ABSTRACT
This study aimed to assess anthropogenic impact of surrounding population in the Private Reserve of Natural Heritage at Pantanal, the world's largest freshwater wetland ecosystem located in the centre of South America. Viral aetiological agents of acute gastroenteritis as rotavirus A (RVA), noroviruses, human adenoviruses, klassevirus and of hepatitis, as hepatitis A virus, were investigated in different aquatic matrices. Annual collection campaigns were carried out from 2009 to 2012, alternating dry and rainy seasons. Viral particles present in the samples were concentrated by the adsorption-elution method, with negatively charged membranes, and detected by qualitative and quantitative PCR. From a total of 43 samples at least one virus was detected in 65% (28) of them. Viruses were detected in all matrices with concentrations ranging from 2 × 102 to 8·3 × 104 genome copies per litre. A significant higher RVA frequency was observed in the dry season. Our data revealing dissemination of human enteric viruses in water matrices both inside and outside the reserve could be useful to trace faecal contamination in the environment and to minimize the risk of infection by exposure of susceptible individuals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is part of a collaborative project designed to investigate the environmental and health conditions of the Private Reserve of Natural Heritage at Pantanal, the largest seasonally flooded wetland in the world. The project aimed to promote health and quality of human and wildlife extending technical-scientific knowledge about pathogens present in the region. By assessing the occurrence of human enteric viruses in different water matrices we demonstrated the anthropogenic impact of surrounding population and pointed out the potential risk of infection by exposure of susceptible individuals.
Subject(s)
Adenoviridae/isolation & purification , Enterovirus/isolation & purification , Gastroenteritis/virology , Hepatitis A virus/isolation & purification , Norovirus/isolation & purification , Parks, Recreational , Rotavirus/isolation & purification , Waterborne Diseases/virology , Adenoviridae/genetics , Antigens, Viral , Brazil/epidemiology , Ecosystem , Enterovirus/genetics , Feces/virology , Fresh Water/virology , Gastroenteritis/epidemiology , Hepatitis A virus/genetics , Humans , Norovirus/genetics , Rain/virology , Real-Time Polymerase Chain Reaction , Rotavirus/genetics , Seasons , Water Microbiology , Waterborne Diseases/epidemiologyABSTRACT
AIM: To determine the prevalence and molecular epidemiology of human sapovirus (SaV) in both wastewater and stool samples in a 3-year (2012-2014) surveillance study performed in Rio de Janeiro State, Brazil. METHODS AND RESULTS: A total of 156 wastewater and 341 stool samples were analysed using quantitative real-time PCR. SaV was detected in 3·5% (12/341) in stool samples with virus load concentrations ranging from 10(4) to 10(9) genome copies per gram (gc g(-1) ), and in 33·0% (51/156) wastewater samples, with range concentration varying from 10(4) to 10(6) gc l(-1) . Partial genome sequencing of wastewater and stool samples revealed the circulation of genotypes GI.1, GI.2, GI.6, GII.1 and GV.1. CONCLUSION: This study demonstrated the prevalence of human SaV in acute gastroenteritis (AGE) cases and revealed, for the first time, the environmental dissemination of those viruses in Brazil. SIGNIFICANCE AND IMPACT OF THE STUDY: SaV diagnosis should be considered in hospitalized children with AGE and the higher positive rate detection in environmental samples suggests that SaV infection could be underestimated or associated with asymptomatic cases.
Subject(s)
Caliciviridae Infections/virology , Feces/virology , Gastroenteritis/virology , Sapovirus/isolation & purification , Wastewater/virology , Adolescent , Brazil/epidemiology , Child , Child, Preschool , Female , Genotype , Humans , Infant , Male , Molecular Epidemiology , Phylogeny , Prevalence , Real-Time Polymerase Chain Reaction , Sapovirus/classification , Sapovirus/geneticsABSTRACT
A 4-year (2005-2008) norovirus (NoV) surveillance study was conducted in the state of Rio Janeiro, Brazil, to demonstrate the role of these viruses in outbreaks and sporadic cases of acute gastroenteritis. A cohort of 1,687 fecal samples was obtained from patients with gastroenteritis; 324 were rotavirus-positive. Of the remainder 1,363 rotavirus-negative samples, 1,087 samples were tested for NoV RNA in this study. The study enrolled 267 outpatients from Municipal Public Health Centers and 820 inpatients, whose samples were obtained by active surveillance in Public Hospitals. Fecal samples were tested by reverse transcription (RT) followed by polymerase chain reaction (PCR) using the MON 431-434 set of degenerate primers for NoV GI and GII detection, and there were 35.1% (381/1,087) positive samples for NoV, consisting of 30.2% (248/820) and 49.8% (133/267) from inpatient and outpatient, respectively. Children infected by NoV had significantly more frequent mucus in feces, vomiting and fever. No seasonal pattern in NoV infections was observed in patients admitted to hospital; however, two peaks of NoV infections were observed from ambulatory cases, suggesting that there was an occurrence of outbreaks in those time periods. Molecular characterization revealed GII to be the most prevalent genogroup, totaling 96.3% (104/108) of all sequences analyzed, and GII.4 was the genotype detected most frequently (80.7%), followed by GII.6, 3, 14, 7, and 8. Two GI strains, GI.2 and GI.3, were also observed. The number of outbreaks and sporadic cases described in this study highlights the need to implement diagnosis of NoV in surveillance laboratories.
