Severe Respiratory Infection Research Articles

Exploring Clinical Predictors of Severe Human Metapneumovirus Respiratory Tract Infections in Children: Insights from a Recent Outbreak.

Human metapneumovirus (hMPV) is an important pathogen that causes both upper (URTIs) and lower respiratory tract infections (LRTIs) in children. The virus can be implicated in severe bronchiolitis and pneumonia, necessitating hospitalization, with certain cases requiring intensive care unit intervention. As part of a retrospective observational study, we aimed to identify indicators of severe hMPV respiratory tract infections in children referred to the University Children's Hospital Ljubljana and the Department of Infectious Diseases Ljubljana, Slovenia, during a recent outbreak. We analyzed clinical data from November 2022 to January 2023 and compared the characteristics of children presenting with URTIs and LRTIs. We also examined the characteristics of children with hMPV LRTIs, distinguishing between children with and without LRTI-associated hypoxemia. Of 78 hMPV-PCR-positive pediatric patients (mean age 3.1 years; 60.3% boys), 36% had a URTI, and 64% had an LRTI. Hospitalization was required in 64% (50/78), with 42% (21/50) requiring oxygen therapy. LRTI-associated hypoxemia was more common in patients with atopy who showed dyspnea, tachypnea, crackles, and wheezing on lung auscultation. In a multivariable logistic regression analysis, wheezing detected on lung auscultation was a significant predictive factor for hypoxemic hMPV-LRTI. Specifically, children presenting with wheezing were found to be ten times more likely to experience hypoxemia. Prematurity and chronic conditions did not influence the presentation or severity of hMPV infection. This study highlights wheezing and atopy as crucial indicators of severe hMPV LRTI in children, emphasizing the importance of early recognition and intervention.

Vacunar a la embarazada puede prevenir la bronquiolitis por virus respiratorio sincitial en el lactante

Authors´ conclusions: prefusion F protein vaccine against respiratory syncytial virus administered to pregnant women in the last trimester of pregnancy prevents this virus severe respiratory infections in their infants, without important adverse effects. Reviewers´ commentary: The vaccine appears effective and safe, although its efficacy estimates are imprecise. It constitutes an alternative preventive option to the administration of nirsevimab in the newborn, with comparable impact expectations.

Impact of pneumococcal conjugate vaccine 13 introduction on severe lower respiratory tract infections associated with respiratory syncytial virus or influenza virus in hospitalized children in Ulaanbaatar, Mongolia

ObjectivesLimited data indicate a beneficial effect of pneumococcal conjugate vaccines (PCVs) on respiratory syncytial virus (RSV) and influenza infections in young children. We evaluated the impact of 13-valent PCV (PCV13) introduction on the incidence of severe lower respiratory tract infections (LRTIs) associated with RSV or influenza in hospitalized children. MethodsOur study was restricted to children aged <2 years with arterial oxygen saturation <93% and children with radiologically confirmed pneumonia nested in a pneumonia surveillance project in four districts of Ulaanbaatar city, Mongolia. We tested nasopharyngeal swabs collected on admission for RSV and influenza using quantitative reverse transcription-polymerase chain reaction. The impact of PCV13 on the incidence of LRTI outcomes associated with RSV or with influenza for the period April 2015-March 2020 was estimated. Incidence rate ratios comparing pre- and post-vaccine periods were estimated for each outcome for each district using negative binomial models and for all districts combined with a mixed-effects negative binomial model. Adjusted models accounted for seasonality. Sensitivity analyses were conducted to assess the robustness of our findings. ResultsAmong 5577 tested cases, the adjusted incidence rate ratios showed a trend toward a reduction in RSV-associated outcomes: all LRTIs (0.77, 95% confidence interval [CI] 0.44-1.36), severe LRTIs (0.88, 95% CI 0.48-1.62), very severe LRTIs (0.76, 95% CI 0.42-1.38), and radiologically confirmed pneumonia (0.66, 95% CI 0.32-1.38) but inconsistent trends in outcomes associated with influenza. ConclusionsNo significant reductions were observed in any outcomes associated with RSV and influenza after PCV introduction.

Changes in Prevalence and Seasonality of Pathogens Identified in Acute Respiratory Tract Infections in Hospitalised Individuals in Rural and Urban Settings in South Africa; 2018-2022.

