Distribution and molecular characterization of saffold virus and human cosavirus in children admitted to hospitals with acute gastroenteritis in Thailand, 2017-2022.

Saffold virus (SAFV) and human cosavirus (HCoSV) are emerging viruses of the Picornaviridae family. They have been shown to associate with gastrointestinal infection and more recently these viruses have also been demonstrated to associate with other clinical infections such as the respiratory tract, cardiovascular system, and the cerebral ventricular system. In this study, 2459 stool specimens collected from pediatric patients admitted to hospitals with acute gastroenteritis from January 2017 to December 2022, were screened for SAFV and HCoSV utilizing reverse transcription-polymerase chain reaction. Positive samples were then characterized into genotypes via nucleotide sequencing and bioinformatic analysis. Of the 2459 samples, 21 and 39 were positive for SAFV (0.9%) and HCoSV (1.6%), respectively. Three genotypes of SAFV were identified-SAFV-1 (38%), SAFV-2 (24%), and SAFV-3 (38%). Two genetic groups of HCoSV were identified-HCoSV-C (97%) and HCoSV-A (3%), demonstrating a large increase of HCoSV-C as compared to those reported previously from the same geographical region in Thailand. This study provides the prevalence of SAFV and HCoSV genotypes in Chiang Mai, Thailand during a period of 6 years from 2017 to 2022.

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.

Bufavirus, Cosavirus, and Salivirus in Diarrheal Italian Infants.

Three newly discovered viruses have been recently described in diarrheal patients: Cosavirus (CosV) and Salivirus (SalV), 2 picornaviruses, and bufavirus (BuV), a parvovirus. The detection rate and the role of these viruses remain to be established in acute gastroenteritis (AGE) in diarrheal Italian infants. From November 2016 to November 2017, stool samples were collected from 160 children <5 years old suffering from AGE and attending the Children's Hospital in Turin, Italy. During the study period, 1 (0.5%) sample was positive for 1 of the 3 investigated viruses: 0 (0%) CosV, 1 (0.5%) SalV, and 0 (0%) BuV, whereas 42 (26.0%) children were infected with rotavirus and 2 (1%) with adenovirus. No mixed infections involving the 3 viruses were found. Although these viruses are suspected to be responsible for AGE in children, our data showed that this association was uncertain. Therefore, further studies with large cohorts of healthy and diarrheal children will be needed to evaluate their clinical role in AGE.

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.

Global Status of Bufavirus, Cosavirus, and Saffold Virus in Gastroenteritis: A Systematic Review and Meta-Analysis.

Background: Bufavirus (BuV), Human Cosavirus (HCoSV), and Saffold (SAFV) virus are three newly discovered viruses and have been suggested as possible causes of gastroenteritis (GE) in some studies. The aim of the present study was to estimate the overall prevalence of viruses and their association with GE. Methods: A comprehensive systematic search was conducted in Scopus, Web of Science, PubMed, and Google scholar between 2007 and 2021 to find studies on the prevalence of BuV, HCoSV, and SAFV viruses. Result: Meta-analysis of the 46 included studies showed the low prevalence of BuV (1.%, 95% CI 0.6-1.5%), HCoSV (0.8%, 95% CI 0.4-1.5%), and SAFV (1.9%, 95% CI 1.1-3.1%) worldwide. Also, no significant association between these viruses and GE was observed. BuV was isolated from patients with GE in Africa, while SAFV was more common in Europe. BuV1 and BuV2 have the same prevalence between the three identified genotypes of BuV. HCoSV-C was the most prevalent genotype of HCoSV, and SAFV2 was the commonest genotype of SAFV. All of these viruses were more prevalent in children older than 5 years of age. Conclusion: This was the first meta-analysis on the prevalence and association of BuV, HCoSV, and SAFV with GE. While no significant association was found between infection with these viruses and GE, we suggest more studies, especially with case-control design and from different geographical regions in order to enhance our knowledge of these viruses.

High viral load detection of human Cosavirus in Iranian pediatric patients with acute gastroenteritis.

