Remarkable increase in the detection and molecular characterization of adenovirus F41 in children with acute gastroenteritis in Japan, 2017-2023.

Human adenovirus (HAdV) is one of the causative viruses of acute gastroenteritis (AGE) in children worldwide. Species F is known to be enteric adenovirus (genotypes 40 and 41) detected in stool samples. In Japan, we conducted an epidemiological study and molecular characterization of HAdV before and after the COVID-19 pandemic from 2017 to 2023. Among 821 patients, HAdV was detected in 118 AGE cases (14.4%). During a period of 6 years, the HAdV detection rates for each year were relatively low at 3.7% and 0%, in 2017-2018, and 2020-2021, respectively. However, the detection rate increased to remarkably high rates, ranging from 13.3% to 27.3% in the other 4-year periods. Of these HAdV-positive strains, 83.1% were F41 genotypes and 16.9% were other genotypes (A31, B3, C1, C2/C6, and C5). Phylogenetic analyses of the nucleotide and deduced amino acid sequences of the full-length hexon gene demonstrated that HAdV-F41 strains were comprised of three clades, and each clade was distributed across the study period from 2017 to 2023. Analysis of deduced amino acid sequences of the hexon gene of the representative HAdV-F41 strains from each clade revealed numerous amino acid substitutions across hypervariable regions (HVRs) from HVR-1 to HVR-7, two insertions in HVR-1 and HVR-7, and two deletions in HVR-1 and HVR-2 of the hexon gene compared to those of the prototype strain, particularly, those of clade 3 HAdV-F41 strains. The findings suggested that the HAdV-F41 of each clade was stable, conserved, and co-circulated for over two decades in Japan.

Adenovirus infection in adult patients undergoing allogeneic hematopoietic stem cell transplant: Incidence, clinical management, and outcome.

BACKGROUND: Adenovirus infection (ADVi) is an emergent complication in adult patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with poor outcome. Available data on risk factors and optimal management of ADVi in adult allo-HSCT recipients are limited, and recommendations on monitoring and pre-emptive therapy are mainly based on pediatric data. METHODS: In this single-center, retrospective study, we reported all cases of positive ADV-DNA from adult patients undergoing allo-HSCT in the period 2014-2019. The study aimed to describe the incidence of ADVi at day +180 post-transplant. Secondly to describe timing, clinical presentation, risk factors, and outcome of ADVi and to analyze the application of a screening strategy in our cohort. RESULTS: In 445 allo-HSCT recipients, the day +180 incidence was: 9% (39/445) for ADVi, 5% (24/445) for ADV viremia (ADVv), and 3% (15/445) for localized ADVi. The median time to ADVi was 65 (IQR 19; 94) days after HSCT. ADVv-related mortality was 13% (3/24), all cases occurring with blood max-ADV-DNA > 10^3 cp/mL. Independent risk factors for ADVi were diagnosis of lymphoproliferative disease (p = .011) and acute graft-versus-host-disease (p = .021). CONCLUSIONS: In our cohort, ADVi and ADVv were more frequent than previously reported. ADVv with max-ADV-DNA > 10^3 cp/mL was associated with ADV-related mortality, thus careful monitoring and early initiation of treatment are advisable.

Epidemiological investigation of fowl adenovirus (FAdV) infections in ducks and geese in Shandong Province, China.

RESEARCH HIGHLIGHTS: Samples of suspected FAdV-infected waterfowl from farms in Shandong Province were collected from 2019 to 2022.Single infections with FAdV were less frequent than mixed infections.477 out of 792 samples (60.23%) tested positive for FAdV nucleic acids.Detection rate of FAdV was 65.47% in fattening duck farms, 55.73% in breeder duck farms and 54.55% in fattening geese farms.

Molecular characterisation of fowl adenovirus associated with hydropericardium hepatitis syndrome in broiler and layer breeders in Azerbaijan.

