Severe adenovirus infection outbreak in Colombia: Experience from a tertiary pediatric hospital in 2022. / Brote de adenovirus grave en Colombia: experiencia de un hospital pediátrico de tercer nivel en 2022

Introduction. During the SARS-CoV-2 pandemic, many countries experienced decreased respiratory virus circulation, followed by an out-of-season outbreak. In a pediatric hospital in Colombia, we observed a surge in severe adenovirus infections, leading to concerns about the impact of eased public health restrictions and immune debt in children under five years old. Objective. To describe the clinical characteristics of patients with severe adenovirus infection in a pediatric hospital in Colombia. Materials and methods. We reviewed the data of 227 patients with severe adenovirus infection at the Fundación Hospital Pediátrico La Misericordia. Results. A total of 196 patients were included in this study. The median age was two years, and 62% were male. Adenoviruses were isolated from all patients' samples. Ninetyseven percent were admitted to the pediatric intensive care unit, 94% required respiratory support, and the in-hospital lethality rate was 11%. Conclusion. In 2022, there was an outbreak of severe adenovirus infections, affecting mainly children under five years of age, with higher-than-usual mortality.

Introducción. Durante la pandemia por SARS-CoV-2, muchos países evidenciaron una disminución en la circulación de virus respiratorios, seguida por un brote fuera de la temporada esperada. En un hospital de Colombia, se observó un aumento en los casos de infección grave por adenovirus, lo cual generó preocupación sobre el impacto que tuvo la disminución de los cuidados establecidos durante pandemia y la posible deuda inmunológica en niños menores de cinco años. Objetivo. Describir las características clínicas de los pacientes con infección grave por adenovirus en un hospital pediátrico de Colombia. Materiales y métodos. Se revisaron 227 pacientes con infección grave por adenovirus en la Fundación Hospital Pediátrico La Misericordia, desde el 1° de enero hasta el 31 de diciembre de 2022. Resultados. El estudio incluyó 196 casos. La edad media de los pacientes fue de dos años y el 62 % eran de sexo masculino. Los adenovirus se aislaron a partir de las muestras de todos los pacientes. El 97 % de los pacientes ingresó a la unidad de cuidados intensivos, el 94 % requirió soporte ventilatorio y la tasa de mortalidad fue del 11 %. Conclusiones. En el 2022 hubo un brote de adenovirus que afectó principalmente a los niños menores de cinco años, con una mortalidad mayor a lo reportado con anterioridad en Colombia.

Changes in frequency of benign convulsions with mild gastroenteritis and their viral causes before and during the COVID-19 pandemic: a single-center study.

BACKGROUND: Benign convulsions with mild gastroenteritis (CwG) are prevalent in young children during the winter. Early in the coronavirus disease 2019 (COVID-19) pandemic, viral gastroenteritis occurrence decreased and seasonal variation was lost, which can change CwG. PURPOSE: Here we investigated changes in frequency, seasonal variation, and causative viruses of CwG during the COVID-19 pandemic. METHODS: We screened 1134 patients (3-36 months) with "other and unspecified convulsions" treated at Chonnam National University Hospital between March 2017 and February 2023; of them, we enrolled 41 (3.6%) with CwG. We compared their medical records from period I (March 2017 to February 2020) to those from period II (March 2020 to February 2023). Publicly available viral gastroenteritis surveillance data from the Korea Disease Control and Prevention Agency (KDCA) were reviewed as reference. RESULTS: Of the 41 patients with CwG, 18 (2.9% of 613) were affected in period I versus 23 (4.4% of 512) in period II (P=0.184). In period I, CwG mainly occurred in winter and spring (55.6% and 22.2%, respectively). In period II, there were fewer CwG cases (39.1%) in winter and more cases in summer and autumn (26.1% and 17.4%, respectively): the cases of norovirus genogroup II (GII)-associated CwG increased significantly in the summer (38.5% vs. 0%, P= 0.046). Norovirus GII was the most common virus (56.1% of isolates). Enteric adenovirus was the second most common (19.5%), with one case in period I and 7 cases in period II (P=0.059). The clinical characteristics of enteric adenovirus-associated CwG were similar to those of norovirus. Seasonal changes in and viral causes of CwG were consistent with those observed in the KDCA stool surveillance data. CONCLUSION: During the COVID-19 pandemic, CwG frequency did not change, seasonal variation was unapparent, and enteric adenovirus-associated CwG frequency increased.

