Comparison of 11 respiratory pathogens among hospitalized children before and during the COVID-19 epidemic in Shenzhen, China.

BACKGROUND: The effect of SARS-CoV-2 on existing respiratory pathogens in circulation remains uncertain. This study aimed to assess the impact of SARS-CoV-2 on the prevalence of respiratory pathogens among hospitalized children. METHODS: This study enrolled hospitalized children with acute respiratory infections in Shenzhen Children's Hospital from September to December 2019 (before the COVID-19 epidemic) and those from September to December 2020 (during the COVID-19 epidemic). Nasopharyngeal swabs were collected, and respiratory pathogens were detected using multiplex PCR. The absolute case number and detection rates of 11 pathogens were collected and analyzed. RESULTS: A total of 5696 children with respiratory tract infection received multiplex PCR examination for respiratory pathogens: 2298 from September to December 2019 and 3398 from September to December 2020. At least one pathogen was detected in 1850 (80.5%) patients in 2019, and in 2380 (70.0%) patients in 2020; the detection rate in 2020 was significantly lower than that in 2019.The Influenza A (InfA) detection rate was 5.6% in 2019, but 0% in 2020. The detection rates of Mycoplasma pneumoniae, Human adenovirus, and Human rhinovirus also decreased from 20% (460), 8.9% (206), and 41.8% (961) in 2019 to 1.0% (37), 2.1% (77), and 25.6% (873) in 2020, respectively. In contrast, the detection rates of Human respiratory syncytial virus, Human parainfluenza virus, and Human metapneumovirus increased from 6.6% (153), 9.9% (229), and 0.5% (12) in 2019 to 25.6% (873), 15.5% (530), and 7.2% (247) in 2020, respectively (p < 0.0001). CONCLUSIONS: Successful containment of seasonal influenza as a result of COVID-19 control measures will ensure we are better equipped to deal with future outbreaks of both influenza and COVID-19.Caused by virus competition, the detection rates of Human respiratory syncytial virus, Human parainfluenza virus, and Human metapneumovirus increased in Shenzhen,that reminds us we need to take further monitoring and preventive measures in the next epidemic season.

Respiratory viruses in the healthy middle ear and middle ear with otitis media with effusion.

To investigate the presence of respiratory viruses in the middle ear cavity of the individuals with a healthy middle ear and the children with otitis media with effusion (OME). A total of 72 middle ear samples were collected from 25 children with OME (Group 1) and 47 individuals with no middle ear disease (Group 2). Multiplex real-time polymerase chain reaction was used to investigate the presence of 20 different respiratory viruses. Virus results were compared with bacteriomes of the same populations. At least one respiratory virus was detected in 56% of the patients in Group 1 and 12.8% of the individuals in Group 2. The viral co-infection rate for Group 1 and 2 was 8% and 2.1%, respectively. In Group 1, adenovirus was the most frequently detected virus with a rate of 24%, either alone (16%) or concurrent with other viruses (8%), followed by influenza B (12%), rhinovirus, and bocavirus (8%) each. Parainfluenza 4, coronavirus OC43, and RSV A/B were detected in 4% of the sample each. In Group 2, rhinovirus was detected in two samples (4.3%) followed by adenovirus, coronavirus OC43, coronavirus E299, and coronavirus NL63 with a rate of 2.1% each. The detection rate of respiratory viruses was significantly higher in children aged 6 to 11 years. There was no positive association between virus and bacteria found in the middle ear cavity. The current study has provided comprehensive data indicating the presence of diverse respiratory viruses in the healthy middle ear cavity. Our results also suggest that respiratory viruses might have a contribution to OME pathogenesis.

CACO-2 cells: A continuous cell line with sensitive and broad-spectrum utility for respiratory virus culture.