BACKGROUND: Fowl adenovirus-4 is a causative agent of hydropericardium hepatitis syndrome (HHS) in chickens and has been frequently reported from many countries. Fowl adenoviruses cause severe disease and mortality in broiler and layer breeders in Azerbaijan. Therefore, in this study, pathological lesions and the dissemination of fowl adenovirus-4 into the visceral organs of infected birds were investigated as well as molecular characterisation of detected strains. For this, liver, heart and spleen from 20 necropsied chickens originated from a broiler breeder flock and a layer breeder flock were embeded on the FTA cards and the samples were analysed for adenovirus-DNA by PCR and sequencing. RESULTS: The findings of necropsy in both broiler and layer breeder chickens were similar, and the liver was severely effected showing hepatitis, and the heart with hydropericardium lesions. The kidneys were swollen with haemorrhages and small white foci on the surface of the spleens were noted. Intestinal congestion and ecchymotic hemorrhages were also observed in some birds. Fowl adenovirus-4-DNA was detected by PCR in all collected organs of 20 birds. The sequence analysis revealed that fowl adenovirus-4 present in Azerbaijan and close similarity of the hexon genes of the adenoviruses existing in the Middle East, North America, far east and Indian subcontinent were determined by phylogenetic analysis. However, sequence diversity was detected from the adenovirus strains circulating in Europe, North and South America. CONCLUSIONS: This study indicates the impact of fowl adenovirus-4 on the poultry health and production, and improved disease control and prevention strategies are necessary to reduce the HHS disease in chickens in Azerbaijan.

Recent Increase in Incidence of Severe Acute Hepatitis of Unknown Etiology in Children is Associated with Infection with Adenovirus and Other Nonhepatotropic Viruses.

OBJECTIVE: To evaluate whether the nature and severity of non-A-E severe acute hepatitis in children noted by the World Health Organization from late 2021 through early 2022 was indeed increased in 2021-2022 compared with prior years. STUDY DESIGN: We performed a single-center, retrospective study to track the etiology and outcomes of children with non-A-E severe acute hepatitis in 2021-2022 compared with the prior 3-year periods (2018-2019, 2019-2020, and 2020-2021). We queried electronic medical records of children ≤16 years of age with alanine or aspartate aminotransferase levels of >500 IU. Data were analyzed for the periods of October 1, 2021, to May 1, 2022, and compared with the same time periods in 2018-2021. RESULTS: Of 107 children meeting entry criteria, 82 cases occurred from October to May of 2018-2022. The average annual case number was 16.3 in 2018-2021 compared with a 2-fold increase (to 33) in 2021-2022 (P = .0054). Analyses of etiologies showed that this increase was associated with a higher number of children who tested positive for viruses (n = 16) when compared with the average of 3.7 for 2018-2021 (P = .018). Adenovirus (26.1%) and severe acute respiratory syndrome coronavirus-2 (10.3%) were the most frequently detected viruses in 2021-2022. Despite evidence of acute liver failure in 37.8% of children in the entire cohort and in 47% of those with viral infection, the overall survival rate was high at 91.4% and 88.9%, respectively. CONCLUSIONS: The number of children with severe acute hepatitis in our center increased from 2021 to May 2022, with a greater frequency of cases associated with adenovirus, yet transplant-free survival remains high.

Genome sequencing reveals molecular epidemiological characteristics and new recombinations of adenovirus in Beijing, China, 2014-2019.

To investigate the molecular epidemiological characteristics and genetic variations of human adenovirus (HAdV) in acute respiratory tract infections in Beijing. Whole-genome sequencing and phylogenetic analyses were performed for 83 strains of HAdV with different types in Beijing from 2014 to 2019. The clinical characteristics of HAdV infection were analyzed statistically. HAdV-B was divided into four genotypes, including B3 (n = 11), B7 (n = 13), B14 (n = 4), and B55 (n = 2). HAdV-C was divided into three genotypes, including C1 (n = 14), C2 (n = 13), and C5 (n = 10). In HAdV-C, nine recombinant adenovirus strains were identified in type 1, and seven recombinant strains were found in type 2. In type 1, we found three newly emerged intraspecific recombinant strains (A47, A48, and A52) collected in 2017, 2018, and 2019, respectively. In addition, the previously reported recombinant strains of HAdV-C1 showed more severe disease than other strains of HAdV-C, causing severe community-acquired pneumonia in both the elderly and children. Continuous population-wide molecular epidemiological surveillance of HAdV is essential for the prevention and control of respiratory infectious diseases.