Severe acute respiratory tract infections (SARIs) has been well described in South Africa with seasonal patterns described for influenza and respiratory syncytial virus (RSV), while others occur year-round (rhinovirus and adenovirus). This prospective syndromic hospital-based surveillance study describes the prevalence and impact of public interventions on the seasonality of other respiratory pathogens during the coronavirus disease-19 (COVID-19) pandemic. This occurred from August 2018 to April 2022, with 2595 patients who met the SARS case definition and 442 controls, from three sentinel urban and rural hospital sites in South Africa. Naso/oro-pharyngeal (NP/OP) swabs were tested using the FastTrack Diagnostics® Respiratory pathogens 33 (RUO) kit. Descriptive statistics, odds ratios, and univariate/multivariate analyses were used. Rhinovirus (14.80%, 228/1540) and Streptococcus pneumoniae (28.50%, 439/1540) were most frequently detected in NP/OP swabs and in children <1 years old (35%, 648/1876). Among others, pathogens associated with SARI cases causing disease were influenza A&B, HRV, RSV, hCoV 229e, Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae. Pre-COVID-19, seasonal trends of these pathogens correlated with previous years, with RSV and influenza A seasons only resuming after the national lockdown (2021). It is evident that stringent lockdown conditions have severe impacts on the prevalence of respiratory tract infections.

Multiplex PCR in Diagnosing Respiratory Tract Infections in Hospitalized Children.

To elaborate the utility of multiplex quantitative polymerase chain reaction (multiplex qPCR) for the accurate diagnosis of severe respiratory tract infections (RTIs) in hospitalized children. In two separate periods during 2022, 76 respiratory specimens (combined throat/nasopharyngeal swabs) were submitted for multiplex qPCR regarding 26 respiratory pathogens. The specimens were obtained from children with severe RTIs hospitalized in the Institute for Respiratory Diseases in Children, Skopje. Multiplex qPCR detected at least one respiratory pathogen in all examined specimens (76/76), with 83% (63/76) rate of co-infections. Considering that positive results are only the ones with Ct value below 28, the rates of detected pathogens and co-infections decrease to 75% and 22%, respectively. The most commonly detected pathogens during the spring period were Parainfluenza type 3 (PIV3) followed by Adenovirus (AdV) and Respiratory syncytial virus type B (RSVB) with frequency rate of 23%, 19% and 19%, respectively. During the autumn period, the most common were RSVB and Streptococcus pneumoniae with frequency rate of 31% and 17%, respectively. Multiplex qPCR is a powerful tool for diagnosing RTIs. Semi-quantification of the viral load by reporting Ct values added higher level of evidence for accurate diagnosis. Seasonal detection of the examined viruses was notable with higher prevalence of PIV3 in spring and RSVB in autumn period.

Nirsevimab: A Review.

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in people of all ages and is the leading cause of hospitalization among infants in the United States. The year 2023 was exciting for RSV prevention. The Food and Drug Administration (FDA) approved 3 new tools for preventing severe lower respiratory tract RSV infections in infants, young children, and elderly persons. In May 2023, the FDA approved 2 vaccines, RSVpreF3 (Arexvy™, GSK) and RSVpreF (Abrysvo™, Pfizer), for adults ages 60 years or older to be given as a single-dose intramuscular injection. July 2023 brought the approval of the first long-acting monoclonal antibody nirsevimab (Beyfortus™, Sanofi and AstraZeneca) for the prevention of RSV disease in infants and young children. Then in August, the FDA approved a vaccine (Abrysvo™, Pfizer) to be given to pregnant women to protect their newborns through passive immunity. This article focuses on nirsevemab that has been recommended by the Advisory Committee on Immunization Practices (ACIP) and American Academy of Pediatrics (AAP) to be administered for all infants <8 months of age and for children 8 to 19 months of age who are at increased risk for severe RSV disease.

Evaluation of Risk Factors for Children with Severe Adenovirus Respiratory Infection: Retrospective Study