AIM: The present study implemented an RT-qPCR assay for the detection and quantification of human cosavirus in stool specimens from pediatric patients involved in acute gastroenteritis. BACKGROUND: Human cosavirus is a newly recognized virus that seems to be partly related to acute gastroenteritis in pediatric patients. However, the relationship between human cosavirus and diseases in humans is unclear. METHODS: From January 2018 to December 2019, a total of 160 stool samples were collected from pediatric patients presenting with acute gastroenteritis in a hospital in Karaj, Iran. After viral RNA extraction, RT-qPCR was performed to amplify the 5'UTR region of the human cosavirus genome and viral load was analyzed. RESULTS: The human cosavirus genomic RNA was detected in 4/160 (2.5%) stool samples tested. The maximum viral load was determined to be 4.6×106 copies/ml in one sample obtained from a 4-year-old patient. CONCLUSION: The human cosavirus as a new member of the Picornaviridae family was illustrated in fecal samples from pediatric patients with acute gastroenteritis in Iran. This is the first documentation of human cosavirus circulation in Iranian children.

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.

Near-complete genome of cosavirus A from a child hospitalized with acute gastroenteritis, Brazil.

Acute gastroenteritis (AG) is responsible for 525,000 deaths worldwide in children under-5-years and is caused by the Human Cosavirus (HCoSV; family Picornaviridae, Genus Cosavirus). Although its health importance, a significant percentage of diarrhea cases (≈ 40 %) still of unknown etiology. In Brazil, few studies have reported HCoSV-A sequences analyzing partial 5' UTR. This study characterized the first near-complete genome of a Cosavirus A (strain AM326) from a child hospitalized with AG in Amazonas state, Northern Brazil. High throughput sequencing (HTS) was performed using the HiSeq™ 2500 platform (Illumina) in one fecal specimen collected from the Surveillance of Rotavirus Network of the Evandro Chagas Institute collected in 2017. Sequence reads were assembled by the De Novo approach using three distinct algorithmic (IDBA-UD, Spades, and MegaHit). The final contig was recovered from the HCoSV-AM326 sample revealing 7,735 nt in length (SRA number SRR12535029; GenBank MT023104) and the genetic characterization, as well as phylogenetic analysis demonstrated a new variant strain from Brazil, highlighting the association of HCoSV-A as a possible causative agent of AG. This finding demonstrates the importance of the metagenomic approach to elucidate cases of diarrhea without a defined etiology, as well as providing a better understanding about the virus genetics, evolution and epidemiology.

Molecular Characterization and Clinical Description of Non-Polio Enteroviruses Detected in Stool Samples from HIV-Positive and HIV-Negative Adults in Ghana.

In the post-polio eradication era, increasing attention is given to non-polio enteroviruses. Most of the data about enteroviruses in sub-Saharan Africa are related to acute flaccid paralysis surveillance and target the pediatric population. This study aimed to investigate the presence of enterovirus in PLHIV (people living with HIV) and HIV-negative individuals in Ghana. Stool samples from HIV-positive individuals (n = 250) and healthy blood donors (n = 102) attending the Komfo Anokye Teaching Hospital in Kumasi, Ghana, were screened by real-time PCR for enterovirus. Molecular typing of the VP1 region was performed. Enterovirus-positive samples were tested for norovirus, adenovirus, rotavirus, sapovirus, and cosaviruses. Twenty-six out of 250 HIV-positive subjects (10.4%) and 14 out of 102 HIV-negative individuals (13.7%) were detected enterovirus-positive, not showing a significant different infection rate between the two groups. HIV-negative individuals were infected with Enterovirus C strains only. HIV-positive participants were detected positive for species Enterovirus A, Enterovirus B, and Enterovirus C. Co-infections with other viral enteric pathogens were almost exclusively detected among HIV-positive participants. Overall, the present study provides the first data about enteroviruses within HIV-positive and HIV-negative adults living in Ghana.

Molecular detection of enteric viruses in the stool samples of children without diarrhea in Bangladesh.

A number of molecular epidemiological studies reported the detection of enteric viruses in asymptomatic children. The role of these viruses in an asymptomatic infection remains unclear. This study investigated the enteric viruses in the stool samples collected from children without diarrhea. Stool samples were collected during June to October 2016, from 227 children who lived in Matlab, Bangladesh. Seventeen enteric viruses, including rotavirus A, B, and C (RVA, RVB, and RVC), norovirus GI (NoV GI), norovirus GII (NoV GII), sapovirus (SaV), adenovirus (AdV), human astrovirus (HAstV), Aichivirus (AiV), human parechovirus (HPeV), enterovirus (EV), human bocavirus (HBoV), Saffold virus (SAFV), human cosavirus (HCoSV), bufavirus (BufV), salivirus (SalV), and rosavirus (RoV), were investigated by RT-PCR method. One hundred and eighty-two (80.2%; 182/227) samples were positive for some of these viruses, and 19.8% (45/227) were negative. Among the positive samples, 46.7% (85/182) were a single infection, and 53.3% (97/182) were coinfection with multiple viruses. The HCoSV was the most prevalent virus (41.4%), followed by EV (32.2%), NoV GII (25.6%), HPeV (8.8%), RVA (6.2%), AdV (5.7%), AiV (5.3%), SAFV (4.4%), and SaV (2.6%). Each of NoV GI, HAstV, HBoV, and BufV was detected at 0.4%. However, RVB, RVC, SalV, and RoV were not detected in this study. Phylogenetic analysis showed that diverse HCoSV species and genotypes were circulating in Bangladesh, and four strains of species A are proposed to be new genotypes. The data indicated that non-diarrheal Bangladeshi children were asymptomatically infected with wide varieties of enteric viruses.

