Project description:BACKGROUND:WU polyomavirus (WUPyV), a new member of the genus of Polyomavirus in the family Polyomaviridae, has been found and associated with respiratory tract infections recently. However, its clinical role and pathogenicity has not been known. OBJECTIVES:To confirm that WU polyomavirus has been found in Chinese children. STUDY DESIGN:WU polyomavirus was detected and identified using PCR methods. A total of 278 specimens of nasopharyngeal aspirate were collected, and then PCR products were sequenced directly. RESULTS:One of 278 nasopharyngeal aspirates was positive for WUPyV in one child, and the positive rate was 0.4%. The results showed that the sequences of genome, LTAg and VP2 gene was identical to the reference sequences of WU polyomavirus prototype strains. CONCLUSIONS:We confirmed that WU polyomavirus had been found and identified in the respiratory secretions in China.
Project description:OBJECTIVE:To investigate the relationship of KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) with acute respiratory infection in children in Tianjin, China. METHODS:A total of 3?730 nasopharyngeal secretions were collected from hospitalized children with acute respiratory infection in Tianjin Children's Hospital from January 2011 to December 2013. Viral nucleic acid was extracted, and virus infection (KIPyV and WUPyV) was determined by PCR. Some KIPyV-positive and WUPyV-positive PCR products were subjected to sequencing. Sequencing results were aligned with the known gene sequences of KIPyV and WUPyV to construct a phylogenetic tree. Amplified VP1 fragments of KIPyV were inserted into the cloning vector (PUCm-T) transformed into E.?coli competent cells. Positive clones were identified by PCR and sequencing. The nucleotide sequences were submitted to GenBank. In addition, another seven common respiratory viruses in all samples were detected by direct immunofluorescence assay. RESULTS:In the 3?730 specimens, the KIPyV-positive rate was 12.14% (453/3?730) and the WUPyV-positive rate was 1.69% (63/3?730). The mean infection rate of KIPyV was significantly higher in June and July, while the mean infection rate of WUPyV peaked in February and March. Most of the KIPyV-positive or WUPyV-positive children were <3 years. The co-infections with KIPyV, WUPyV, and other respiratory viruses were observed in the children. The co-infection rate was 2.31% (86/3?730) and there were nine cases of co-infections with WUPyV and KIPyV. Thirty-five KIPyV-positive and twelve WUPyV-positive PCR products were sequenced and the alignment analysis showed that they had high homology with the known sequences (94%-100% vs 95%-100%). The VP1 gene sequences obtained from two KIPyV strains in this study were recorded in GenBank with the accession numbers of KY465925 and KY465926. CONCLUSIONS:For some children with acute respiratory infection in Tianjin, China, the acute respiratory infection may be associated with KIPyV and WUPyV infections. KIPyV infection is common in summer, and WUPyV infection in spring. The epidemic strains in Tianjin have a high homology with those in other regions.
Project description:WU polyomavirus was detected in nasopharyngeal aspirates in 2 (2.5%) of 79 children with respiratory infections (both infected with respiratory syncytial virus) and in 5 (6.4%) of 78 asymptomatic children during the same winter season in Canada. The strains were closely related to Australian and American viruses based on analysis of large T antigen (TAg) and VP2 genes. The pathogenic role of WU virus is still uncertain.
Project description:In South Korea, WU polyomavirus (WUPyV) was detected in 34 (7%) of 486 children with acute lower respiratory tract infections, 3 (4.2%) of 72 asymptomatic children, and as coinfection with other respiratory viruses in 23 (67.6%) children. Although WUPyV was frequently detected, its clinical role has not been distinguished from that of coinfecting viruses.
Project description:A novel polyomavirus (WU virus) has been identified in pediatric patients with acute respiratory tract infections (ARI), but its role as a respiratory pathogen has not yet been demonstrated. To investigate if WU virus is related to acute respiratory infections in infants and children in Beijing, specimens collected from 674 pediatric patients with ARI from April 2007 to May 2008 and from 202 children without ARI were used for this investigation. Common respiratory viruses were tested by virus isolation and/or antigen detection by indirect immunofluorescent assay followed by RT-PCR or PCR for other viruses associated with respiratory infections in specimens collected from patients with ARI before WU virus DNA was detected. WU virus DNA was detected by initial screening and secondary confirmation PCR for all specimens. The region encoding the VP2 gene of the virus was amplified from 17 WU-virus-positive clinical specimens, and sequence analysis was performed. Thirty-eight of 674 (5.6%) specimens from patients with ARI and 3 of 202 (1.5%) specimens from children without ARI yielded PCR products with the predicted molecular weight, using either screening or confirmation primer sets, indicating that these specimens were WU virus positive. However, more than 60% of the 38 WU-virus-positive specimens from patients with ARI were also positive for one or more respiratory viruses. The nucleotide and deduced amino acid sequences of the region encoding the VP2 gene from 17 Beijing WU viruses shared high homology (>98.5%) with sequences from GenBank and among themselves. The data indicated that WU virus in Beijing occurred 3.7 times more frequently in pediatric patients with ARI than in those without ARI (p < 0.05).
