Microbial risk assessment in recreational freshwaters from southern Brazil

Viviane Girardi; Kristina D Mena; Suelen M Albino; Meriane Demoliner; Juliana S Gularte; Fernanda G de Souza; Caroline Rigotto; Daniela M Quevedo; Vania E Schneider; Suelen O Paesi; Patrick M Tarwater; Fernando R Spilki

doi:10.1016/j.scitotenv.2018.09.177

Microbial risk assessment in recreational freshwaters from southern Brazil

Sci Total Environ. 2019 Feb 15;651(Pt 1):298-308. doi: 10.1016/j.scitotenv.2018.09.177. Epub 2018 Sep 14.

Affiliations

¹ Laboratório de Microbiologia Molecular, Universidade Feevale, ERS 239, no 2755, Novo Hamburgo, RS 93352-000, Brazil. Electronic address: 0178103@feevale.br.
² School of Public Health, The University of Texas Health Science Center at Houston, El Paso, TX 79902, USA.
³ Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, no 2600, Porto Alegre, RS, Brazil.
⁴ Laboratório de Microbiologia Molecular, Universidade Feevale, ERS 239, no 2755, Novo Hamburgo, RS 93352-000, Brazil.
⁵ Laboratório de Vírus, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, no 6627, Belo Horizonte, MG, Brazil.
⁶ Programa de Pós-Graduação em Qualidade Ambiental, Universidade Feevale, ERS 239, no 2755, Novo Hamburgo, RS 93352-000, Brazil.
⁷ Instituto de Saneamento Ambiental (ISAM), Universidade de Caxias do Sul, Rua Francisco Getúlio Vargas, no 1130, Caxias do Sul, RS 95070-560, Brazil.
⁸ Laboratório de Diagnóstico Molecular, Instituto de Biotecnologia, Universidade de Caxias do Sul, Rua Francisco Getúlio Vargas, no 1130, Caxias do Sul, RS 95070-560, Brazil.
⁹ School of Public Health, Department of Biostatistics, The University of Texas Health Science Center at Houston, El Paso, TX 79902, USA.

PMID: 30240914
DOI: 10.1016/j.scitotenv.2018.09.177

Abstract

In this study, total coliforms (TC), Escherichia coli, enterovirus (EV), rotavirus (RV), and human mastadenovirus species C and F (HAdV-C and HAdV-F) were evaluated in water samples from Belo Stream. For HAdV-C and F, the infectivity was assessed by integrated cell culture quantitative real-time polymerase chain reaction (ICC-qPCR). Samples were collected monthly (May/2015 to April/2016) at four sites. Viral analyses were performed for both ultracentrifuge-concentrated and unconcentrated samples. For site P4 (used for recreational purposes), QMRA was applied to estimate health risks associated with exposure to E. coli and HAdV-C and F. TC and E. coli were present throughout the collection period. EV and RV were not detected. HAdV-C were present in 8.51% (1.89E + 06 to 2.28E + 07 GC (Genomic Copies)/L) and 21.27% (2.36E + 05 to 1.29E + 07 GC/L) for unconcentrated and concentrated samples, respectively. For HAdV-F were 12.76% (2.77E + 07 to 3.31E + 08 GC/L) and 48.93% (1.10E + 05 to 4.50E + 08 GC/L) for unconcentrated and concentrated samples, respectively. For unconcentrated samples, infectivity for HAdV-C was detected in 37.20% (1st ICC-qPCR) and 25.58% (2nd ICC-qPCR). For HAdV-F, infectivity was detected in 6.97% (1st ICC-qPCR) and 6.97% (2nd ICC-qPCR). For concentrated samples, HAdV-C infectious was observed in 17.02% (1st ICC-qPCR) and in 8.51% (2nd ICC-qPCR). For HAdV-F, were present in 8.51% for both 1st and 2nd ICC-qPCR. Statistical analyzes showed significant difference between the collection sites when analyzed the molecular data of HAdV-F, data of TC and E. coli. Correlation tests showed direct correlation between HAdV-F with E. coli and TC. E. coli concentrations translated to the lowest estimates of infection risks (8.58E-05 to 2.17E-03). HAdV-F concentrations were associated with the highest infection risks at 9.99E-01 and for group C, 1.29E-01 to 9.99E-01. These results show that commonly used bacterial indicators for water quality may not infer health risks associated with viruses in recreational freshwaters.

Keywords: Adenovirus; Escherichia coli; QMRA; Recreational waters; Viral infectivity; qPCR.

MeSH terms

Adenoviruses, Human / isolation & purification
Brazil
Enterobacteriaceae / isolation & purification
Enterovirus / isolation & purification
Escherichia coli / isolation & purification
Real-Time Polymerase Chain Reaction
Recreation
Risk Assessment*
Rivers / microbiology*
Rivers / virology
Rotavirus / isolation & purification
Water Quality*