Acute Adenoviral Infection Elicits an Arrhythmogenic Substrate Prior to Myocarditis.

BACKGROUND: Viral cardiac infection represents a significant clinical challenge encompassing several etiological agents, disease stages, complex presentation, and a resulting lack of mechanistic understanding. Myocarditis is a major cause of sudden cardiac death in young adults, where current knowledge in the field is dominated by later disease phases and pathological immune responses. However, little is known regarding how infection can acutely induce an arrhythmogenic substrate before significant immune responses. Adenovirus is a leading cause of myocarditis, but due to species specificity, models of infection are lacking, and it is not understood how adenoviral infection may underlie sudden cardiac arrest. Mouse adenovirus type-3 was previously reported as cardiotropic, yet it has not been utilized to understand the mechanisms of cardiac infection and pathology. METHODS: We have developed mouse adenovirus type-3 infection as a model to investigate acute cardiac infection and molecular alterations to the infected heart before an appreciable immune response or gross cardiomyopathy. RESULTS: Optical mapping of infected hearts exposes decreases in conduction velocity concomitant with increased Cx43Ser368 phosphorylation, a residue known to regulate gap junction function. Hearts from animals harboring a phospho-null mutation at Cx43Ser368 are protected against mouse adenovirus type-3-induced conduction velocity slowing. Additional to gap junction alterations, patch clamping of mouse adenovirus type-3-infected adult mouse ventricular cardiomyocytes reveals prolonged action potential duration as a result of decreased IK1 and IKs current density. Turning to human systems, we find human adenovirus type-5 increases phosphorylation of Cx43Ser368 and disrupts synchrony in human induced pluripotent stem cell-derived cardiomyocytes, indicating common mechanisms with our mouse whole heart and adult cardiomyocyte data. CONCLUSIONS: Together, these findings demonstrate that adenoviral infection creates an arrhythmogenic substrate through direct targeting of gap junction and ion channel function in the heart. Such alterations are known to precipitate arrhythmias and likely contribute to sudden cardiac death in acutely infected patients.

Detection of skunk adenovirus-1 in domestic ferrets (Mustela putorius).

We describe gross pathology, histopathology, ultrastructure, and molecular characterization of skunk adenovirus 1 (SkAdV-1) in 3 ferrets (Mustela putorius) submitted to the Infectious Diseases Laboratory, Zoo and Exotic Animal Pathology Service at the University of Georgia. Case 1 came from a cohort with a 6-week history of multiple ferrets with respiratory disease and mortality. Cases 2 and 3 were submitted 19 days later; they died 3 days after arrival at the vendor's facility. Histopathological evaluation found evidence of suppurative bronchopneumonia, with intralesional gram-positive cocci in case 1. The others had evidence of subacute multifocal histiocytic and lymphoplasmacytic interstitial pneumonia. Viral isolation, polymerase chain reaction (PCR), and DNA sequencing identified SkAdV-1 in lung tissue. In situ hybridization confirmed adenovirus within the lung lesion, and adenovirus particles were visible under an electron microscope. This is the seventh species in which SkAdV-1 has been identified. Cross-species transmission events have important implications for wildlife management and multispecies facilities.

Characterisation of a novel aviadenovirus associated with disease in tawny frogmouths (Podargus strigoides).

Aviadenoviruses are widespread in wild birds but rarely cause disease in nature. However, when naïve species are exposed to poultry or aviaries, aviadenoviruses can lead to disease outbreaks. This study characterised a novel aviadenovirus infection in a native Australian bird, the tawny frogmouth (Podargus strigoides) during an outbreak investigation. The identified complete genome of aviadenovirus, named tawny frogmouth aviadenovirus A (TwAviAdV-A) was 41,175 bp in length containing 52 putative genes. TwAviAdV-A exhibits the common aviadenovirus genomic organisation but with a notable monophyletic subclade in the phylogeny. The TwAviAdV-A virus was hepatotrophic and the six frogmouths presented to the wildlife hospitals in South Eastern Queensland most commonly exhibited regurgitation (in four frogmouths). Three were died or euthanized, two recovered, and one showed no signs. The detection of TwAviAdV-A in frogmouths coming into care re-emphasizes the need for strict biosecurity protocols in wildlife hospitals and care facilities.

