Hospital outbreak of human respiratory syncytial virus (HRSV) illness in immunocompromised hospitalized children during summer

Changing respiratory pathogens infection patterns after COVID-19 pandemic in Shanghai, China

To assess the positive rate of 11 respiratory pathogens in 2023, providing a comprehensive summary and analysis of the respiratory infection patterns after COVID-19 pandemic. The study comprised 7544 inpatients suspected of respiratory infections who underwent respiratory pathogen multiplex polymerase chain reaction tests from July 2022 to December 31, 2023. We analyzed the positive rate of 11 pathogens over 18 months and the characterization of infection patterns among different age groups and immune states. Among 7544 patients (age range 4 months to 104 years, 44.99% female), the incidence of infected by at least one of the 11 pathogens was 26.07%. Children (55.18%, p < 0.05) experienced a significantly higher infection probability than adults (20.88%) and old (20.66%). Influenza A virus (8.63%), Mycoplasma pneumoniae (5.47%), and human rhinovirus (5.12%) were the most common pathogens. In children, M. pneumoniae (35.96%) replaced the predominant role of human respiratory syncytial virus (HRSV) (5.91%) in the pathogen spectrum. Age, immunosuppressed state, and respiratory chronic conditions were associated with a significantly higher risk of mixed infection. Immunosuppressed patients were more vulnerable to human coronavirus (4.64% vs. 1.65%, p < 0.05), human parainfluenza virus (3.46% vs. 1.69%, p < 0.05), and HRSV (2.27% vs. 0.55%, p < 0.05). Patterns in respiratory infections changed following regional epidemic control measures and the COVID-19 pandemic.

Molecular investigation of human metapneumovirus in children with acute respiratory infections in Chennai, South India, from 2016-2018

Human metapneumovirus (hMPV) has emerged as a frequent cause of acute respiratory infections (ARI) among young children. The prevalence and genetic diversity of hMPV circulating in Chennai, Southern India, has not been studied yet. Hence, this study was aimed to investigate the prevalence, co-infection with other respiratory viruses like HRSV A and B, influenza A and B, hRV and HPIV 1-4 viruses, socio-demographic associations, and genotypes of hMPV among children in Chennai. A total of 350 nasal swab specimens were collected from children with ARI during April 2016 to August 2018 and tested for hMPV by real time PCR method. In this study, hMPV was detected in 4% (14/350) of the samples. One hMPV positive sample was found to be co-infected with influenza B virus. The mean and median ages of the children with hMPV infection were 61.5 months (5.1 years) and 83 months (6.9 years), respectively. Phylogenetic analysis of the partial F gene revealed the presence of A2c subcluster among the study strains as well as with B1 and B2 lineages. The prevalence data obtained in this study is important in evaluating the role of hMPV in childhood ARI and emphasizes the importance of routine viral diagnosis in hospitals. To the best of our knowledge, this is the first study to report the prevalence, seasonality, and genetic diversity of hMPV in Chennai as well as the first study to report A2c subcluster of hMPV among children in India.

Newly Diagnosed Acute Myeloid Leukemia in a Patient With Severe SARS-CoV-2 Infection

We present a 68-year-old male patient with persistent and complicated SARS-CoV-2 infection who was diagnosed with acute myeloid leukemia (AML). The patient suffered from fever, cough and progressive dyspnea for 10 days and he was admitted to the intensive care unit due to respiratory failure and cytokine release syndrome (CRS). Despite a transient improvement of CRS by the implementation of supportive care, including also the administration of recombinant tissue plasminogen activator (rt-PA) and tocilizumab, his clinical course worsened over time. Thus, a bone marrow aspiration was performed revealing the presence of myeloblasts in a proportion of 32% and flow cytometry confirmed the diagnosis of AML-M1 according to FAB classification. Re-evaluation of peripheral blood tests revealed that the patient was admitted with anemia and thrombocytopenia that were never recovered during hospitalization. Due to the patient's poor clinical condition, no chemotherapy was applied, and he died of sepsis and multi-organ failure two days later. This case suggests that in all patients with a persistent and/or complicated infection, even during pandemics, the presence of an underlying hematologic malignancy should always be taken into consideration.

Molecular characteristics and successful management of a respiratory syncytial virus outbreak among pediatric patients with hemato-oncological disease

Background

Respiratory syncytial virus (RSV) is responsible for upper and lower respiratory tract infection in adults and children. Especially immunocompromised patients are at high risk for a severe course of infection, and mortality is increased. Moreover RSV can spread in healthcare settings and can cause outbreaks. Herein we demonstrate the successful control and characteristics of a RSV outbreak that included 8 patients in our Department of Pediatric Hematology and Oncology.