A multicentre study on the incidence of respiratory viruses in children with community-acquired pneumonia requiring hospitalization in the setting of the zero-COVID policy in China.

BACKGROUND: Stringent nonpharmaceutical interventions (NPIs) have been implemented worldwide to combat the COVID-19 pandemic, and the circulation and seasonality of common respiratory viruses have subsequently changed. There have been few multicentre studies or comparisons of the prevalence of respiratory viruses accounting for community-acquired pneumonia (CAP) in hospitalized children between the pre-COVID period and the period after community and school reopening in the setting of the zero-COVID policy. METHODS: We included 1543 children with CAP who required hospitalization from November 1, 2020 to April 30, 2021 (period 1), and 629 children with the same conditions from November 1, 2018, to April 30, 2019 (period 2), in our study. All respiratory samples from these patients were screened for six respiratory viruses (respiratory syncytial virus [RSV], adenovirus [ADV], influenza A virus [Flu A], influenza B virus [Flu B], parainfluenza virus type 1 [PIV1], and parainfluenza virus type 3 [PIV3]) using a multiplex real-time PCR assay. RESULTS AND CONCLUSIONS: The median ages of the enrolled patients at the time of diagnosis were 1.5 years and 1.0 years for period 1 and period 2, respectively. In period 1, viral pathogens were detected in 50.3% (776/1543) of the enrolled patients. The most frequently identified viral pathogen was RSV (35.9%, 554/1543), followed by PIV3 (9.6%, 148/1543), PIV1 (3.6%, 56/1543), ADV (3.4%, 52/1543), Flu A (1.0%, 16/1543), and Flu B (0.8%, 13/1543). The total detection rates of these six viruses in the peak season of CAP were at the pre-COVID level. The prevalence of Flu A decreased dramatically, and circulation activity was low compared to pre-COVID levels, while the incidence of PIV3 increased significantly. There were no significant differences in the detection rates of RSV, ADV, Flu B, and PIV1 between the two periods. Our results showed that respiratory viruses accounted for CAP in hospitalized children at pre-COVID levels as communities and schools reopened within the zero-COVID policy, although the prevalence aetiology spectrum varied.

Molecular phylodynamics of fowl adenovirus serotype 11 and 8b from inclusion body hepatitis outbreaks.

Fowl adenovirus (FAdV) serotypes are involved in a variety of clinical manifestations in poultry and has resulted in substantial economic loss to the poultry farmers. Despite the endemicity of Inclusion body hepatitis (IBH) in South Asian countries, including India, its etiology is not well studied. In western India, the rural poultry flocks obtained from the vaccinated parents were experiencing disease outbreaks with substantial economic losses due to heavy outbreaks and mortality. Therefore, the study was conducted to decipher the molecular epidemiology of the FAdV from field outbreaks in western India. A total of 37 commercial broiler poultry flocks and 29 village poultry flocks of western India were visited during 2019 to 2021. Out of these, 19.14% flocks showed incidence of IBH during the age of 15 to 35 days. The mortality ranged from 3.3 percent to 55.28 percent. The samples were subjected for amplification of partial hexon gene covering loop 1 and loop 2. The results revealed 48.28% positivity by PCR. The sequence analysis identified 14 isolates as species D serotype 11 with 0.97 to 0.99% divergence and two as species E serotype 8b with 0.99% divergence. The FAdV-11 isolates showed amino acid substitutions D195N, T399A, N417S, and N496H. The amino acids I188 and N195 were conserved in FAdV-11. The molecular clock in Bayesian methods was used to determine most common ancestor. The isolates MH379249 and MH379248 were determined the most recent common ancestor for FAdV-11 and FAdV-8b isolates. The analysis suggested evolution of 10 FAdV-11 strains in 2012, and four FAdV-11 strains and two FAdV-8b strains in 2018.