Risk Evaluation and Mitigation Strategies for Potential Outbreaks of Adenovirus Infection: Evidence From the Recent Incidences in West Bengal, India.

Recent outbreaks of highly virulent and pathogenic viruses such as COVID-19, monkeypox, and Nipah virus have prompted global concerns. Another threat has emerged in West Bengal, India, in the form of Human Adenovirus (HAdV), particularly affecting children and immunocompromised individuals. The DNA virus HAdV can cause respiratory, liver, renal, and neurological issues. Politically unstable areas with military and medical camps and refugee communities are at risk because they spread in densely populated areas. Due to its rapid mutation and dissemination, the virus represents a global threat. Although scientists have developed vaccines for specific serotypes of HAdV, their primary application is limited to military contexts. Antiviral and immunotherapy research is continuing, but treatment choices are limited. Public awareness programs and hygiene measures are essential to preventing a global pandemic. Governments should invest in healthcare infrastructure and diagnostics, and researchers should focus on developing vaccines and therapies. The West Bengal outbreak is a clear reminder that governments, healthcare professionals, and researchers must work together to control and prevent HAdV. To effectively comprehend and address this rising viral threat, it is imperative to engage in further research and documentation.

In vivo tracking of adenoviral-transduced iron oxide-labeled bone marrow-derived dendritic cells using magnetic particle imaging.

BACKGROUND: Despite widespread study of dendritic cell (DC)-based cancer immunotherapies, the in vivo postinjection fate of DC remains largely unknown. Due in part to a lack of quantifiable imaging modalities, this is troubling as the amount of DC migration to secondary lymphoid organs correlates with therapeutic efficacy. Magnetic particle imaging (MPI) has emerged as a suitable modality to quantify in vivo migration of superparamagnetic iron oxide (SPIO)-labeled DC. Herein, we describe a popliteal lymph node (pLN)-focused MPI scan to quantify DC in vivo migration accurately and consistently. METHODS: Adenovirus (Ad)-transduced SPIO+ (Ad SPIO+) and SPIO+ C57BL/6 bone marrow-derived DC were generated and assessed for viability and phenotype, then fluorescently labeled and injected into mouse hind footpads (n = 6). Two days later, in vivo DC migration was quantified using whole animal, pLN-focused, and ex vivo pLN MPI scans. RESULTS: No significant differences in viability, phenotype and in vivo pLN migration were noted for Ad SPIO+ and SPIO+ DC. Day 2 pLN-focused MPI quantified DC migration in all instances while whole animal MPI only quantified pLN migration in 75% of cases. Ex vivo MPI and fluorescence microscopy confirmed that pLN MPI signal was due to originally injected Ad SPIO+ and SPIO+ DC. CONCLUSION: We overcame a reported limitation of MPI by using a pLN-focused MPI scan to quantify pLN-migrated Ad SPIO+ and SPIO+ DC in 100% of cases and detected as few as 1000 DC (4.4 ng Fe) in vivo. MPI is a suitable preclinical imaging modality to assess DC-based cancer immunotherapeutic efficacy. RELEVANCE STATEMENT: Tracking the in vivo fate of DC using noninvasive quantifiable magnetic particle imaging can potentially serve as a surrogate marker of therapeutic effectiveness. KEY POINTS: • Adenoviral-transduced and iron oxide-labeled dendritic cells are in vivo migration competent. • Magnetic particle imaging is a suitable modality to quantify in vivo dendritic cell migration. • Magnetic particle imaging focused field of view overcomes dynamic range limitation.

Gastrointestinal tract and viral pathogens.

