Clinical manifestations and risk factors for mortality of patients with severe influenza during the 2016–2018 season

Nucleic acid-based electrochemical biosensor for detection of influenza B by gold nanoparticles

The influenza virus is a pervasive pathogen that exhibits increased prevalence during colder seasons, resulting in a significant annual occurrence of infections. Notably, pharmaceutical interventions effective against influenza A strains often exhibit limited efficacy against influenza B variants. Against this backdrop, the need for innovative approaches to accurately and swiftly differentiate and detect influenza B becomes evident. Biosensors play a pivotal role in this detection process, offering rapid, specific, and sensitive identification of the virus, facilitating timely intervention and containment efforts. Oligonucleotide sequences targeting the conserved B/Victoria/2/87 influenza virus NP region were designed. Nasopharyngeal swabs were collected from patients suspected of influenza virus infection, and viral RNA was extracted. RNA quality was assessed through one-step PCR. cDNA synthesis was performed using random hexamers, and real-time PCR quantified the influenza genome. Gold nanoparticles were immobilized on a surface to immobilize the specific DNA probe, and electrochemical hybridization was electrochemically followed. The biosensor exhibited high selectivity and effective distinction of complementary sequences from mismatches and influenza virus cDNA genome. The biosensor successfully detected the influenza B virus genome in real samples. Non-influenza samples yielded no significant hybridization signals. The comparison between the results obtained from the biosensor and real-time PCR revealed full agreement of these methods. The biosensor utilized electrochemical detection of hybridization and proved effective in detecting the influenza B virus genome with high specificity, sensitivity, and selectivity. Comparative analysis with real-time PCR underscored the accuracy and potential applicability of the biosensor in rapid and specific virus detection. This innovative approach holds promise for future diagnostic and epidemiological applications in detecting influenza B virus and other pathogens.

Analysis of clinical characteristics and risk factors for death due to severe influenza in children

OBJECTIVE

The study analyzed the clinical features of children who had severe influenza and discussed on the risk factors associated with death in this population.

METHODS

A total of 167 children with severe influenza admitted to the intensive care unit of our hospital from January 2018 to August 2023 were selected and divided into the death group (27 cases) and the survival group (140 cases). Demographic characteristics and clinical data were collected and compared between the two groups. Logistic regression analysis was used to explore the risk factors for death in children with severe influenza.

RESULTS

The male-to-female ratio of the 167 children with severe influenza was 2.21:1, the median age was 3 years, and influenza A accounted for 70.66%. The CD4+ T cells percentage and CD4/CD8 were lower in the death group; the percentage of comorbid underlying diseases, mechanical ventilation, other systemic involvement, comorbid associated encephalopathy or encephalitis, and red blood cell distribution width (RDW), lactate dehydrogenase, activated partial thromboplastin time (APTT), and interleukin 6 were higher in the death group. The mechanical ventilation, associated encephalopathy or encephalitis, RDW, APTT, and CD4/CD8 were the independent risk factors for death.

CONCLUSION

Mechanical ventilation, comorbid encephalopathy or encephalitis, increased RDW, prolonged APTT, and decreased CD4/CD8 are independent risk factors for death in children with severe influenza.

Prevalence and Predictors for Respiratory Viral Infections among Liver Disease Patients

Aim and background

Respiratory viral infections (RVIs) cause significant hospitalizations every year. Also, RVIs caused by either influenza or noninfluenza group of viruses can have adverse outcomes, especially among immunosuppressed patients. Regular and timely supervision is needed for accurate etiological identification, to prevent inappropriate use of antibiotics in patients with nonbacterial etiology. This study aimed to identify the spectrum of RVIs and clinical characteristics among liver disease patients with influenza-like illness (ILI).

Materials and methods

In this study, medical records of patients with ILI, whose requests for respiratory viral testing came from September 2016 to December 2022 were retrospectively reviewed. Respiratory viruses were identified using FilmArray 2.0 respiratory panel (BioFire Diagnostics, USA).

Results

Of the 1,577 liver disease patients with ILI, the overall prevalence of RVI was 28% (n = 449). Infection by noninfluenza viruses (NIVs) was detected in 329 patients (73%), higher than those infected with influenza viruses. In multivariable logistic regression analysis, female gender [odds ratio (OR): 2.5, 95% confidence interval (CI): 1.5-4.2], infection with influenza B (OR: 3.3, 95% CI: 1.09-9.9) and decompensated cirrhosis (OR: 3.9, 95% CI: 1.7-8.5) were independent risk factors for mortality. Regarding seasonality, influenza peaked in monsoons and winters, whereas NIVs circulated throughout the year.

Conclusion

Overall, this study adds new knowledge regarding the incidence of RVI and the distribution of respiratory viral etiologies among liver disease patients with ILI. The findings highlight that female gender, decompensated cirrhosis, and influenza B infection are independently associated with poor clinical outcomes. Early etiological identification of viral causes of ILI could aid in an enhanced understanding of the prevalence of ILI and the timely management of the patients.

Clinical significance

Respiratory viral infections can cause severe illness in individuals with underlying liver disease. Accurate diagnosis and risk stratification is crucial in mitigating the adverse health effects.

