Acute gastroenteritis outbreak associated with multiple and rare norovirus genotypes after storm events in Santa Catarina, Brazil.

Norovirus is a major cause of acute diarrheal disease (ADD) outbreaks worldwide. In the present study, we investigated an ADD outbreak caused by norovirus in several municipalities of Santa Catarina state during the summer season, southern Brazil in 2023. As of the 10th epidemiological week of 2023, approximately 87 000 ADD cases were reported, with the capital, Florianópolis, recording the highest number of cases throughout the weeks. By using RT-qPCR and sequencing, we detected 10 different genotypes, from both genogroups (G) I and II. Some rare genotypes were also identified. Additionally, rotavirus and human adenovirus were sporadically detected among the ADD cases. Several features of the outbreak suggest that sewage-contaminated water could played a role in the surge of ADD cases. Storm events in Santa Catarina state that preceded the outbreak likely increased the discharge of contaminated wastewater and stormwater into water bodies, such as rivers and beaches during a high touristic season in the state. Climate change-induced extreme weather events, including intensified rainfall and frequent floods, can disturb healthcare and sanitation systems. Implementing public policies for effective sanitation, particularly during peak times, is crucial to maintain environmental equilibrium and counter marine pollution.

Investigation of cytokine polymorphisms on viral infections after renal transplantation exhibit association between IFN-γ +874 A > T and CMV manifestations.

We investigated the effects of TNF-α, IFN-γ, IL-10 polymorphisms on viral infections (CMV, BKPyV, HHV-6, EBV) after renal transplantation. IFN-γ+874 A > T (lower IFN production) was associated with CMV disease (p = .039) in patients under mycophenolate-based therapy and graft failure (p = .025). This study underscores the role of IFN-γ+874 SNP in CMV infection.

Clinical Manifestations and Complications of Children With COVID-19 Compared to Other Respiratory Viral Infections: A Cohort Inpatient Study From Rio de Janeiro, Brazil.

Introduction: The coronavirus disease-2019 (COVID-19) clinical manifestations in children and adolescents are diverse, despite the respiratory condition being the main presentation. Factors such as comorbidities and other respiratory infections may play a role in the initial presentation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aims to describe the epidemiological aspects, clinical, and laboratory manifestations of pediatric patients admitted to a tertiary pediatric hospital in Rio de Janeiro, diagnosed with COVID-19, and compare these with other viral conditions during the first year of the SARS-CoV-2 pandemic. Methods: All patients under 18 years of age that were admitted with upper airway infection were enrolled and followed up for 30 days. The main dependent variable was the laboratorial diagnosis of SARS-CoV-2, and independent variables were studied through logistic regression. Results: A total of 533 patients were recruited, and 105 had confirmed SARS-CoV-2 infection. Detection of other viruses occurred in 34% of 264 tested participants. Six patients died (two in SARS-CoV-2 infected group). The variables independently associated with COVID-19 were older age (OR = 1.1, 95% CI = 1.0-1.1), lower leukocytes count at entry (OR = 0.9, 95% CI = 0.8-0.9), and contact with suspected case (OR = 1.6, 95% CI = 1.0-2.6). Patients with COVID-19 presented higher odds to be admitted in an intensive care unit (OR = 1.99, 95% CI = 1.08-3.66). Conclusions: Even during the SARS-CoV-2 pandemic, several other respiratory viruses were present in admitted pediatric patients. Variables associated with COVID-19 infection were older age, lower leukocytes count at entry, and a domiciliary suspect contact. Although patients with COVID-19 were more frequently admitted to ICU, we did not observe higher mortality in this group.

Neurological Manifestations Associated With SARS-CoV-2 in Children: A Case Series.

Neurological manifestations of COVID-19 may affect both central and peripheral nervous systems. Unlike in adults, in whom majority of severe cases derive from respiratory complications, neurological involvement is one of the main causes of severe COVID-19 in children. This study aimed to detect viral respiratory pathogens, mainly SARS-CoV-2, in nasopharynx and cerebrospinal fluid samples utilizing qRT-PCR (TaqMan) in a pediatric population in Brazil. We evaluated four children with neurological symptoms and laboratory-confirmed SARS-CoV-2 infection: three presenting with meningoencephalitis and one presenting with Guillain-Barré syndrome. All four patients had mild respiratory symptoms. SARS-CoV-2 RNA was identified in two cerebrospinal fluid samples. SARS-CoV-2 involvement should be considered for differential diagnosis in pediatric cases presenting neurological alterations even if symptoms such as headache, anosmia, or dizziness are absent.

Genomic surveillance of SARS-CoV-2 Spike gene by sanger sequencing.

