Low circulation of Influenza A and coinfection with SARS-CoV-2 among other respiratory viruses during the COVID-19 pandemic in a region of southern Brazil.

With the arrival of coronavirus disease 2019 (COVID-19) in Brazil in February 2020, several preventive measures were taken by the population aiming to avoid severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection including the use of masks, social distancing, and frequent hand washing then, these measures may have contributed to preventing infection also by other respiratory viruses. Our goal was to determine the frequencies of Influenza A and B viruses (FLUAV/FLUBV), human mastadenovirus C (HAdV-C), Enterovirus 68 (EV-68), and rhinovirus (RV) besides SARS-CoV-2 among hospitalized patients suspect of COVID-19 with cases of acute respiratory disease syndrome (ARDS) in the period of March to December 2020 and to detect possible coinfections among them. Nucleic acid detection was performed using reverse-transcription quantitative polymerase chain reaction (RT-qPCR) in respiratory samples using naso-oropharyngeal swabs and bronchoalveolar lavage. A total of 418 samples of the 987 analyzed (42.3%) were positive for SARS-CoV-2, 16 (1.62%) samples were positive for FLUAV, no sample was positive for FLUBV or EV-68, 67 (6.78%) samples were positive for HAdV-C, 55 samples were positive for RV 1/2 (26.3%) and 37 for RV 2/2 (13.6%). Coinfections were also detected, including a triple coinfection with SARS-CoV-2, FLUAV, and HAdV-C. In the present work, a very low frequency of FLUV was reported among hospitalized patients with ARDS compared to the past years, probably due to preventive measures taken to avoid COVID-19 and the high influenza vaccination coverage in the region in which this study was performed.

Clinical and epidemiological features of respiratory virus infections in preschool children over two consecutive influenza seasons in southern Brazil.

This study reports the results of a systematic screening for respiratory viruses in pediatric outpatients from an emergency department (ED) in southern Brazil during two consecutive influenza seasons. Children eligible for enrollment in this study were aged 24-59 months and presented with acute respiratory symptoms and fever. Naso- and oropharyngeal swabs were collected and multiplex reverse transcription PCR (RT-PCR) was performed to identify the respiratory viruses involved. In total, 492 children were included in this study: 248 in 2010 and 244 in 2011. In 2010, 136 samples (55%) were found to be positive for at least one virus and the most frequently detected viruses were human rhinovirus (HRV) (18%), adenovirus (AdV) (13%), and human coronavirus (CoV) (5%). In 2011, 158 samples (65%) were found to be positive for at least one virus, and the most frequently detected were HRV (29%), AdV (12%), and enterovirus (9%). Further, the presence of asthma (OR, 3.17; 95% CI, 1.86-5.46) was independently associated with HRV infection, whereas fever was associated with AdV (OR, 3.86; 95% CI, 1.31-16.52) and influenza infections (OR, 3.74; 95% CI, 1.26-16.06). Ten patients (2%) were diagnosed with pneumonia, and six of these tested positive for viral infection (4 HRV, 1 RSV, and 1 AdV). Thus, this study identified the most common respiratory viruses found in preschool children in the study region and demonstrated their high frequency, highlighting the need for improved data collection, and case management in order to stimulate preventive measures against these infections. J. Med. Virol. 88:1325-1333, 2016. © 2016 Wiley Periodicals, Inc.

Adenovirus 2, Bordetella bronchiseptica, and Parainfluenza Molecular Diagnostic Assay Results in Puppies After vaccination with Modified Live Vaccines.

BACKGROUND: Canine adenovirus 2, parainfluenza, and Bordetella bronchiseptica cause respiratory disease in dogs, and each has a modified live intranasal vaccine available. Molecular diagnostic assays to amplify specific nucleic acids are available for each of these agents. If positive molecular diagnostic assay results are common after vaccination, the positive predictive value of the diagnostic assays for disease would be decreased. OBJECTIVE: To determine the impact of administration of commercially available modified live topical adenovirus 2, B. bronchiseptica, and parainfluenza vaccine has on the results of a commercially available PCR panel. ANIMALS: Eight puppies from a research breeding facility negative for these pathogens. METHODS: Blinded prospective pilot study. Puppies were vaccinated with a single dose of modified live topical adenovirus 2, B. bronchiseptica, and parainfluenza and parenteral dose of adenovirus 2, canine distemper virus, and parvovirus. Nasal and pharyngeal swabs were collected on multiple days and submitted for PCR assay. RESULTS: Nucleic acids of all 3 organisms contained in the topical vaccine were detected from both samples multiple times through 28 days after vaccination with higher numbers of positive samples detected between days 3 and 10 after vaccination. CONCLUSIONS AND CLINICAL IMPORTANCE: Vaccine status should be considered when interpreting respiratory agent PCR results if modified live vaccines have been used. Development of quantitative PCR and wild-type sequencing are necessary to improve positive predictive value of these assays by distinguishing vaccinate from natural infection.

