Distribution and genetic diversity of the human polyomaviruses JC and BK in surface water and sewage treatment plant during 2009 in Porto Alegre, Southern Brazil / Distribuição e diversidade genética dos poliomavírus humanos JC e BK em águas superficiais e de estação de tratamento de esgoto durante 2009 em Porto Alegre, sul do Brasil

Abstract The human polyomaviruses JC and BK (JCPyV and BKPyV) are ubiquitous, species-specific viruses that belong to the family Polyomaviridae. These viruses are known to be excreted in human urine, and they are potential indicators of human wastewater contamination. In order to assess the distribution of both JCPyV and BKPyV in urban water samples collected from a sewage treatment plant (STP) and from a canalized water stream of Porto Alegre, Brazil, two nested-PCR assays were optimized and applied to the samples collected. The amplicons obtained were submitted to sequencing, and the sequences were analyzed with sequences of human polyomaviruses previously deposited in GenBank. Twelve out of 30 water samples (40%) were JCPyV positive, whereas six samples (20%) were BKPyV positive. The sequencing results confirmed the presence of JCPyV subtypes 1 and 3, whereas only BKPyV Ia and Ib were found. This study shows for the first time the presence of human polyomaviruses in surface water and in samples collected in a sewage treatment plant in southern Brazil.

Resumo Os poliomavírus humanos JC e BK (JCPyV e BKPyV) são virus ubíquos, espécie-específicos, pertencentes à família Polyomaviridae. Estes vírus são conhecidos por serem excretados pela urina humana, sendo considerados potenciais indicadores de contaminação por águas residuais urbanas. Buscando acessar a distribuição de JCPyV e BKPyV em amostras de águas coletadas de uma estação de tratamento de esgoto e de um arroio canalizado de Porto Alegre, Brasil, duas técnicas de nested-PCR foram otimizadas e aplicadas às amostras coletadas. Os amplificados obtidos foram submetidos ao sequenciamento e suas sequências analisadas com base em sequências de poliomavírus humanos previamente depositadas no GenBank. Doze de 30 amostras de água (40%) foram positivas para JCPyV, enquanto 6 amostras (20%) foram positivas para BKPyV. Os resultados do sequenciamento confirmaram a presença dos subtipos 1 e 3 de JCPyV, enquanto apenas os BKPyV Ia e Ib foram encontrados. Este estudo demonstra pela primeira vez a presença de poliomavírus humanos em águas superficiais e em amostras coletadas em uma estação de tratamento de esgoto na região sul do Brasil.

Desempeño de una laguna anaerobia con bafle divisor seguida de una laguna facultativa, posible afectación de la salud pública

Esta investigación tuvo como objetivo principal evaluar la eficiencia de la estación para tratamiento de aguas residuales de la ciudad Santa Fé do Sul (São Paulo) y definir posibles efectos en la salud pública producidos por la calidad del efluente final. Se realizó un estudio batimétrico de las lagunas de estabilización anaerobia con bafle divisor y facultativa para formar un perfil de acumulación de lodos; se monitoreó durante 24 horas consecutivas el afluente bruto y los efluentes de las lagunas para diagnosticar el comportamiento de la Estación. La eficiencia media de remoción de la demanda bioquímica de oxígeno fue del 89%, mayor que la mínima eficiencia exigida por la legislación brasilera vigente. La cantidad de coliformes fecales superó en gran medida los valores permitidos; sin embargo, la concentración de sólidos sedimentables cumplió a cabalidad con la norma ambiental presentando valores menores a 1,0 mL/L. Los resultados mostraron que la estación requiere labores de mantenimiento de la laguna anaerobia, así como mayor control operacional y mantenimiento más efectivos. Se evidenció la necesidad de implementar un sistema de pos tratamiento que garantice la reducción de los coliformes fecales del efluente final como medida para disminuir posibles riesgos a la salud pública en la zona de descarga y aguas abajo del punto de vertimiento final.

The main objective in this research was to evaluate the efficiency of the sewage treatment plant of Santa Fé do Sul city (São Paulo) and to define possible effects on public health produced by the final effluent quality. A bathymetric study of the anaerobic with baffle and facultative stabilization ponds was done in order to define the sludge accumulation profile; the raw influents and the lagoons effluents were monitored during 24 consecutive hours to diagnose the Plant performance. The average efficiency of the biochemical oxygen demand was 89%, higher than the minimum efficiency allowed by the Brazilian current legislation. The amount of fecal coliforms highly exceeds the permitted values; however the settleable solids concentration achieved the environmental regulation with values lower than 1, 0 mL/L. The results indicated that the station requires maintenance works at the anaerobic pond, a better operational control and more effective maintenance. It was shown the need to install a post treatment system to guarantee the reduction of the fecal coliforms at the final effluent as an action to diminish the public health possible risks in the discharge zone and downstream of the final dump point.