Occurrence and Genetic Diversity of Human Cosavirus in Sewage in Italy

Wastewater-based epidemiology applied at the building-level reveals distinct virome profiles based on the age of the contributing individuals

BACKGROUND

Human viruses released into the environment can be detected and characterized in wastewater. The study of wastewater virome offers a consolidated perspective on the circulation of viruses within a population. Because the occurrence and severity of viral infections can vary across a person's lifetime, studying the virome in wastewater samples contributed by various demographic segments can provide valuable insights into the prevalence of viral infections within these segments. In our study, targeted enrichment sequencing was employed to characterize the human virome in wastewater at a building-level scale. This was accomplished through passive sampling of wastewater in schools, university settings, and nursing homes in two cities in Catalonia. Additionally, sewage from a large urban wastewater treatment plant was analysed to serve as a reference for examining the collective excreted human virome.

RESULTS

The virome obtained from influent wastewater treatment plant samples showcased the combined viral presence from individuals of varying ages, with astroviruses and human bocaviruses being the most prevalent, followed by human adenoviruses, polyomaviruses, and papillomaviruses. Significant variations in the viral profiles were observed among the different types of buildings studied. Mamastrovirus 1 was predominant in school samples, salivirus and human polyomaviruses JC and BK in the university settings while nursing homes showed a more balanced distribution of viral families presenting papillomavirus and picornaviruses and, interestingly, some viruses linked to immunosuppression.

CONCLUSIONS

This study shows the utility of building-level wastewater-based epidemiology as an effective tool for monitoring the presence of viruses circulating within specific age groups. It provides valuable insights for public health monitoring and epidemiological studies.

First Human Cosavirus Detection From Cerebrospinal Fluid in Hospitalized Children With Aseptic Meningitis and Encephalitis in Iran

OBJECTIVE

Human cosavirus (HCosV) is a newly recognized virus that seems to be partly related to nonpolio flaccid paralysis and acute gastroenteritis in pediatric patients. However, the relationship between HCosV and diseases in humans is unclear. To assess an investigation for the occurrence of HCosV among pediatric patients involved in meningitis and encephalitis, we implemented a real-time quantitative polymerase chain reaction assay for detection and quantification of HCosV in stool specimens.

MATERIALS AND METHODS

In this study, a total of 160 cerebrospinal fluid samples from September 2019 to October 2020 were collected from presenting pediatric patients with meningitis and encephalitis in a Karaj hospital, Iran. After viral RNA extraction, the real-time quantitative polymerase chain reaction was performed to amplify the 5'Un-Translated Region region of the HCosV genome and viral load was analyzed.

RESULTS

Of the 160 samples tested, the HCosV genomic RNA was detected in 2/160 (1.25%) of samples. The minimum viral load of HCosV was 3.5 × 103 copies/mL from 4 years male patient. The maximum viral load was determined to be 2.4 × 105 copies/mL in one sample obtained from 3.5 years female patient.

CONCLUSIONS

This is the first documentation of HCosV detection in cerebrospinal fluid samples that better demonstrates relation of HCosV with neurologic diseases including meningitis and encephalitis. Also, these results indicate that HCosV has been circulating among Iranian pediatric patients.

HUMAN COSAVIRUS INFECTION IN HIV SUBJECTS WITH DIARRHOEA: PERSISTENT DETECTION ASSOCIATED WITH FATAL OUTCOME

BACKGROUND

Human cosavirus (HCoSV) is a new member of the Picornaviridae family, geographically widespread among humans. It has been suggested as a causative agent of acute gastroenteritis, but its pathogenicity is not currently certain. In HIV-infected subjects, diarrhoea is one of the most frequent gastrointestinal manifestations, whose aetiology remains often unexplained.

OBJECTIVES

To identify the cause of viral diarrhoea among HIV infected patients by molecular assays.

STUDY DESIGN

A total of 143 stool samples from HIV subjects with and without diarrhoea, were screened for conventional enteric viruses (rotavirus, adenovirus, norovirus and astrovirus) by molecular assays. The presence of HCoSV genome was investigated by nested RT-PCR for the 5'UTR region. Positive samples were further characterized by sequencing and phylogenetic analysis.