Background: Human adenovirus (HAdV) commonly affects children hospitalized with any form of respiratory infection (RI). Severe HAdV infection leads to one of the most serious types of infantile RI, with rapidly progressive illness and a poor prognosis. Objectives: This study investigated the relationship between aspartate aminotransferase (AST) levels and the severity of HAdV RI in children. Methods: We collected clinical data from 665 cases of HAdV RI in children hospitalized at the pediatric ward of Changde First People's Hospital between January and December 2019. We analyzed the relationship between AST levels and disease severity. Results: Of the 665 HAdV-positive cases, 89.8% were &lt; 6 years of age. Among them, upper RI was diagnosed in 18.8% of cases, bronchiolitis in 4.8%, and mild pneumonia in 48.1%. Severe pneumonia was observed in 28.2% of cases. The 665 patients in the cohort were divided into a mild group (n = 477 cases, 71.73%) and a severe group (n = 188 cases, 28.27%). Univariate analysis showed that children with severe HAdV RI had a lower age of onset and lower hemoglobin and serum albumin levels while having higher platelet counts, lactic acid dehydrogenase, creatine kinase, creatine kinase isoenzyme, alanine aminotransferase, and AST levels compared to those with mild infections (P &lt; 0.05). Multivariate analysis revealed that these factors were related to disease severity (P &lt; 0.05). The ROC curve analysis indicated that the area under the AST curve was 0.782. When the intercept value was 52.5 U/L, the sensitivity was 60.6%, and the specificity was 83.4%. Conclusions: Serum AST levels can serve as a predictor of adenoviral RI severity in children.

A robust, scalable, and cost-efficient approach to whole genome sequencing of RSV directly from clinical samples.

Respiratory syncytial virus (RSV) is a leading cause of severe acute respiratory tract infections in children and the elderly, and its prevention has become an increasing priority. Recently, vaccines and a long-acting monoclonal antibody to protect effectively against severe disease have been approved for the first time. Hence, there is an urgent need for genomic surveillance of RSV at the global scale to monitor virus evolution, especially with an eye toward immune evasion. However, robust, cost-effective methods for RSV whole genome sequencing that are suitable for high-throughput of clinical samples are currently scarce. Therefore, we have developed Next-RSV-SEQ, an experimental and computational pipeline that produces reliably high-quality RSV genomes directly from clinical specimens and isolates.

SunGold Kiwifruit Consumption Restores Adequate to Optimal Vitamin C Status in People with a History of Severe Respiratory Infections.

Severe respiratory infections are characterised by depleted vitamin C and elevated inflammation and oxidative stress. The aim of this study was to recruit people with a history of severe respiratory infections to undergo a six-week intervention with SunGold kiwifruit to determine if this could restore adequate vitamin C status. Secondary outcomes included changes in inflammatory and oxidative stress biomarkers, self-reported fatigue and subjective mood, and the incidence, duration and severity of respiratory symptoms. The total cohort comprised 20 adults (65% female, age range 31-84 years). The participants had a low median fruit and vegetable intake of 2.3 servings/day and a correspondingly low vitamin C intake of 46 mg/day. Circulating vitamin C status was a median of 45 µmol/L and was in the hypovitaminosis range in 25% of the cohort. Following intervention with two SunGold kiwifruit/day (equivalent to ~300 mg vitamin C), there was an increase in plasma vitamin C concentrations to >60 µmol/L (p < 0.05). Approximately 20% of the participants were unable to reach adequate vitamin C status (≥50 µmol/L), possibly due to current smoking, which enhances vitamin C turnover, and a strong inverse correlation between body weight and vitamin C status (r = -0.734, p < 0.05). Following the intervention, there were indications towards decreases in the inflammatory biomarkers C-reactive protein and TNFα (p > 0.05), but no changes in oxidative stress biomarkers (F2isoprostanes, protein carbonyls). There were decreases in fatigue and depression (p < 0.05) and a lower number of individual respiratory symptoms reported during the kiwifruit intervention phase (8.5 vs. 10, p = 0.05). Overall, the consumption of two SunGold kiwifruit per day for six weeks was able to restore adequate to saturating vitamin C status in ~80% of the participants. Smokers and people with higher body weight may need larger doses and/or longer duration of supplementation. The contribution of vitamin C to reducing fatigue, depression, and number of respiratory symptoms warrants further investigation.

Quando il polmone ci suggerisce una immunodeficienza

A 10-day-old neonate affected by a severe respiratory infection was eventually diagnosed with severe combined immunodeficiency with hyper-IgE (Job syndrome).

Personalized Infant Risk Prediction for Severe Respiratory Syncytial Virus Lower Respiratory Tract Infection Requiring Intensive Care Unit Admission.