Viral gastroenteritis is the most common viral illness that affects the gastrointestinal (GI) tract, causing inflammation and irritation of the lining of the stomach and intestines. Common signs and symptoms associated with this condition include abdominal pain, diarrhea, and dehydration. The infections commonly involved in viral gastroenteritis are rotavirus, norovirus, and adenovirus, which spread through the fecal-oral and contact routes and cause non-bloody diarrhea. These infections can affect both immunocompetent and immunocompromised individuals. Since the pandemic in 2019, coronavirus gastroenteritis has increased in incidence and prevalence. Morbidity and mortality rates from viral gastroenteritis have declined significantly over the years due to early recognition, treatment with oral rehydration salts, and prompt vaccination. Improved sanitation measures have also played a key role in reducing the transmission of infection. In addition to viral hepatitis causing liver disease, herpes virus, and cytomegalovirus are responsible for ulcerative GI disease. They are associated with bloody diarrhea and commonly occur in im-munocompromised individuals. Hepatitis viruses, Epstein-Barr virus, herpesvirus 8, and human papillomavirus have been involved in benign and malignant diseases. This mini review aims to list different viruses affecting the GI tract. It will cover common symptoms aiding in diagnosis and various important aspects of each viral infection that can aid diagnosis and management. This will help primary care physicians and hospitalists diagnose and treat patients more easily.

Deer mastadenovirus B pneumonia in a white-tailed deer fawn.

A 7-mo-old farmed white-tailed deer fawn (Odocoileus virginianus) died after several weeks of progressive deterioration associated with endoparasitism and respiratory signs. A field autopsy was performed, and lung tissue was submitted for histologic examination. The findings were consistent with necrosuppurative bronchointerstitial pneumonia with intranuclear viral inclusions. Immunofluorescence using fluorescently labeled polyclonal antibodies to bovine adenovirus 3 and 5 was positive. To rule out cross-reactivity with other adenoviruses, formalin-fixed, paraffin-embedded tissue sections were submitted for genome sequence analysis, which revealed a 99.6% match to Deer mastadenovirus B (formerly Odocoileus adenovirus 2, OdAdV2). To our knowledge, natural clinical disease associated with OdAdV2 has not been reported previously.

[Antiviral and virucidal activity of sodium deoxyribonucleate and its complex with iron against viruses of different kingdoms and families].

INTRODUCTION: The urgent problem of modern medicine is the fight against acute respiratory viral infections (ARVI). To combat ARVI, drugs of wide antiviral potency are needed, as well as immunomodulating drugs. Such antiviral and immunomodulatory effects has sodium deoxyribonucleate (DNA-Na) and its complex with iron (DNA-Na-Fe) developed on the basis of double-stranded DNA of natural origin. AIM OF THE STUDY: To assess antiviral and virucidal activity of DNA-Na and DNA-Na-Fe against viruses of different kingdoms and families. MATERIALS AND METHODS: Antiviral and virucidal activity of DNA-Na and DNA-Na-Fe was assessed in cell cultures infected with viruses. RESULTS AND DISCUSSION: DNA-Na and DNA-Na-Fe had antiviral activity against adenovirus at concentrations of 2501000 mcg/ml. Antiviral effect of both drugs was not detected in case of poliovirus. DNA-Na and DNA-Na-Fe had antiviral activity against coronavirus in all administration schemes. EC50 for DNA-Na ~ 2500 mcg/ml, for DNA-Na-Fe ~ 1000 mcg/ml. In cells treated with DNA-Na-Fe, secretion of following proinflammatory cytokines was detected: Interleukin (IL) 1, IL-2, IL-6, IL-18, interferon- (IFN-), IFN-, as well as anti-inflammatory cytokines: IL-4, IL-10, antagonist of IL-1 receptor. Evidently, DNA-Na and DNA-Na-Fe have antiviral effect, but mechanism of action does not seem to be associated with specific effect on viral replication. Presence of virucidal activity of drugs against representatives of Coronaviridae, Adenoviridae, Picornaviridae, Retroviridae, Herpesviridae in vitro test in range of 1.03.0 lg TCID50 was identified. CONCLUSION: Presence of simultaneous antiviral and virucidal activity of DNA-Na and DNA-Na-Fe against adeno- and coronaviruses shows their prospects for prevention and treatment of ARVI.