Project description:BACKGROUND:WU polyomavirus (WUPyV) is a relatively new virus associated with respiratory infections. However, its role is unclear in children with severe respiratory failure. OBJECTIVES:We aimed to evaluate the characteristics of severe respiratory failure associated with WUPyV infection in children. STUDY DESIGN:We retrospectively reviewed cases of respiratory tract infection at a tertiary children's hospital in Japan and performed real-time polymerase chain reaction (PCR) for WUPyV using residual extracted nucleic acid samples taken from respiratory tract samples of pediatric patients primarily with respiratory failure. We investigated the clinical characteristics of patients positive for WUPyV and assessed samples positive for WUPyV for other respiratory pathogens using multiplex PCR. RESULTS:WUPyV was detected in 14 of 318 specimens of respiratory tract infections. The median age was 34 months and males were predominant (n?=?11, 64%). An underlying disease was found in 11 (79%) patients including five preterm and three immunocompromised patients. The most common clinical diagnosis was pneumonia (n?=?13, 93%). The majority of the samples were endotracheal tube aspirates (n?=?11, 79%). Other viruses were co-detected in nine (64%) patients, while WUPyV was the only pathogen detected in five patients with a history of admission to the neonatal intensive care unit. These five patients presented with fever and cough, and perihilar infiltrates were detected on chest radiograph in several days. CONCLUSIONS:WUPyV was detected in children with severe respiratory failure independently or concurrently with other pathogens. WUPyV can be a pathogen for children with a history of preterm birth or an underlying disease.
Project description:WU polyomavirus (WUPyV) is a novel member of the family Polyomaviridae recently detected in respiratory tract specimens. So far, it has not been proven whether WUPyV is a real causative agent for respiratory diseases. In this study, we described two patients with fatal infection who had WUPyV detected in their nasopharyngeal swabs. Furthermore, we conducted a multicentre study in six hospitals from different districts of China. WUPyV was detected by real-time polymerase chain reaction assays, and the clinical and molecular epidemiological characteristics of WUPyV strains among hospitalized children with acute lower respiratory tract infections all around China from 2017 to 2019 were analysed. Two complete WUPyV genome sequences were assembled from fatal patients' airway specimens. Phylogenetic tree analysis revealed that they were most closely related to strains derived from Fujian and Chongqing, China, in 2008 and 2013, respectively. In 2017-2019, a total of 1,812 samples from children with acute lower respiratory tract infections were detected for WUPyV, of which 11 (0.6%) were positive. Children aged ≤5 were more susceptible to WUPyV infection. A total of 81.8% of WUPyV-positive patients were coinfected with other viruses, of which rhinovirus enjoyed the highest frequency. The main clinical symptoms of infected patients include fever, coughing and sputum expectoration. Most patients were diagnosed with pneumonia, followed by bronchial surgery. Three patients manifested severe infection, and all patients improved and were discharged. Our results show that WUPyV persistently circulates in China. Further investigations on the clinical role and pathogenicity of WUPyV are necessary.
Project description:To determine if human bocavirus 2 (HBoV2) has a circular genome similar to the head-to-tail sequence of HBoV1 and the episomal form of HBoV3, 15 HBoV2 positive samples identified from 553 stool specimens from children with acute diarrhea were tested for a head-to-tail sequence using TaqMan-based real-time PCR. A circular genome with a head-to-tail sequence was identified in one (BJQ435) out of 15 samples tested by nested PCR. The complete circular genome of HBoV2-C1 (BJQ435) was 5307 nt in length and was flanked with a 520 nt-long terminal non-coding region (NCR). The secondary structure of HBoV2 -C1 had some differences compared to HBoV3-E1 (JN086998). Our study indicates that the HBoV genome exists in the form of a head-to-tail monomer and provides more information for understanding the HBoV replication mechanism.