Occurrence and Genetic Diversity of Human Cosavirus in Sewage in Italy.

Human Cosavirus (HCoSV) is a newly discovered virus whose role in human enteric diseases is still unknown. In Italy, the prevalence and genetic diversity of HCoSV are unexplored. One hundred forty-one raw sewage samples collected throughout Italy were screened for HCoSV by RT-nested PCR. HCoSV was detected in 25.5% of samples. Species A, C, and D, and a potentially new species were detected. Our results show a significant circulation and heterogeneity of HCoSV in Italy.

Prevalence of human cosavirus and saffold virus with an emergence of saffold virus genotype 6 in patients hospitalized with acute gastroenteritis in Chiang Mai, Thailand, 2014-2016.

Human cosavirus and saffold virus are both newly discovered members of the Picornaviridae family. It has been suggested that these viruses may be the causative agents of acute gastroenteritis. In this study, 1093 stool samples collected from patients with acute gastroenteritis between January 2014 and December 2016, were screened for cosavirus and saffold virus using reverse transcription-polymerase chain reaction. The viral genotypes were then established via nucleotide sequencing. Here, cosavirus was detected in 16 of 1093 stool samples (1.5%) and saffold virus was detected in 18 of 1093 stool samples (1.6%). The saffold virus genotypes 1 (16.7%), 2 (50%) and 6 (33.3%), and the cosavirus genetic groups A (87.5%), C (6.25%) and D (6.25%), were all identified across the three-year study period. Interestingly, saffold virus genotype 6 has now been detected for the first time in Thailand. The present study provides the prevalence of cosavirus and saffold virus with the emergence of saffold virus genotype 6 in Thailand.

Identification of a novel cosavirus species in faeces of children and its relationship with acute gastroenteritis in China.

OBJECTIVES: To assess the prevalence of human cosavirus (HCosV) in China and to determine the association of a novel HCosV (Cosa-CHN) with acute gastroenteritis (AGE). METHODS: A case-control study with 461 paired stool samples from diarrhoea and healthy children was conducted. Real-time PCR and nested PCR were used to detect the HCosVs. Rapid amplification of cDNA ends was used to obtain the ends of the Cosa-CHN. RESULTS: Known HCosVs were detected in two control samples, while Cosa-CHN was detected in eight (1.7%) and six (1.3%) of the case and control samples respectively. The complete genome of Cosa-CHN comprises 7213 bp. The P1 and P2 regions of the Cosa-CHN were closely related to those of HCosV B, while the P3 region was most similar to that of HCosV D, albeit with low amino acid identities (66 and 67% respectively). Phylogenetic analyses of the polyprotein and partial VP3/VP1 regions indicated that Cosa-CHN could be classified as a novel species (tentatively named HCosV G) in cosavirus. There was no significant difference in detection rate (p 0.59) or mean virus load (p 0.43) of Cosa-CHN between the cases and controls. Statistical analysis revealed no association between Cosa-CHN and AGE (p 0.76), and the virus did not exacerbate clinical symptoms. CONCLUSIONS: A low prevalence of HCosV was detected, but a novel Cosavirus species was found in children with and without gastroenteritis in this study. The evidence did not support a causative role for the novel virus in paediatric AGE.

A novel type of cosavirus from children with nonpolio acute flaccid paralysis.

Human cosavirus (HCoSV) is a genus recently identified in the family Picornaviridae, which contains important pathogens to human health. Here, a novel type of HCoSV strain, cosavirus-zj-1 (GenBank no. KX545380), was identified in the fecal sample of a child with nonpolio acute flaccid paralysis (AFP) in China. Phylogenetic and sequence analyses suggested that this virus strain belonged to a new genotype in HCoSV B species. Our data show that surveillance of HCoSV is necessary for detecting viral agents in children with AFP, despite being the low detection rate.