Immunogenicity Differences of the ChAdOx1 nCoV-19 Vaccine According to Pre-Existing Adenovirus Immunity.

This study investigated the immunogenicity of, and reactogenicity to, the ChAdOx1 nCoV-19 vaccine according to pre-existing adenovirus immunity. Individuals scheduled for COVID-19 vaccination were prospectively enrolled in a tertiary hospital with 2400 beds from March 2020 onwards. Pre-existing adenovirus immunity data was obtained before ChAdOx1 nCoV-19 vaccination. A total of 68 adult patients administered two doses of the ChAdOx1 nCoV-19 vaccine were enrolled. Pre-existing adenovirus immunity was identified in 49 patients (72.1%), but not in the remaining 19 patients (27.9%). The geometric mean titer of S-specific IgG antibodies was statistically higher in individuals without pre-existing adenovirus immunity at several time points: before the second ChAdOx1 nCoV-19 dose (56.4 (36.6-125.0) vs. 51.0 (17.9-122.3), p = 0.024), 2-3 weeks after the second ChAdOx1 nCoV-19 dose (629.5 (451.5-926.5) vs. 555.0 (287.3-926.0), p = 0.049), and 3 months after the second ChAdOx1 nCoV-19 dose (274.5 (160.5-655.3) vs. 176.0 (94.3-255.3), p = 0.033). In the absence of pre-existing adenovirus immunity, systemic events were observed with higher frequency, especially chills (73.7% vs. 31.9%, p = 0.002). In conclusion, individuals without pre-existing adenovirus immunity showed a higher immune response to ChAdOx1 nCoV-19 vaccination and a higher frequency of reactogenicity to ChAdOx1 nCoV-19 vaccination was observed.

Detection of human Mastadenovirus C in wild guinea pigs (Cavia aperea aperea) feces.

The Adenoviridae family is composed by a high diversity of viruses that are extremely resistant in environment and are frequently excreted in animal reservoir feces for long periods. The knowledge of adenovirus (AdV) diversity among wild species may be important for the understanding of the epidemiology of putative emerging diseases. Cavia aperea aperea, commonly known as wild guinea pigs, wild cavies, or preas, are small herbivorous rodents widely distributed throughout South America and classified in Caviidae family, as well as domestic guinea pigs and capybaras. In order to investigate their potential role as reservoir of zoonotic agents, the present study aimed to verify the presence of AdV in fecal samples of 14 preas from Northeast Brazil. When submitted to nested PCR, two out of 14 samples (14.28%) were positive for AdV and classified as human Mastadenovirus C (HAdV-C) using DNA sequencing and phylogenetic analysis. Wild guinea pigs are synanthropic rodents that live in close contact with humans. The investigation of viral agents in rodents is important due to their potential role as reservoirs of human and animal pathogens. Moreover, the present work presents the first known evidence of HAdV in wild guinea pig stool samples, which may represent both the impact of anthropogenic pollution to wild animals and an important knowledge in terms of human health.

[Serenity and objectivity in the face of severe childhood hepatitis: the diagnostic challenge]. / Serenidad y objetividad ante la hepatitis grave infantil: el reto diagnóstico.

The appearance of acute hepatitis of unknown aetiology in children has set off alarms in the World Health Organization and in member countries; identifying it and studying it lay out a diagnostic challenge for first-contact medical personnel and especially for pediatricians of Mexico, as well as for the coordination of care in health services. The international outlook and an analysis of the clinical manifestations are described, as well as key points for the identification and an observation of the samples that are requested for their study in Mexico.

La aparición de la hepatitis aguda infantil de etiología desconocida ha hecho que suenen las alarmas en la Organización Mundial de la Salud y en los países miembros; su identificación y estudio plantean un reto diagnóstico para el personal médico de primer contacto y en especial para los pediatras del país, así como para la coordinación de la atención en los servicios de salud. Se describe el panorama internacional y un análisis de las manifestaciones clínicas y los puntos clave para su identificación, así como una observación a las muestras que se solicitan para su estudio en México.

ICTV Virus Taxonomy Profile: Adenoviridae 2022.