BACKGROUND: Primary rhesus monkey kidney cells (RhMK) can be used for the detection of respiratory viruses, including influenza and parainfluenza. The human colon adeno-carcinoma cell line, CACO-2, has been previously used for the growth of multiple influenza viruses, including seasonal, novel and avian lineages. OBJECTIVE: We compared CACO-2, Madin-Darby Canine Kidney (MDCK), and RhMK cells for the isolation of viruses from patients presenting with influenza like-illness (ILI). STUDY DESIGN: Nasopharyngeal specimens from patients with ILI in primary care settings were processed for conventional viral culture in MDCK, RhMK, and CACO-2. Cells were examined microscopically for cytopathic effect (CPE) and confirmatory testing included immunofluorescent antigen (IFA) detection and real-time RT-PCR. Additionally, 16 specimens positive for respiratory syncytial virus (RSV) by PCR were inoculated on CACO-2 cells. Statistical analysis was done using Chi-square test with IBM Statistical Program. RESULTS: Of 1031 respiratory specimens inoculated, viruses were isolated and confirmed from 331 (32.1 %) in MDCK cells, 304 (29.5 %) in RhMk cells, and 433 (42.0 %) in CACO-2 cells. These included influenza A/(H1N1)pdm09, influenza A(H3N2), influenza B, parainfluenza virus (PIV) types 1, 2, and 3, human coronavirus 229E (CoV-229E), human adenovirus (HAdV), herpes simplex virus 1 (HSV 1), and enterovirus (EV). Influenza A viruses grew best in the CACO-2 cell line. Time to observation of CPE was similar for all three cell types but unlike RhMK and MDCK cells, virus-specific morphological changes were indistinguishable in CACO-2 cells. None of the 16 specimens positive for RSV by PCR grew on CACO-2 cells. CONCLUSIONS: The overall respiratory virus culture isolation rate in CACO-2 cells was significantly higher than that in RhMK or MDCK cells (p < 0.05). CACO-2 cells also supported the growth of some viruses that did not grow in either RhMK or MDCK cells. Except for RSV, CACO-2 cells provide a worthwhile addition to culture algorithms for respiratory specimens.

Viral nucleic acid analysis with PCR in lacrimal tissue and nasal swab samples of primary acquired nasolacrimal duct obstruction cases.

PURPOSE: To evaluate the role of viral infections in the pathogenesis of primary acquired nasolacrimal duct obstruction. METHODS: The study included 48 patients diagnosed with primary acquired nasolacrimal duct obstruction undergoing dacryocystorhinostomy surgery. Prior to dacryocystorhinostomy surgery, nasal swab sample was taken from the inferior meatus at the same side. During dacryocystorhinostomy, tissue biopsy sample (2 × 2 mm) was taken from the junction area of the lacrimal sac and nasolacrimal duct. Following nucleic acid extraction, polymerase chain reaction was performed. RESULTS: The patients consisted of 9 (18.8%) men and 39 (81.2%) women with a mean age of 51.0 ± 14.3 years. Qualitative polymerase chain reaction showed viral genome in the nasal swabs of 10 (20.8%) patients, including coronavirus 229E (three cases), coronavirus HKU1 (two cases), respiratory syncytial virus (two cases), coronavirus OC43 (one case), coronavirus NL63 (one case), and adenovirus (one case). In the dacryocystorhinostomy samples, viral genomes were detected in four (8.3%) cases, including respiratory syncytial virus (two cases), coronavirus HKU1 (one case), and adenovirus (one case). There was a statistically significant agreement between nasal mucosal swab and dacryocystorhinostomy biopsy samples in terms of respiratory syncytial virus positivity (kappa = 1.000, p = 0.001). CONCLUSION: Although the viral genome was detected in the samples, a direct relationship between viruses and pathogenesis of primary acquired nasolacrimal duct obstruction could not be revealed because of the low number of positive results. However, considering the profibrotic characteristics of specific viruses such as respiratory syncytial virus and adenovirus, viral infections may be one of the many predisposing factors of primary acquired nasolacrimal duct obstruction.