Profilaxis de infección por virus respiratorios en niños y adultos sometidos a trasplante de órganos sólidos y precursores hematopoyéticos / Prophylaxis against respiratory viral disease in pediatric and adult patients undergoing solid organ and hematopoietic stem cells transplantation

Respiratory viruses have been identified as a cause of morbidity and mortality in patients undergoing SOT and HSCT, specially in children. The most frequent are respiratory syncytial virus (RSV), influenza (FLU), parainfluenza (PI) and adenovirus (ADV). These infections are associated with progression to severe lower respiratory tract infections in up to 60% of the cases. It is advised to apply universal protection recommendations for respiratory viruses (A2) and some specific measures for FLU and AD. FLU: Annual anti-influenza vaccination (from 4-6 months post-transplantation in SOT, 6 months in HSCT (A2)); post- exposure prophylaxis in FLU (oseltamivir for 10 days (B2)). In lung transplantion, the prophylaxis should last as long as the risk period (B2). ADV: There is no vaccine nor valid chemoprophylaxis strategy to prevent ADV disease. In some specific HSCT recipients, weekly PCR monitoring is recommended until day+100 (A3).

Los virus respiratorios se han identificado como causa de morbi-mortalidad en pacientes sometidos a TOS y TPH, particularmente en pediatría. Los más frecuentes son virus respiratorio sincicial (VRS), influenza (FLU), parainfluenza (PI) y adenovirus (ADV). La fuente de contagio está en la comunidad y en el hospital afectando al paciente en cualquier período post-trasplante. Se describe progresión a infecciones graves del tracto respiratorio bajo hasta en 60 % de los casos. Se recomienda aplicar medidas de aislamiento de precaución universal para todos los virus respiratorios (A2) y se describen algunas medidas específicas para FLU y AlDV. Vacunación anti-influenza anual con vacuna inactivada (en TOS a partir de 4-6 meses post-trasplante (A2), en TPH a partir de 6 meses (A2)); profilaxis post exposición a virus FLU (oseltamivir durante 10 días (B2)). En trasplante de pulmón, la duración de la profilaxis se extenderá mientras dure el período de riesgo (B2). Con respecto a ADV, no se dispone de una vacuna adecuada y no existe a la fecha una estrategia validada de quimioprofilaxis para prevenir enfermedad por ADV; en casos específicos de TPH pediátrico, se recomienda vigilancia semanal con RPC en sangre periférica hasta el día +100 post-TPH (A3).

[Prophylaxis against respiratory viral disease in pediatric and adult patients undergoing solid organ and hematopoietic stem cells transplantation]. / Profilaxis de infection por virus respiratorios en niños y adultos sometidos a trasplante de órganos sólidos y precursores hematopoyéticos.

Respiratory viruses have been identified as a cause of morbidity and mortality in patients undergoing SOT and HSCT, specially in children. The most frequent are respiratory syncytial virus (RSV), influenza (FLU), parainfluenza (PI) and adenovirus (ADV). These infections are associated with progression to severe lower respiratory tract infections in up to 60% of the cases. It is advised to apply universal protection recommendations for respiratory viruses (A2) and some specific measures for FLU and AD. FLU: Annual anti-influenza vaccination (from 4-6 months post-transplantation in SOT, 6 months in HSCT (A2)); post- exposure prophylaxis in FLU (oseltamivir for 10 days (B2)). In lung transplantion, the prophylaxis should last as long as the risk period (B2). ADV: There is no vaccine nor valid chemoprophylaxis strategy to prevent ADV disease. In some specific HSCT recipients, weekly PCR monitoring is recommended until day+100 (A3).

[Experimental vaccines against avian inclusion body hepatitis. I. Serological evaluation]. / Vacunas experimentales contra hepatitis A cuerpo de inclusión aviar. I. Valoración serológica.

Two Inclusion Body Hepatitis (IBH) vaccines (Vac-19 and Vac-28) were elaborated from serotypes 4, 10 and 11, isolated from country field outbreaks. The strains were attenuated by passages in embryonating SPF chicken eggs (16 and 22 passages for both vaccines) and in kidney cell culture (3 and 6 passages respectively). Four experimental groups (G) were used: G I and G II of 8 chickens each, vaccinated orally (4,4 TCID50/ml) with Vac-19 and Vac-28 respectively, at the third week and re-vaccinated 35 days later with the same dose and method. Groups G III and G IV with 5 chickens each were the positive and negative controls, both group were not vaccinated, the first only challenged wit a pool of the 4, 10 and 11 serotypes on 45 days old and the last was not challenged. Prior and afterward, vaccination and challenge, clinical and serological exams were performed. The immune response was determined trough Agar Gel Precipitin (AGP) and serum neutralization (SN) test in chicken kidney cells (CKC) using the beta method (200 TCID50/50 microliters). Positive response (100%) was detected from day 43 onward in the vaccinated group, to AGP test. This situation occurred on day 55 for the challenged group (G III). Geometric mean titres (GMT) were, prior to challenge, 1.194 for G I and 23.525 for G II. After challenge, GMT were 7.760 and > or = 305.736 respectively. The GMT for G III was 640. No clinical signs or mortality were observed during the experiment. The conclusion is that only Vac-28 provided a partial protection to the fowl, measured through the lesions observed.