Currently, there are no available tools to identify infants at the highest risk of significant morbidity and mortality from respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) who would benefit most from RSV prevention products. The objective was to develop and internally validate a personalized risk prediction tool for use among all newborns that uses readily available birth/postnatal data to predict RSV LRTI requiring intensive care unit (ICU) admission. We conducted a population-based birth cohort study of infants born from 1995 to 2007, insured by the Tennessee Medicaid Program, and who did not receive RSV immunoprophylaxis during the first year of life. The primary outcome was severe RSV LRTI requiring ICU admission during the first year of life. We built a multivariable logistic regression model including demographic and clinical variables available at or shortly after birth to predict the primary outcome. In a population-based sample of 429 365 infants, 713 (0.2%) had severe RSV LRTI requiring ICU admission. The median age of admission was 66 days (interquartile range, 37-120). Our tool, including 19 variables, demonstrated good predictive accuracy (area under the curve, 0.78; 95% confidence interval, 0.77-0.80) and identified infants who did not qualify for palivizumab, based on American Academy of Pediatrics guidelines, but had higher predicted risk levels than infants who qualified (27% of noneligible infants with >0.16% predicted probabilities [lower quartile for eligible infants]). We developed a personalized tool that identified infants at increased risk for severe RSV LRTI requiring ICU admission, expected to benefit most from immunoprophylaxis.

Breath Markers of Oxidative Stress in Children with Severe Viral Lower Respiratory Tract Infection.

Severe viral lower respiratory tract infection (LRTI), resulting in both acute and long-term pulmonary disease, constitutes a substantial burden among young children. Viral LRTI triggers local oxidative stress pathways by infection and inflammation, and supportive care in the pediatric intensive care unit may further aggravate oxidative injury. The main goal of this exploratory study was to identify and monitor breath markers linked to oxidative stress in children over the disease course of severe viral LRTI. Exhaled breath was sampled during invasive ventilation, and volatile organic compounds (VOCs) were analyzed using gas chromatography and mass spectrometry. VOCs were selected in an untargeted principal component analysis and assessed for change over time. In addition, identified VOCs were correlated with clinical parameters. Seventy breath samples from 21 patients were analyzed. A total of 15 VOCs were identified that contributed the most to the explained variance of breath markers. Of these 15 VOCs, 10 were previously linked to pathways of oxidative stress. Eight VOCs, including seven alkanes and methyl alkanes, significantly decreased from the initial phase of ventilation to the day of extubation. No correlation was observed with the administered oxygen dose, whereas six VOCs showed a poor to strong positive correlation with driving pressure. In this prospective study of children with severe viral LRTI, the majority of VOCs that were most important for the explained variance mirrored clinical improvement. These breath markers could potentially help monitor the pulmonary oxidative status in these patients, but further research with other objective measures of pulmonary injury is required.

Assessing the impact of COVID-19 on epidemiological changes of severe pediatric respiratory syncytial virus infections in Malaysia.

Respiratory syncytial virus (RSV) is one of the leading causes of hospitalization and mortality among children with respiratory tract infections. The non-pharmaceutical preventive measures against severe acute respiratory syndrome coronavirus (COVID-19) may have reduced the transmission of RSV, altering its tropical epidemiological seasonality. Thus, this study represents the first attempt to evaluate changes in RSV epidemiology in the context of COVID-19 pandemic in Malaysia. Conducted at a tertiary hospital in Kuala Lumpur, Malaysia, this retrospective study analyzed collated data of children aged <12 years who were admitted for severe respiratory infections from 2017 to 2022. Time series models were used to predict the differences between actual and forecasted RSV cases, while logistic regression assessed the statistical association between RSV and COVID-19. Among the 4,084 children analyzed, we reported a significant inverse relationship between RSV and COVID-19 infections during the pandemic (2020-2021) (p < 0.05). In 2020, the RSV positivity rate sharply declined to 8.3 and 5.9%, respectively, in the two prominent seasons. Time series analysis showed a tremendous decrease in cases compared to the expected values, with reductions of 98.3% in the first season and 95.7% in the second season. However, following the lifting of the restriction order in 2022, RSV infections rose sharply with a positivity rate of 36.3%, higher than pre-COVID-19 pandemic levels. This study provides evidence of increasing RSV cases post-COVID-19 pandemic, due to immunity debt. Hence, the healthcare system must be prepared to address future RSV outbreaks with the appropriate implementation of prophylaxis and public health measures.

Risk Factors for Severe Respiratory Syncytial Virus Infection in Hospitalized Children.