The family Adenoviridae includes non-enveloped viruses with linear dsDNA genomes of 25-48 kb and medium-sized icosahedral capsids. Adenoviruses have been discovered in vertebrates from fish to humans. The family is divided into six genera, each of which is more common in certain animal groups. The outcome of infection may vary from subclinical to lethal disease. This is a summary of the ICTV Report on the family Adenoviridae, which is available at ictv.global/report/adenoviridae.

Proposed mechanism for rare thrombotic events after use of some Covid-19 vaccines.

Administration of AstraZeneca/Oxford and Johnson & Johnson/Janssen Covid-19 vaccines which use an adenovirus vector for DNA delivery has been associated with very rare thromboembolic complications coupled with an immune response to platelet factor 4 protein. The cause of this has not yet been identified. It is known that binding of coagulation factor proteins to the surface of some adenoviruses can protect their function. Here I propose that the thromboembolic events are caused by impairment of coagulation factor X binding to the virus capsid. The unprotected capsid then stimulates an immune response leading to platelet activation, increased thrombogenicity and formation of an antibody complex with platelet factor 4. Impaired binding of factor X may be due to an undiagnosed mutation in affected individuals. Options to test this mechanism experimentally and potential remedial actions to resolve the hazard are described. This mechanism offers a remedial route to address concerns about the safety of these vaccines, which are otherwise well-positioned to deliver global Covid-19 immunity across diverse healthcare economies.

Outbreak of Acute Respiratory Illness Associated With Human Adenovirus Type 4 at the United States Coast Guard Academy, 2019.

BACKGROUND: Although a human adenovirus (HAdV) vaccine is available for military use, officers-in-training are not routinely vaccinated. We describe an HAdV-associated respiratory outbreak among unvaccinated cadets at the US Coast Guard Academy and its impact on cadet training. METHODS: We defined a case as a cadet with new onset cough or sore throat during August 1-October 4, 2019. We reviewed medical records and distributed a questionnaire to identify cases and to estimate impact on cadet training. We performed real-time polymerase chain reaction testing on patient and environmental samples and whole genome sequencing on a subset of positive patient samples. RESULTS: Among the 1072 cadets, 378 (35%) cases were identified by medical records (n = 230) or additionally by the questionnaire (n = 148). Of the 230 cases identified from medical records, 138 (60%) were male and 226 (98%) had no underlying conditions. From questionnaire responses, 113 of 228 (50%) cases reported duty restrictions. Of cases with respiratory specimens, 36 of 50 (72%) were HAdV positive; all 14 sequenced specimens were HAdV-4a1. Sixteen (89%) of 18 environmental specimens from the cadet dormitory were HAdV-positive. CONCLUSIONS: The HAdV-4-associated outbreak infected a substantial number of cadets and significantly impacted cadet training. Routine vaccination could prevent HAdV respiratory outbreaks in this population.

Infección grave diseminada por adenovirus en receptores de trasplante hepático / Severe adenovirus infections in hepatic transplant recipients / Infecção grave por adenovírus disseminado em receptores de transplante de fígado

Resumen: Los adenovirus humanos continúan siendo un desafío en la práctica clínica, se trata de virus de tipo ADN, con amplia distribución en la población, causa frecuente de enfermedad autolimitada en niños. Sin embargo, en pacientes inmunosuprimidos, principalmente trasplantados de células hematopoyéticas y de órganos sólidos, puede llegar a ser causa de enfermedad diseminada severa, con elevada morbimortalidad. Compartimos el primer reporte nacional de enfermedad por adenovirus diseminado, en el que se presentan dos casos clínicos de pacientes trasplantados hepáticos, que desarrollan enfermedad diseminada grave por adenovirus. Se realiza una revisión de la literatura sobre el tema.

Abstract: Human adenoviruses still constitute a challenge in the clinical practice. These are DNA viruses that are widely disseminated among the population and often cause self-limiting diseases in children. However, it may result in a severe diseminated disease with high morbi-mortality rates in immunocompromised patients, in particular transplant recipients of hematopoietic cells and solid organs. The study shares the first national report for disseminated adenovirus disease, presenting two clinical cases of hepatic transplant recipients who developed severe disseminated adenovirus disease. And conducting a literature review on the topic.