Cosavirus (family Picornaviridae) in pigs in Thailand and Japan.

Cosavirus is a recently established genus in the family Picornaviridae. The present study investigated the prevalence and genetic diversity of cosaviruses in stool samples collected from piglets and pigs with and without diarrhea in Thailand and Japan. It was observed that the cosavirus-positive rate in Thailand was higher than in Japan (55.4 % vs. 18.9 %). Phylogenetic analysis of a portion of the 5' untranslated region showed that porcine cosavirus strains clustered together in the same branch with members of the species Cosavirus A. These strains showed 97.0 to 100 % nucleotide sequence identity to each other. The virus concentration of cosavirus was very low compared with that detected in a infant with diarrhea. These results demonstrated that cosaviruses were circulating in the swine populations of both countries during the study term; however, it remains unclear whether the virus causes diarrhea in piglets and pigs.

Prevalence of human cosaviruses in Tunisia, North Africa.

A new picornavirus, named human Cosavirus (HCoSV) was isolated recently from stools of children with acute flaccid paralysis (AFP) and healthy children in Pakistan and Afghanistan. Since then, it was also isolated from patients from other countries. Five species are presently identified forming a new genus in the Picornaviridae family. This study reports the detection of HCoSV in stool specimens collected as part of the National Poliovirus surveillance Program in Tunisia, between 2011 and 2012, from patients with AFP and healthy individuals among their contacts. One hundred and ninety four stool samples were investigated by RT-PCR in the 5' non-coding region of the genome. A total of 64 specimens (33%) tested positive for HCoSV. HCoSV positive specimens were found in 36 cases with neurological syndromes and 28 of their healthy contacts. The highest rate of HCoSV infection (62.5%) occurred in children younger than 6 years of age. The sampling date of stool specimens suggested that HCoSV infection occurred regularly over time. Also, the sampling origin of stool specimen showed that HCoSV infection was detected in almost all the governorates of Tunisia from the North to the South of the country. This study is the first report of HCoSV prevalence in the North African region. It contributes to a better knowledge on the geographic distribution and the epidemiology of these viruses.

Detection and molecular characterization of human cosavirus in a pediatric patient with acute gastroenteritis, Japan.

Human cosavirus (HCoSV) is a genus recently identified in the family Picornaviridae, which includes important pathogens in human health. The pathogenicity of HCoSV remains unclear. This study reports that an HCoSV strain, 10928/2012/JPN, was identified and collected from the stool sample of a child with acute gastroenteritis in Japan, with the detection rate of 0.16%. The patient was not co-infected with other common diarrhea-causal viruses, suggesting HCoSV as a causal pathogen in this pediatric patient. Phylogenetic and sequence analyses exhibited that the virus strain was classified as a new genotype in HCoSV A species, and this study is first to detect HCoSV in a clinical specimen collected in Japan. These results showed that surveillance of HCoSV is important for detecting viral agents in children with diarrhea, despite being the low detection rate.

Cytopathic effect of Human cosavirus (HCoSV) on primary cell cultures of human embryonic lung MRC5.

Human cosaviruses (HCoSVs) are newly discovered viruses in Picornaviridae family. Until now, most published studies reported HCoSV detection using molecular techniques and genetic characterization of the virus. Nevertheless, no laboratory has yet reported the replication of these viruses in cultured cell lines. In the present work, the propagation of HCoSV strains isolated from human fecal specimens in MRC5 cell line and their induced cytopathic effects (CPE) was studied. The first sign of virus growth was observed 24-48h after inoculation. The cells rounded up and clumped together rapidly; empty areas became visible and, on the third day of CPE, a remarkable decrease in live cells was observed. This represents the first report on in vitro model of HCoSV replication which opens up opportunities for future investigations of these new viruses.

Occurrence of Human Cosavirus in Wastewater and River Water in Japan.

Human cosavirus was detected using reverse transcription-quantitative polymerase chain reaction in 71 % of raw sewage and 29 % each of secondary-treated sewage and river water samples in the Kofu Basin, Japan. The highest concentration was 2.80 × 10(6) copies/l. Nucleotide sequence analysis revealed multiple genotypes of the virus in wastewater.

Persistent human cosavirus infection in lung transplant recipient, Italy.

Human cosavirus is a novel picornavirus recently identified in feces from children in southern Asia. We report infection with human cosavirus in a patient in the Mediterranean area. The patient was an adult double lung transplant recipient who had chronic diarrhea associated with persistent infection with human cosavirus.