Respiratory syncytial virus (RSV) is a common cause of bronchiolitis and pneumonia in infants and young children. Starting in December 2010, RSV monoclonal antibody (RSV mAb) was endorsed by Taiwan National Health Insurance and given to children with prematurity and/or congenital heart diseases, which are considered high-risk factors for severe RSV diseases. Investigating other important contributing risk factors is warranted. We conducted a cohort study at National Taiwan University Hospital to determine the rate of severe outcomes among children hospitalized due to RSV infection from 2008 to 2018. Adjusted for age, sex and birth cohorts born before and after RSV mAb endorsement, we identified risk factors for severe RSV infection, defined as the requirement of invasive ventilator support. There were 1985 admissions due to RSV infections. Among them, 66 patients (3.3%) had severe RSV infection. The proportion of severe RSV infections decreased significantly after RSV mAb endorsement. Multivariable analysis revealed that age <1.5 months and cardiovascular and congenital/genetic diseases were high-risk underlying conditions. In addition, bacterial coinfections, elevated creatinine levels and initial abnormal chest radiograph findings posed warning signs for severe RSV infection. Children younger than 1.5 months of age with cardiovascular or congenital/genetic diseases were predisposed to severe RSV infection and might benefit from RSV mAb prophylaxis.

Optimization of an allelic discrimination real-time RT-PCR assay for detection of H275Y oseltamivir resistance gene mutation among influenza A(H1N1)pdm09 patients from 2020 to 2022.

Influenza virus is known to cause mild to severe respiratory infections and is also prone to genetic mutations. Of all the mutations, neuraminidase (NA) gene mutations are a matter of concern, as most approved antivirals target this protein. During the 2020 influenza season, an emergence of mutation in the NA gene, affecting the binding of the World Health Organization (WHO)-recommended probes to the specific site of the NA gene, was reported by our group. As a result of this mutation, the WHO-recommended allelic discrimination real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay was unable to detect wild-type (H275) or mutant oseltamivir-resistant (Y275) strains of influenza A(H1N1)pmd09 viruses. In the current study, the WHO-recommended probes were redesigned according to the mutation in the probe binding site. Fifty undetermined samples (2020-2021) from the previous study were retested with the newly designed probes and found to be positive for H275 and/or Y275. The results obtained were similar to the Sanger sequencing results from the previous study, suggesting that the redesigned probes were efficient in discriminating between wild-type and mutant-type viruses. Furthermore, 133 samples from 2022, making a total of 183 samples (2020-2022), were tested using improved allelic discrimination real-time RT-PCR, and the overall prevalence rate of oseltamivir resistance in 2020-2022 was found to be 0.54%.

Influenza virus infection enhances tumour-specific CD8+ T-cell immunity, facilitating tumour control.

Influenza A virus (IAV) can cause severe respiratory infection leading to significant global morbidity and mortality through seasonal epidemics. Likewise, the constantly increasing number of cancer diseases is a growing problem. Nevertheless, the understanding of the mutual interactions of the immune responses between cancer and infection is still very vague. Therefore, it is important to understand the immunological cross talk between cancer and IAV infection. In several preclinical mouse models of cancer, including melanoma and colorectal cancer, we observed that IAV infection in the lung significantly decreased the tumour burden. Concomitantly, tumour-specific CD8+ T-cells are strongly activated upon infection, both in the tumour tissue and in the lung. CD8+ T-cell depletion during infection reverses the reduced tumour growth. Interestingly, IAV infection orchestrated the migration of tumour-specific CD8+ T-cells from the tumour into the infected lung. Blocking the migration of CD8+ T-cells prevented the anti-tumoural effect. Thus, our findings show that viral respiratory infection has significant impact on the anti-tumour CD8+ T-cell response, which will significantly improve our understanding of the immunological cross talk between cancer and infection.

Genomic Expedition: Deciphering Human Adenovirus Strains from the 2023 Outbreak in West Bengal, India: Insights into Viral Evolution and Molecular Epidemiology.

Understanding the genetic dynamics of circulating Human Adenovirus (HAdV) types is pivotal for effectively managing outbreaks and devising targeted interventions. During the West Bengal outbreak of 2022-2023, an investigation into the genetic characteristics and outbreak potential of circulating HAdV types was conducted. Twenty-four randomly selected samples underwent whole-genome sequencing. Analysis revealed a prevalent recombinant strain, merging type 3 and type 7 of human mastadenovirus B1 (HAd-B1) species, indicating the emergence of recent strains of species B in India. Furthermore, distinctions in VA-RNAs and the E3 region suggested that current circulating strains of human mastadenovirus B1 (HAd-B1) possess the capacity to evade host immunity, endure longer within hosts, and cause severe respiratory infections. This study underscores the significance of evaluating the complete genome sequence of HAdV isolates to glean insights into their outbreak potential and the severity of associated illnesses.