Resumo: Os adenovírus humanos continuam sendo um desafio na prática clínica; são vírus do tipo DNA, com ampla distribuição na população, causa frequente de doença autolimitada em crianças. Entretanto, em pacientes imunossuprimidos, principalmente receptores de transplante de células hematopoiéticas e órgãos sólidos, pode se tornar causa de doença disseminada grave, com alta morbimortalidade. Este é o primeiro relato nacional de doença de adenovírus disseminado, no qual são apresentados dois casos clínicos de pacientes transplantados de fígado que desenvolvem doença de adenovírus disseminada grave. Realizou-se também revisão da literatura sobre o assunto.

Genomic Characterisation of a Highly Divergent Siadenovirus (Psittacine Siadenovirus F) from the Critically Endangered Orange-Bellied Parrot (Neophema chrysogaster).

Siadenoviruses have been detected in wild and captive birds worldwide. Only nine siadenoviruses have been fully sequenced; however, partial sequences for 30 others, many of these from wild Australian birds, are also described. Some siadenoviruses, e.g., the turkey siadenovirus A, can cause disease; however, most cause subclinical infections. An example of a siadenovirus causing predominately subclinical infections is psittacine siadenovirus 2, proposed name psittacine siadenovirus F (PsSiAdV-F), which is enzootic in the captive breeding population of the critically endangered orange-bellied parrot (OBP, Neophema chrysogaster). Here, we have fully characterised PsSiAdV-F from an OBP. The PsSiAdV-F genome is 25,392 bp in length and contained 25 putative genes. The genome architecture of PsSiAdV-F exhibited characteristics similar to members within the genus Siadenovirus; however, the novel PsSiAdV-F genome was highly divergent, showing highest and lowest sequence similarity to skua siadenovirus A (57.1%) and psittacine siadenovirus D (31.1%), respectively. Subsequent phylogenetic analyses of the novel PsSiAdV-F genome positioned the virus into a phylogenetically distinct sub-clade with all other siadenoviruses and did not show any obvious close evolutionary relationship. Importantly, the resulted tress continually demonstrated that novel PsSiAdV-F evolved prior to all known members except the frog siadenovirus A in the evolution and possibly the ancestor of the avian siadenoviruses. To date, PsSiAdV-F has not been detected in wild parrots, so further studies screening PsSiAdV-F in wild Australian parrots and generating whole genome sequences of siadenoviruses of Australian native passerine species is recommended to fill the siadenovirus evolutionary gaps.

Identification of potent epitopes on hexon capsid protein and their evaluation as vaccine candidates against infections caused by members of Adenoviridae family.

Adenoviruses cause economically important diseases in vertebrates. Effective vaccines against adenoviral diseases are currently lacking. Here, we report a highly conserved epitopic region on hexon proteins of adenoviruses that generate a strong immune response when used as a virus-like-particle (VLP) vaccine, produced by inserting the epitopic region into the core protein of hepatitis B virus. For evaluation of its protective efficacy, the epitopic region from a representative adenovirus, fowl adenovirus serotype 4 (FAdV-4), was tested as a VLP vaccine which conferred 90% protection against challenge with a virulent FAdV-4 isolate in chickens. Importantly, such a high level of protection is not achieved when the epitopic region is employed as a part of a subunit vaccine. As the sequence and the structure of the epitopic region are highly conserved in hexon proteins of adenoviruses, the epitopic region could be employed as a promising VLP vaccine candidate against adenoviral diseases, in general.

Non-Norovirus Viral Gastroenteritis Outbreaks Reported to the National Outbreak Reporting System, USA, 2009-2018.

During 2009-2018, four adenovirus, 10 astrovirus, 123 rotavirus, and 107 sapovirus gastroenteritis outbreaks were reported to the US National Outbreak Reporting System (annual median 30 outbreaks). Most were attributable to person-to-person transmission in long-term care facilities, daycares, and schools. Investigations of norovirus-negative gastroenteritis outbreaks should include testing for these viruses.