The SARS-CoV-2 responsible for the ongoing COVID pandemic reveals particular evolutionary dynamics and an extensive polymorphism, mainly in Spike gene. Monitoring the S gene mutations is crucial for successful controlling measures and detecting variants that can evade vaccine immunity. Even after the costs reduction resulting from the pandemic, the new generation sequencing methodologies remain unavailable to a large number of scientific groups. Therefore, to support the urgent surveillance of SARS-CoV-2 S gene, this work describes a new feasible protocol for complete nucleotide sequencing of the S gene using the Sanger technique. Such a methodology could be easily adopted by any laboratory with experience in sequencing, adding to effective surveillance of SARS-CoV-2 spreading and evolution.

Human Bocavirus in Brazil: Molecular Epidemiology, Viral Load and Co-Infections.

Human bocavirus (HBoV) is an emerging virus and has been detected worldwide, especially in pediatric patients with respiratory and gastrointestinal infection. In this study, we describe HBoV prevalence, genotypes circulation and DNA shedding, in stool samples from children up to two years of age in Brazil. During 2016 and 2017, 886 acute gastroenteritis (AGE) stool samples from ten Brazilian states were analyzed by TaqMan®-based qPCR, to detect and quantify HBoV. Positive samples were genotyped by sequencing the VP1/2 overlap region, followed by phylogenetic analysis and co-infections were accessed by screening other gastroenteric viruses. HBoV was detected in 12.4% (n = 110) of samples, with viral load ranging from 1.6 × 102 to 1.2 × 109 genome copies per gram of stool. From these, co-infections were found in 79.1%, and a statistically lower HBoV viral load was found compared to viral loads of rotavirus, norovirus and adenovirus in double infected patients (p < 0.05). No significant differences were found between HBoV viral load in single or co-infections, age groups or genotypes. Phylogenetic analysis identified the circulation of HBoV-1 in 38%, HBoV-2 in 40% and HBoV-3 in 22%. Continuous HBoV monitoring is needed to clarify its role in diarrhea disease, especially in the absence of classic gastroenteric viruses.

Investigation of three oncogenic epitheliotropic viruses shows human papillomavirus in association with non-melanoma skin cancer.

Non-melanoma skin cancers (NMSC) share similar risk factors with other virus-related cancers, despite the lack of proved causal association between viral infection and NMSC development. We investigated the presence of Merkel cell polyomavirus (MCPyV), Epstein-Barr virus (EBV), and human papillomavirus (HPV) DNA in 83 NMSC fresh-frozen and 16 non-cancerous skin biopsies and evaluated viral infection according to demographical data, histopathological diagnosis, and ultraviolet exposure. Our results showed that 75% of NMSC biopsies were positive for at least one out of three viruses, whereas only 38% of non-cancerous skin biopsies were positive (p = 0.02). Notably, HPV detection was frequent in NMSC (43%) and nearly absent (one sample, 6.7%) in non-cancerous biopsies (p = 0.007). MCPyV was associated with sites of higher exposure to ultraviolet radiation (p = 0.010), while EBV was associated with a compromised immune system (p = 0.032). Our study showed that HPV was strongly associated with NMSC while EBV and MCPyV with other risk factors. Though further studies are required to elucidate the role of viral infection in NMSC development and management, this study supports the possible role of oncogenic viruses in skin cancers, especially HPV.

A globally applicable PCR-based detection and discrimination of BK and JC polyomaviruses.

BKV and JCV belong to the Polyomaviridae family and are opportunistic agents associated with complications in immunocompromised individuals. Although a single screening assay for both viruses would be convenient, the diversity of BKV and JCV serotypes and genotypes is a methodological challenge. In this paper, we developed a PCR method able to detect and segregate BKV and JCV, despite these genetic discrepancies. A duplex semi-nested PCR (duplex snPCR) was designed to target a conserved region (639nt-1516nt) within the VP2 gene. In the first PCR, a primer set common to all BKV and JCV serotypes/ genotypes was used, followed by a semi-nested PCR with internal primers for BKV and JCV segregation. The limit of detection of the duplex snPCR was as low as 10 copies of BKV or JCV plasmids/µL. Specific products were observed when JCV and BKV plasmids were mixed in the same reaction. In field sample testing, the duplex snPCR detected and distinguished both viruses in different biological samples. Results were confirmed by Sanger's sequencing. The geographical complexity of BKV and JCV serotypes and genotypes imposes limits to a simple and universal method that could detect each virus. However, we describe here a sensitive and reliable PCR technique for BKV and JCV diagnosis that overcomes these limitations and could be universally applied.

Adenovirus species C detection in children under four years of age with acute bronchiolitis or recurrent wheezing.