Comparisons of lymphocytes profiles and inflammatory cytokines levels in blood of patients with differed severity of infection by human adenovirus type 7.

BACKGROUND: Human adenovirus (HAdV) infection outbreak causes community-acquired pneumonia. Cellular immune dysfunction and hypercytokinemia play important roles in the pathogenesis of adenovirus respiratory infection. Some soluble factors in peripheral blood can assist in judging the virus-induced disease severity. The expression levels of inflammatory cytokines differ among patients with different disease severity. However, whether and how HAdV-7 infection influences the composition of blood immune cells and serum cytokine levels in patients at different disease stages, as well as the diagnosis values of these parameters, have rarely been intensively studied. We aimed to investigate lymphocytes profiles and cytokines levels in blood of patients at different disease stages upon human adenovirus type 7 (HAdV-7) infections, and explored the diagnosis values of the investigated parameters. METHODS: Patients from two outbreaks of HAdV-7 in military of China were categorized into upper respiratory infection (URI) group, common pneumonia (CP) group and severe pneumonia (SP) group according to disease severity. Peripheral blood samples were subjected to routine laboratory tests, while flow cytometry and ELISA were used to measure the lymphocyte subsets and cytokines in blood, respectively. The receiver operating characteristic (ROC) curves were performed to examine the diagnostic of these blood parameters. RESULTS: Signs of imbalanced lymphocytes composition and hypercytokinemia were observed in HAdV-7-infected patients. The percentages of CD3+ T cells and NK cells were significantly decreased along with the aggravation of the disease, particularly for NK cells and CD4+ T cells. The neutrophil to lymphocyte ratio (NLR) increased significantly in patients with more severe disease. In addition, the levels of serum CXCL10, IL-2 and TNF-α were positively correlated with disease severity, while reduced levels of IFN-γ and IL-10 were found in SP patients. Furthermore, analysis of ROC showed that multiple parameters including the percentage of blood CD3+ cells and serum CXCL10 level could predict the progression of HAdV-7 infection. CONCLUSION: Imbalance of immune state with hypercytokinemia occurred during HAdV-7 infection. The percentages of blood immune cells such as CD3+ T cells and the levels of serum cytokines such as CXCL10 showed potential diagnosis values in HAdV-7 infection.

Association of adenovirus 36 infection and obesity; An updated meta-analysis of community-based studies.

As a health problem, obesity has several risk factors; it has been suggested that human adenovirus type 36 (HAdV-36) infections may possibly be associated with obesity. This updated meta-analysis was designed and conducted with an emphasis on articles published from 2015 to 2020. The PubMed, Web of Science, and Scopus databases were searched up to 1 December 2020. Overall, pooled prevalence and odds ratio of antibodies against HAdV-36 in people with obesity and controls was assessed among different ages. Case-control and cohort studies were included in the analysis. The overall prevalence of HAdV-36 infection in obese population was 31% (CI: 0.24%-0.38%) which was 32% in cases and 27% in controls, respectively; a significant association was found between the cases and the controls (OR, 1.84; 95% CI, 1.39-2.43), especially in children younger than 18 years of age (OR, 2.44; 95% CI, 1.85-3.22). A significant association between adenovirus infection and obesity was found, especially in adolescents.

Adenovirus infection in allogeneic hematopoietic cell transplantation.