Methods

We performed an epidemiologic investigation and a molecular analysis of the outbreak strains. Moreover we present the outbreak control bundle and our concept for RSV screening in the winter season.

Results

RSV A and B strains caused the outbreak. RSV B strains affected 3 patients, 2 of whom were co-infected with RSV A. Exactly this RSV A strain was detected in another 5 patients. Our multimodal infection control bundle including prophylactic RSV screening was able to rapidly stop the outbreak.

Conclusion

An infection control bundle in RSV outbreaks should address all potential transmission pathways. In pediatric settings the restriction of social activities might have a temporal negative impact on quality of life but helps to limit transmission opportunities. Molecular analysis allows better understanding of RSV outbreaks and, if done in a timely manner, might be helpful for guidance of infection control measures.

The clinical and phylogenetic investigation for a nosocomial outbreak of respiratory syncytial virus infection in an adult hemato-oncology unit

Although many reports have already shown RSV outbreaks among hemato-oncology patients, genomic studies detecting similar RSV strains prior to an outbreak in the hospital are rare. In 2014, the University of the Ryukyus hospital hemato-oncology unit experienced, and successfully managed, a respiratory syncytial virus (RSV) nosocomial outbreak. During the outbreak investigation, genotyping and phylogenetic analysis was used to identify a potential source for the outbreak. Nasopharyngeal swabs were tested for RSV using three tests: (1) rapid antigen test (RAT); (2) reverse transcriptase polymerase chain reaction (PCR); or (3) quantitative PCR (RT-qPCR); a positive PCR reaction was considered a confirmed case of RSV. Phylogenetic analysis of the G protein was performed for outbreak and reference samples from non-outbreak periods of the same year. In total, 12 confirmed cases were identified, including 8 hemato-oncology patients. Patient samples were collected weekly, until all confirmed RSV cases returned RSV negative test results. Median time of suspected viral shedding was 16 days (n = 5, range: 8-37 days). Sensitivity and specificity of the RAT compared with RT-qPCR were 30% and 91% (n = 42). Phylogenetic analysis revealed nine genetically identical strains; eight occurring during the outbreak time period and one strain was detected 1 month prior. A genetically similar RSV detected 1 month before is considered one potential source of this outbreak. As such, healthcare providers should always enforce standard precautions, especially in the hemato-oncology unit.

Prevalence of Human metapneumovirus infection among patients with influenza-like illness: Report from a Tertiary Care Centre, Southern India

BACKGROUND

Human metapneumovirus (HMPV), discovered in the 21st century, has emerged as an important cause of influenza-like illness in children and adults causing mild upper respiratory tract infection to severe bronchiolitis and community-associated pneumonia. The aim of this study was to determine the prevalence of HMPV in the Union Territory of Puducherry, India, as part of National Influenza Surveillance Programme.

MATERIALS AND METHODS

From November 2011 to December 2013, a total of 447 nasopharyngeal samples were collected from patients with acute respiratory infections and tested for HMPV RNA by real-time polymerase chain reaction.

RESULTS

HMPV was identified in 23/447 (5%) samples with 11/23 in the age group of 14-30 years. Most of the HMPV infections were mild with no fatalities. Two patients were co-infected with the respiratory syncytial virus and one with influenza B virus. The seasonal distribution showed increasing HMPV infection cases in rainy months except for a peak in summer of 2012. Phylogenetic analysis based on the sequences of the nucleoprotein gene of one HMPV strain showed a high degree of sequence identity with Indian strains obtained during 2006 and 2011.

CONCLUSION

This study shows that HMPV infection is more common in adults than in children. Sequence homology suggests the circulation of closely related HMPV strains within the country.

In silico approach towards designing virtual oligopeptides for HRSV

HRSV (human respiratory syncytial virus) is a serious cause of lower respiratory tract illness in infants and young children. Designing inhibitors from the proteins involved in virus replication and infection process provides target for new therapeutic treatments. In the present study, in silico docking was performed using motavizumab as a template to design motavizumab derived oligopeptides for developing novel anti-HRSV agents. Additional simulations were conducted to study the conformational propensities of the oligopeptides and confirmed the hypothesis that the designed oligopeptide is highly flexible and capable of assuming stable confirmation. Our study demonstrated the best specific interaction of GEKKLVEAPKS oligopeptide for glycoprotein strain A among various screened oligopeptides. Encouraged by the results, we expect that the proposed scheme will provide rational choices for antibody reengineering which is useful for systematically identifying the possible ways to improve efficacy of existing antibody drugs.