Modulating effect of Eunkyo-san on expression of inflammatory cytokines and angiotensin-converting enzyme 2 in human mast cells.

Eunkyo-san is widely used in the treatment of severe respiratory infections. Mast cells not only serve as host cells for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but also they also exacerbate Coronavirus disease in 2019 (COVID-19) by causing a cytokine storm. Here we investigated whether Eunkyo-san and its active compound naringenin regulate the expression of inflammatory cytokines and factors connected to viral infection in activated human mast cell line, HMC-1 cells. Eunkyo-san and naringenin significantly reduced levels of inflammatory cytokines including interleukin (IL)-1β, IL-6, IL-8, thymic stromal lymphopoietin, and tumor necrosis factor-α without impacting cytotoxicity. Eunkyo-san and naringenin reduced levels of factors connected to SARS-CoV-2 infection such as angiotensin-converting enzyme 2 (ACE2, SARS-CoV-2 receptor), transmembrane protease/serine subfamily member 2, and tryptase in activated HMC-1 cells. Treatment with Eunkyo-san and naringenin considerably reduced expression levels of ACE2 transcription factor, AP-1 (C-JUN and C-FOS) by blocking phosphatidylinositide-3-kinase and c-Jun NH2-terminal kinases signaling pathways. In addition, Eunkyo-san and naringenin effectively suppressed activation of signal transducer and activator of transcription 3, nuclear translocation of nuclear factor-κB, and activation of caspase-1 in activated HMC-1 cells. Furthermore, Eunkyo-san and naringenin reduced expression of ACE2 mRNA in two activated mast cell lines, RBL-2H3 and IC-2 cells. The overall study findings showed that Eunkyo-san diminished the expression levels of inflammatory cytokines and ACE2, and these findings imply that Eunkyo-san is able to effectively mitigating the cytokine storm brought on by SARS-CoV-2 infection.

Basic therapeutic approaches to the management of hematology/oncology patients with new coronavirus infection (COVID-19)

In December 2019, cases of severe respiratory infection were reported in Wuhan, China. The disease was caused by a new, previously undescribed coronavirus, structurally similar to the then known SARS-CoV virus. The World Health Organization has named the new virus SARS-CoV-2 and the disease it causes COVID-19. The problem of COVID-19 is exacerbated by the rapid spread of the SARS-CoV-2 virus and the development of life-threatening complications, the main of which is pneumonia. Due to the severity of the condition, from 5 to 10 % of patients are treated in intensive care units.SARS-CoV-2 initially attacks the respiratory system and causes symptoms such as fever, vomiting, headache, dizziness, general weakness, and diarrhea. Then these symptoms intensify in different directions, and the disease can often lead to death.Initially, only a few methods of symptomatic treatment were available and clinical trials of drugs that had previously shown their effectiveness against infection with the MERS-CoV and SARS-CoV viruses began. Temporary recommendations have appeared suggesting the use of some drugs both in monotherapy and in combination.In patients with hematologic malignancies, the immune response to the SARS-CoV-2 coronavirus is significantly reduced, which explains the high mortality rate (up to 38 %) of these patients hospitalized for SARS-CoV-2 infection. Recently, antiviral drugs and monoclonal antibodies have become available for pre- or post-exposure prophylaxis, as well as for early treatment of COVID-19. These treatments should be offered to patients at high risk of severe COVID-19 and to those who have not responded to vaccination. However, as changes in the genetic structure of the virus accumulate, some treatments may lose their clinical effectiveness against new variants.The combination of hematological malignancies and new coronavirus infection causes a more severe course of COVID-19 compared to the population and high mortality. Factors for an unfavorable prognosis for new coronavirus infection in patients with hematological malignancies include age over 60 years, a high comorbidity index, diagnoses such as acute leukemia, especially acute myeloid leukemia and myelodysplastic syndrome, disease status (relapse, progression, as well as newly diagnosed acute leukemia), severe COVID-19, agranulocytosis (myelotoxic or tumor).

Opinion: The optimal use of risk factors to guide palivizumab prophylaxis against severe respiratory syncytial virus infection in moderate-to-late preterm infants.

Opinion: The optimal use of risk factors to guide palivizumab prophylaxis against severe respiratory syncytial virus infection in moderate-to-late preterm infants.