Adenovirus (AdV) infection occurs in 0-20% of patients in the first 3-4 months after allogeneic hematopoietic cell transplantation (HCT), being higher in pediatric than in adult patients. About 50% of AdV infections involve the blood, which in turn, correlates with an increased risk developing AdV diseases, end-organ damage, and 6-month overall mortality. The main risk factors for AdV infection are T-cell depletion of the graft by ex vivo selection procedures or in vivo use of alemtuzumab or antithymocyte serum, development of graft versus host disease (GVHD) grade III-IV, donor type (haploidentical or human leucocyte antigen mismatched related donor > cord blood> unrelated matched donor) and severe lymphopenia (<0.2 × 109 /L). The prevention of AdV disease relies on early diagnosis of increasing viral replication in blood or stool and the pre-emptive start of cidofovir as viral load exceeds the threshold of ≥102-3 copies/mL in blood and/or 106 copies/g stool in the stool. Cidofovir (CDV), a cytosine monophosphate nucleotide analog, is currently the only antiviral recommended for AdV infection despite limited efficacy and moderate risk of nephrotoxicity. Brincidofovir, a lipid derivative of CDV with more favorable pharmacokinetics properties and superior efficacy, is not available and currently is being investigated for other viral infections. The enhancement of virus-specific T-cell immunity in the first few months post-HCT by the administration of donor-derived or third-party-donor-derived virus-specific T-cells represents an innovative and promising modality of intervention and data of efficacy and safety of the ongoing prospective randomized studies are eagerly awaited.

Molecular epidemiology analysis of fowl adenovirus detected from apparently healthy birds in eastern China.

BACKGROUND: Fowl adenovirus is of major concern to the poultry industry worldwidely. In order to monitor the prevalent status of Fowl adenovirus in China, a total of 1920 clinical samples from apparently healthy birds in the 25 sites of poultry flocks, Slaughterhouse and living bird markets from 8 provinces in eastern China were collected and detected by PCR, sequencing, and phylogenetic analysis. RESULTS: The epidemiological survey showed that Fowl adenoviruses were detected in living bird markets, and circulating in a variety of fowl species, including chickens, ducks, goose and pigeons. Among the 1920 clinical samples, 166 samples (8.65%) were positive in the fowl adenovirus PCR detection. In this study, totally all the 12 serotypes (serotypes of 1, 2, 3, 4, 5, 6, 7, 8A, 8B, 9, 10 and 11) fowl adenoviruses were detected, the most prevalent serotype was serotype 1. Phylogenetic analysis indicated that 166 FAdVs of 12 serotypes were divided into 5 fowl adenovirus species (Fowl aviadenovirus A, B, C, D, E). CONCLUSIONS: In the epidemiological survey, 8.65% of the clinical samples from apparently healthy birds were positive in the fowl adenovirus PCR detection. Totally all the 12 serotypes fowl adenoviruses were detected in a variety of fowl species, which provided abundant resources for the research of fowl adenoviruses in China. The newly prevalent FAdV serotypes provides valuable information for the development of an effective control strategy for FAdV infections in fowls.

Factors Associated with Severe Adenovirus Pneumonia in Children: A Retrospective Study from Guangzhou, China (2017-2019).

BACKGROUND Adenovirus infections are prevalent in children, typically presenting with mild or asymptomatic symptoms. However, some children develop severe pneumonia necessitating hospitalization. This retrospective study aimed to identify risk factors associated with severe adenovirus pneumonia in children. MATERIAL AND METHODS We screened consecutive children admitted for community-acquired pneumonia at the Emergency Department of Guangzhou Women's and Children's Medical Center between 2017 and 2019. Adenovirus infection was confirmed through rapid respiratory virus assay, RT-PCR assay from respiratory secretions, or serum IgM antibodies. According to Chinese guidelines, patients with pneumonia were classified into severe and mild groups. We assessed risk factors for severe adenovirus pneumonia by comparing clinical features and laboratory indicators, then included differing factors between the 2 groups in a logistic regression analysis. Data analysis was performed using SPSS 26.0 software. RESULTS Our study included 173 children diagnosed with adenovirus pneumonia (117 severe, 56 mild). The median age was 40 months, with 64 male patients. Univariate analysis and binary logistic regression analysis revealed that pleural effusion (13.449 [1.226-147.510], p=0.033), electrolyte disturbances (15.149 [2.724-84.246], p=0.002), oxygen therapy (258.219 [20.684-3223.548], p<0.001), bronchoscopy (26.781 [6.088-117.805], p<0.001), and steroid administration (6.584 [1.497-28.953], p=0.013) were associated with the severity of adenovirus pneumonia. CONCLUSIONS This single-center retrospective study identified pleural effusion, the need for bronchoscopy, oxygen therapy, and steroid treatment, along with impaired serum electrolytes, as factors associated with severe adenovirus pneumonia in children.