RESULTS

Enteric viruses were more frequently found in diarrhoea cases (9/82) than controls (0/61) (p=0.007). HCoSV was detected in five (3.5%) of the subjects affected by diarrhoea. Phylogenetic analysis revealed the predominance of the HCoSV species D. One patient suffered a persistent cosavirus infection with a same strain and after eight months he had a fatal outcome. No other pathogens could be detected.

CONCLUSIONS

The results suggest a role of non-conventional enteric viruses, as HCoSV, as a potential opportunistic agent causing persistent infection and deterioration of the clinical conditions in HIV-infected patients. Screening procedures and monitoring including such viruses would be helpful in the clinical management of such patients.

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.

Molecular detection of cosaviruses in a patient with acute flaccid paralysis and in sewage samples in Germany

Cosaviruses (CoSV) were first identified in stool samples collected from non-polio acute flaccid paralysis (AFP) cases and their healthy contacts in Pakistan in 2003. The clinical importance of CoSV remains unclear as data on epidemiology are scarce and no routine diagnostic testing is done. In this study, we characterized human CoSV (HCoSV) in a child with non-polio AFP and in sewage samples collected in Berlin, Germany. Using unbiased high-throughput sequencing and specific PCR, we characterized a HCoSV-D in stool samples of a three-year-old child hospitalized in Germany with non-polio AFP and travel history to Pakistan. The shedding pattern and absence of other relevant pathogens suggests that HCoSV-D may have been involved in the genesis of AFP. The HCoSV-RNA concentration was high, with 2.57 × 10⁶ copies per mL fecal/suspension, decreasing in follow-up samples. To investigate the possibility of local circulation of HCoSV, we screened Berlin sewage samples collected between 2013 and 2018. Molecular testing of sewage samples has shown the presence of CoSV in several parts of the world, but until now not in Germany. Of our sewage samples, 54.3 % were positive for CoSV, with up to three viral species identified in samples. Phylogenetically, the German sequences clustered intermixed with sequences obtained globally. Together, these findings emphasize the need for further clinical, epidemiological, environmental, pathogenicity and phylogenetic studies of HCoSV.

Molecular Detection of Human Salivirus in Italy Through Monitoring of Urban Sewages

Salivirus (SalV) is a newly discovered virus associated to acute gastroenteritis in humans. In Italy, its prevalence and genetic diversity is unknown. To reduce this knowledge gap, 124 sewage samples collected throughout the country were analyzed for SalV by two nested RT-PCRs targeting the 5'UTR and the 3D regions and by real-time RT-qPCR. Virus RNA was detected in 37 (29.8%) samples; of these, 24 could be characterized and all belonged to genotype A1. Viral concentrations ranged between 2.8 × 10³ and 1.9 × 10⁵ genome copies per liter. This is the first report of SalV occurrence in water environments in Italy, suggesting that SalV infection is not uncommon in this country.

Typing of Human Cosaviruses by sequencing of full VP1: Update on global genetic diversity and identification of possible new genotypes circulating in Tunisia, North Africa

Human Cosaviruses (HCoSVs) are relatively newly characterized picornaviruses; they have been described in non-polio acute flaccid paralysis, diarrheal patients, and healthy individuals. Previous studies showed HCoSV circulation in Tunisia and only six genotypes circulating in the country were reported. In the present study, we sequenced 27 complete VP1 genomic region from HCoSV isolates in human feces from healthy individuals and patients with acute flaccid paralysis in Tunisia. Most of the Tunisian sequences belong to species A (78%, 21 out of 27). Three sequences belong to species B, two to species E and one sequence to species D. The Tunisian sequences belonged to genotype A6, A7, A8, A10, A1, A17 and E2. Based on genetic distance criteria for assigning genotypes corresponding to neutralization serotypes in enteroviruses we also identified 4 new HCoSV genotypes named A25, B2, B3 and D6. Our study updates the genetic classification of HCoSVs, proposes new genotypes within species A, B and D and contributes to a better knowledge of the HCoSV circulation throughout the world.