BACKGROUND: Lower respiratory tract viral infection is an important cause of morbidity and mortality in children worldwide. Among viral etiological agents the human Adenovirus (AdV) has been associated to mild or severe respiratory tract infection. OBJECTIVE: To detect the presence of human Adenovirus (AdV) in children with acute bronchiolitis or recurrent wheezing, describing their clinical features and determining Adenovirus species and AdV association to Respiratory Syncytial Virus (RSV), Human Metapneumovirus (MPV) and Parainfluenza virus (PIV). STUDY DESIGN: A total of 155 children bellow 48 months of age with acute bronchiolitis or recurrent wheezing were investigated for the presence of AdV, RSV, MPV and PIV in nasopharyngeal aspirate, by real-time PCR method. RESULTS: AdV, predominantly of species C, has been detected as the unique pathogen (AdVi) or in association to other pathogens (AdVa.), in 39/155 samples. Crackles were more frequent in children with AdV. RSVi was detected predominantly in children with acute bronchiolitis while AdVi and AdVa were detected more frequently in patients with recurrent wheezing. CONCLUSION: A small outbreak of AdV species C was observed in 2012 and 2013. AdV was detected more frequently in children with recurrent wheezing while RSVi was more frequent in infants with acute bronchiolitis.

An immunofluorescence test for diagnosis of ophthalmic herpes in a mouse corneal model.

Herpes simplex virus type 1 (HSV-1) ophthalmic disease is the most common cause of corneal blindness in humans world-wide. Current culture techniques for HSV take several days and commercially available HSV laboratory based diagnostic techniques vary in sensitivity. Our study was conducted to evaluate the use of a quicker and simpler method to herpes ophthalmic diagnosis. Corneal smears were made by firm imprints of infected mouse eyes to glass slides, after smears were fixated with cold acetone, and an indirect immunofluorescence (IIF) method was performed using monoclonal antibodies in a murine model of ophthalmic herpes. Eye swabs from infected mice were inoculated in Vero cells for virus isolation. Cytology and histology of the eye were also performed, using hematoxylin-eosin routine. Mouse eyes were examined by slit-lamp biomicroscopy for evidence of herpetic disease at various times postinoculation. We made a comparative evaluation of sensitivity, specificity and speed of methods for laboratory detection of HSV. Our results indicate that this IIF method is quick, sensitive, specific and can be useful in the diagnosis of ophthalmic herpes as demonstrated in an animal model.

An immunofluorescence test for diagnosis of ophthalmic herpes in a mouse corneal model

Herpes simplex virus type 1 (HSV-1) ophthalmic disease is the most common cause of corneal blindness in humans world-wide. Current culture techniques for HSV take several days and commercially available HSV laboratory based diagnostic techniques vary in sensitivity. Our study was conducted to evaluate the use of a quicker and simpler method to herpes ophthalmic diagnosis. Corneal smears were made by firm imprints of infected mouse eyes to glass slides, after smears were fixated with cold acetone, and an indirect immunofluorescence (IIF) method was performed using monoclonal antibodies in a murine model of ophthalmic herpes. Eye swabs from infected mice were inoculated in Vero cells for virus isolation. Cytology and histology of the eye were also performed, using hematoxylin-eosin routine. Mouse eyes were examined by slit-lamp biomicroscopy for evidence of herpetic disease at various times postinoculation. We made a comparative evaluation of sensitivity, specificity and speed of methods for laboratory detection of HSV. Our results indicate that this IIF method is quick, sensitive, specific and can be useful in the diagnosis of ophthalmic herpes as demonstrated in an animal model.

A doença oftálmica do vírus herpes simplex do tipo 1 (HSV-1) é a causa mais comum de cegueira córnea em humanos mundialmente. Técnicas de cultura atuais para HSV levam vários dias e laboratórios de HSV comercialmente disponíveis estabelecem que as técnicas diagnósticas variam em sensibilidade. Nosso estudo foi conduzido para avaliar a aplicação prática de um método mais rápido e simples para diagnosticar o herpes oftálmico. Decalques córneos foram feitos por impressões firmes de olhos de camundongos a lâminas de vidro, depois os decalques foram fixados com acetona fria, e um método de imunofluorescência indireta (IIF) foi executado empregando anticorpos monoclonais no modelo murino de herpes oftálmico. Swabs de córnea foram inoculados em células Vero para o isolamento de vírus a partir de camundongos infectados. A citologia e a histologia do olho foi feita pela rotina de hematoxilina e eosina. Os olhos de camundongos foram examinados através de oftalmomicroscopia para evidência de doença herpética em vários tempos pós-inoculação. A avaliação comparativa da sensibilidade, especificidade e velocidade de métodos para detecção laboratorial de HSV foi feita. Nossos resultados indicam que este método de IIF é rápido, sensível, específico e pode ser útil no diagnóstico de herpes oftálmico como demonstrado no modelo animal.