Rotavirus and adenovirus prevalence in patients with acute viral gastroenteritis in Denizli, Turkey, 2017-2021.

This study aims to determine retrospectively the prevalence of rotavirus and enteric adenovirus in patients with gastroenteritis symptoms and the distribution of pathogens by gender, age, seasons, and years. The stool samples sent to Pamukkale University Healthcare Research and Practice Hospital's Medical Microbiology laboratory between January 2017 and December 2021 were evaluated for rotavirus/adenovirus antigen positivity. Rotavirus and adenovirus antigens were studied with the Rotavirus-Adenovirus Combo Rapid Cassette Test (Acro Biotech) kit. Rotavirus was detected in 683 (8.2%) of the 8315 stool samples evaluated, and 180 (2.2%) samples were positive for adenovirus. Coinfection was detected in 21 (0.25%) samples. Rotavirus was found at the highest rate in 2019 (p = 0.001). The adenovirus was detected in 2020 at a lower rate than in other years (p = 0.0001). The rotavirus was observed at a higher rate in 0-<3, 3-<6, and 6-<13 age groups and adenovirus was detected at a higher rate in 3-<6 and 6-<13 age groups compared to other age groups (p = 0.001, p = 0.003, respectively). The highest rate of incidence of the rotavirus was found in spring and adenovirus in winter. In the etiology of gastroenteritis, especially in children, adenovirus and rotavirus should not be ignored in winter and spring. The prevalence of rotavirus was observed to have decreased in 2020 and onwards, and the prevalence of adenovirus decreased in 2020.

Seroprevalence and molecular characterization of human respiratory syncytial virus and human adenovirus among children in Ado-Ekiti, Nigeria.

In children, the respiratory syncytial virus and adenovirus majorly cause acute respiratory infections. The study evaluated the seroprevalence and conducted the molecular characterization of human respiratory syncytial virus (HRSV) and human adenovirus (HAdV) among children. Venous blood, nasopharyngeal, and oropharyngeal swabs were collected from children presenting with acute respiratory infections in a tertiary health facility in Ado-Ekiti, Nigeria. A serological investigation was carried out on the sera samples for the detection of anti-HRSV immunoglobulin M (IgM), anti-HRSV IgG, anti-HAdV IgM, and anti-HAdV IgG using ELISA (enzyme-linked immunosorbent assay) kits. The amplification and sequencing of HRSV and HAdV were carried out using specific primer pairs that targeted the glycoprotein (G) gene of HRSV and the hexon gene of HAdV, respectively. The seroprevalence of HRSV IgG and IgM was 73% and 7.5%, respectively, while the seroprevalence of HAdV IgG and IgM was 98.5% and 8.5%, respectively. The age of enrolled children, presence of fever, and cough were associated (p < 0.05) with the infection. HRSV subtype B (HRSV-B) (13.3%), and species of HAdV (Mastadenovirus B and C) (11.7%) were detected among the studied population. There was no viral coinfection with both HRSV and HAdV. In infancy and early childhood, HRSV-B, HAdV species B and C are common etiologic agents of respiratory infections as reported in this study. Further studies on molecular characterization of respiratory tract viruses including circulating respiratory syncytial virus and adenovirus are hereby advocated.

Infection with adenovirus, rotavirus, and coinfection among hospitalized children with gastroenteritis in an Egyptian university hospital.

