 to 19.3 cases per 100 000 person-years. That 1996 rate in Tucuman was significantly higher than what was seen in the rest of the country (2.8 cases per 100 000 person-years). Of the 189 cases, 142 of them (75.1%) occurred in children less than 9 years old. Out of 111 samples studied, 65 of them (58.6%) were enterovirus-positive. Through reverse transcription-nested polymerase chain reaction, enteroviruses were found in 66.3% (53/80) of the cases studied by this method, versus in only 29.6% (24/81) of the cases studied through viral isolation. In the 22 samples that were serotyped, echovirus type 4 was identified in 15 of them (68%): 5 by isolation, 3 by sequencing, and 7 by both methods. During the Tucuman outbreak, at least 56% of the cases were hospitalized. This viral meningitis outbreak shows the capacity of enteroviruses to spread and cause disease. CONCLUSIONS: The use of molecular methods makes it possible to rapidly diagnose the etiological virus and to better control an outbreak. Recognizing this outbreak in Tucuman sooner could have averted the majority of the hospitalizations and the indiscriminate use of antibiotics.

Análisis de un brote de meningitis viral en la provincia de Tucumán, Argentina / Analysis of an outbreak of viral meningitis in the province of Tucuman, Argentina

OBJETIVO: Confirmar la existencia de un brote de meningitis viral en 1996 en la provincia de Tucumán, Argentina, y estudiar sus características epidemiológicas. MÉTODOS: Se analizó información obtenida del Sistema Nacional de Vigilancia Epidemiológica (SINAVE) del Ministerio de Salud de Argentina para el período de 1994-1998, la cual fue provista por la Dirección de Epidemiología de dicho ministerio. Para el cálculo de incidencias se usaron estimaciones poblacionales para los años 1994-1998 realizadas por el Instituto Nacional de Estadística y Censos (INDEC) sobre la base del censo de 1991. El estudio de frecuencias se realizó mediante el análisis de tablas de contingencia de doble entrada, según el método de ji cuadrado con la corrección de Yates. Se consideró significativo el resultado cuando P < 0,05. RESULTADOS: Se confirmó la presencia de un brote de 189 casos entre el 11 de febrero y el 18 de mayo de 1996. La incidencia de casos en la provincia mostró un aumento entre 1995 y 1996 (de 0,5 a 19,3 casos por 100000 años-persona) y dicha incidencia fue significativamenrte mayor que la observada en el resto del país (19,3 frente a 2,8 casos por 100000 años-persona). El 75,1 por ciento de los casos ocurrió en niños menores de 9 años (142/189). Se detectó la presencia de Enterovirus (EV) en 65 de las 111 muestras estudiadas (58,6 por ciento). Mediante la reacción en cadena de la polimerasa (RCP) anidada con transcripción inversa se logró detectar EV en 66,3 por ciento (53/80) de los casos estudiados por este método, en comparación con solo 29,6 por ciento (24/81) de los estudiados mediante aislamiento viral. Se identificó echovirus tipo 4 en 15 (68 por ciento) en las 22 muestras tipificadas (5 por aislamiento, 3 por secuenciación y 7 por ambos métodos). Este brote demuestra la capacidad de los EV para diseminarse y producir enfermedad en la población. Durante el brote, por lo menos 56 por ciento de los casos fueron hospitalizados. CONCLUSIONES: El uso de métodos moleculares permitió el diagnóstico rápido del virus etiológico y posibilitó un mejor control del brote. El reconocimiento temprano de este podría haber evitado la mayoría de las hospitalizaciones y el uso indiscriminado de antibióticos