Acute gastroenteritis is the main cause of mortality and morbidity in children worldwide. Studies stated that rotavirus and human adenovirus (HAdV) are common causes of nonbacterial gastroenteritis in children aged 0-5 years. The aim of this study was to determine the prevalence and the distribution of rotavirus, HAdV, and coinfections among hospitalized children with gastroenteritis below 7 years old and determine the prevalence of enteric HAdV among all HAdV gastroenteritis. The study was conducted on 150 children below 7 years old. Antigen detection for rotavirus and HAdV by ELISA and determination of enteric HAdV (serotype 40 and 41) by nested PCR and restriction endonucleases study were performed. Detection of rotavirus and HAdV antigens in 150 stool specimens from patients with gastroenteritis were 58% (87), 6.7% (10), and 8% (12) positive for rotavirus, HAdV, and coinfection, respectively. Out of 22 HAdV antigen-positive cases, 15 cases were positive by PCR for enteric HAdV, with the prevalence rate of enteric HAdV gastroenteritis among all HAdV gastroenteritis cases of 68%, a serotyping study by PCR detected serotype 40 in 46.7% of cases (7/15) and serotype 41 in 53.3% of cases (8/15) with no statistically significant difference between them. The study confirmed that rotavirus and HAdV are prevalent etiological agents of diarrhea in children below the school-age group, highlighting the necessity of the rotavirus vaccine in addition to the obligatory schedule of vaccines in Egypt. Also, it determined that the enteric HAdV gastroenteritis prevalence rate was 68% among all HAdV gastroenteritis.

Nonpharmaceutical interventions against the COVID-19 pandemic significantly decreased the spread of enterovirus in children.

Precise prevention and control measures have been adopted to impede the transmission of coronavirus disease 2019 (COVID-19) in China. This study was performed to investigate the effect of protective measures on gastrointestinal infection in children during the COVID-19 pandemic. The data on the rotavirus and adenovirus antigen tests were collected in outpatient children due to gastroenteritis from January 1, 2019 to December 31, 2020, at the Children's Hospital of Zhejiang University School of Medicine. According to age and month distribution, the positive number and rate of rotavirus and adenovirus in 2020 were compared with 2019. A 3.8-fold and 4-fold reduction in the number of rotavirus- and adenovirus-positive patients in 2020 were found, respectively. The overall positive rate of rotavirus and adenovirus infection was drastically decreased in 2020 (rotavirus 2020: 18.18% vs. 2019: 9.75%, p < 0.001; adenovirus 2020: 3.13% vs. 2019: 1.58%, p < 0.001). The proportions of rotavirus and adenovirus in all age groups in 2020 decreased compared with those in 2019. The highest frequency of rotavirus infection occurred among children aged 1-3 years both in 2019 and 2020 (2019: 27.95% vs. 2020: 17.19%, p < 0.001), while adenovirus infection was detected in children aged 3-5 years, which had the highest percent positivity (2019: 8.19% vs. 2020: 4.46%; p < 0.001). An obvious peak prevalence of rotavirus incidence was found during December-April, and the percent positivity of rotavirus significantly decreased in 2020 (December 2019: 24.26% vs. 2020: 8.44%, p < 0.001; January 2019: 40.67% vs. 2020: 38.18%, p < 0.05; February 2019: 40.73% vs. 2020: 15.04%, p < 0.001; March 2019: 31.47% vs. 2020: 7.88%, p < 0.001; April 2019: 15.52% vs. 2020: 4.78%, p < 0.001). The positive rate of adenovirus distributed throughout 2019 was 1.91%-4.86%, while the percent positivity during 2020 in the same period was much lower (0.00%-3.58%). Our results confirmed that the preventive and control measures adopted during the COVID-19 pandemic and the collateral benefit of these interventions have significantly decreased the transmission of rotavirus or adenovirus.

Gizzard erosions in broiler chickens in Sweden caused by fowl adenovirus serotype 1 (FAdV-1): investigation of outbreaks, including whole-genome sequencing of an isolate.

The present paper describes the investigation of the first outbreaks of adenoviral gizzard erosions (AGE) in Sweden, in five broiler flocks. The investigation included whole viral genome sequencing and investigation of genomic organization and sequence relationships with other adenoviruses. All five flocks had a history of decreased growth and uneven size of birds since 9-10 days of age. Macroscopically, lesions consistent with AGE (detached koilin layers, discolouration, bleeding, erosions) were identified in gizzards in all five flocks. In four flocks histology was performed, and degeneration and inflammation of the koilin layer and gizzard mucosa were identified in all four. In one flock, intranuclear inclusion bodies typical for fowl adenovirus (FAdV) were detected in trapped epithelial cells in the koilin layer. In four flocks in situ hybridization was performed, and cells positive for FAdV serotype 1 (FAdV-1) were demonstrated in the koilin layer and gizzard mucosa. FAdV species A (FAdV-A) was detected in gizzard, liver, caecal tonsils and bursa of Fabricius by polymerase chain reaction (PCR) and sequencing. Ten out of ten examined parent flocks of the affected chickens were seropositive for FAdV, indicating former or on-going infection. However, FAdV was not detected in embryos from seropositive parent flocks and thus vertical transmission was not demonstrated. The entire nucleotide sequence of one sample was determined and found to be 43,856 base pairs (bp) in length. The genome sequence and organization were found to be similar to that of the reference apathogenic avian adenovirus "chicken embryo lethal orphan" (CELO). RESEARCH HIGHLIGHTSAGE in Swedish broilers: necropsy, histopathology, ISH, PCR, whole-genome sequencing.Whole FAdV-genome analysed: 43,856 bp, found to be most similar to CELO (U46933.1).Multiple point mutations, site insertions and deletions identified compared to CELO.Paper adds knowledge about European disease situation and pathogenic FAdV-strains.

Genotyping and pathogenicity of fowl adenovirus isolated from broiler chickens in Egypt.

BACKGROUND: Over the past 10 years, inclusion body hepatitis outbreaks, essentially from commercial broiler flocks, have been detected in different geographic regions highlighting the wide distribution of FAdVs around the world resulting in serious economic losses due to increased mortalities as well as poor performance within poultry farms in Assiut province, Egypt. Thus, this study was achieved to detect fowl adenovirus in broiler chicken flocks in Assiut province, Egypt and to recognize the pathogenicity of the isolated virus. RESULTS: The phylogeny of the L1 loop of the hexon gene exposed that the isolated virus clustered and belonged to the reference strains serotype D FAdV. The isolated virus is closely related to inclusion body hepatitis (IBH) strains causing extensive economic losses. The pathogenicity study of the virus showed typical macroscopic lesions with 6% mortality; furthermore, histopathological inspection exhibited severe hepatitis and degenerative changes after 5d from infection in the immune system.  CONCLUSION: Results in this research support the primary pathogenicity and mortality caused by FADV serotype 2 (IBH) alone without immunosuppressive agents thus robust control measures should be implanted against FAdV to evade the serious economic losses in poultry farms.

Adenovirus can be a serious, life-threatening disease, even in previously healthy children.

AIM: Adenovirus infections are exceedingly common in childhood. However, little is known of the clinical characteristics of children admitted with severe infection to the paediatric intensive care unit (PICU). METHODS: Clinical data on children hospitalised with adenovirus infection between January 2005 and March 2020 were collected. We compared data between children hospitalised in the PICU and those who were not in a 1:2 ratio. RESULTS: During the study period, 69 children with adenovirus infection were admitted to the PICU, representing 5% of all hospitalised children with adenovirus. Thirty-four (49%) were previously healthy children. Mortality occurred in 5 patients, and all had an underlying illness. Cidofovir was used in 21 children, including 11 who were previously healthy. No side effects were attributed to the treatment. During 2005-2014, viral co-infection rates were 42% in the PICU group and 11% in the control group (p = 0.002). However, during 2015-2020, when the viral panel became widespread in our institution, the rates of co-infection were similar in the two groups (32% and 34%, p = 1.0). CONCLUSION: Our findings suggest that adenovirus may present as a serious, life-threatening disease even in previously healthy children.