How to cite this article

Samal J, Prabhakar T, Prasad M, et al. Prevalence and Predictors for Respiratory Viral Infections among Liver Disease Patients. Euroasian J Hepato-Gastroenterol 2023;13(2):108-114.

Vaccination in liver diseases and liver Transplantation: Recommendations, implications and opportunities in the post-covid era

The interest in vaccination efficacy and toxicity has surged following the Covid-19 pandemic. Immune responses to several vaccines have been shown to be suboptimal in patients with chronic liver disease (CLD) or post-liver transplant (LT), as a consequence of cirrhosis-associated immune dysfunction (CAID) or post-LT immunosuppression respectively. Accordingly, vaccine-preventable infections may be more common or severe than in the general population. The Covid-19 pandemic has greatly accelerated research and development into vaccination technology and platforms, which will have spillover benefits for liver patients. The aims of this review are: (i) to discuss the impact of vaccine-preventable infections on CLD and post-LT patients, (ii) to appraise current evidence supporting vaccination strategies, and (iii) to provide some insight into recent developments relevant for liver patients.

Vaccination in Chronic Liver Disease: An Update

Patients with chronic liver disease (CLD) with or without cirrhosis remain at risk of developing hepatic decompensation when infected with viral or bacterial pathogens. The Advisory Committee on Immunization Practices (ACIP) currently recommends vaccination in CLD against hepatitis A virus (HAV), hepatitis B virus (HBV), influenza, pneumococcus, herpes zoster, tetanus, diphtheria, pertussis, and SARS-CoV-2. Inactivated vaccines are preferred over live attenuated ones, especially in transplant recipients where live vaccines are contraindicated. As the severity of the liver disease progresses, vaccine efficacy declines, and therefore, vaccines should be ideally administered early in the disease course for optimal immune response. Despite the strong recommendations, overall vaccination coverage in CLD remains poor; however, it is encouraging to note that in recent years coverage against influenza and pneumococcus has shown some improvement. Inadequate access to healthcare, lack of information on vaccine safety, poor financial reimbursement for healthcare providers, and vaccine misinformation are often responsible for low immunization rates. This review summarizes the impact of vaccine-preventable illness in those with CLD, updated vaccine guidelines, seroconversion rates in the vaccinated, and barriers faced by healthcare professionals in immunizing those with liver disease.

Clinical manifestations of influenza and performance of rapid influenza diagnostic test: A university hospital setting

BACKGROUND

Rapid influenza diagnostic test (RIDT) is a diagnostic tool that detects the influenza virus nucleoprotein antigen. The RIDT is widely used in clinical practice because it is simple and cost-effective, and provides results within 10-15 minutes.

OBJECTIVE

We aimed at evaluating the sensitivity and specificity of the Sofia® RIDT compared with the Luminex® multiplex polymerase chain reaction (PCR). The other goal was to determine the predicting factors for diagnosing influenza among individuals with influenza-like illness (ILI).

METHOD

Patients with ILI who had the results of both tests were retrospectively reviewed. We determined the performances of the RIDT.

RESULTS

A total of 473 patients were included with a median age of 58 (interquartile range 41-74) years. Of these, 47.1% were male, and 16.2% were diagnosed with influenza by the RIDT or RT-PCR's positive test. For influenza A, the RIDT showed a sensitivity of 76.3% (95% confidence interval [CI] 59.8-88.6) and a specificity of 97.9% (95% CI 96.1-99.0), whereas for influenza B, it showed a sensitivity of 47.1% (95% CI 23.0-72.2) and a specificity of 97.1% (95% CI 95.2-98.5). Patients with influenza were more likely to present with fever (81.8% vs 63.1%), cough (81.8% vs 66.1%), and rhinorrhea (41.6% vs 26.5%) compared to those without influenza (P < 0.05, all), and had a higher proportion of pneumonia (19.5% vs 10.6%, P = 0.029) and acute respiratory distress syndrome (5.2% vs 1.5%, P = 0.063). The predicting factors for influenza among patients presented with ILI were cough (odds ratio [OR] 2.77; 95% CI 0.21-0.81, P = 0.010), rhinorrhea (OR 1.87; 95% CI 1.03-3.36, P = 0.037), and higher body temperature (OR 1.64; 95% CI 1.23-2.19, P = 0.001).

CONCLUSIONS

The sensitivity of the RIDT for the diagnosis of influenza is fair in contrast to the specificity. Among patients with ILI, cough, rhinorrhea, and higher body temperature might be factors for predicting influenza.

Risk Factors of Influenza-Associated Respiratory Illnesses Reported to a Sentinel Hospital of Lahore, Pakistan: 2015-2016

Epidemiological data about determinants of influenza A virus (IAV) in the Pakistani population is scarce. We aimed to conduct a prospective hospital-based active surveillance study from October 2015 to May 2016 to identify potential risk factors associated with IAV infection among patients with influenza-like illness (ILI) and severe acute respiratory illness (SARI). Surveillance was conducted in Lahore General Hospital, selected as a sentinel site in Lahore District, Pakistan. Nasal/throat samples were collected along with epidemiological and clinical data from enrolled patients. Real-time reverse-transcription polymerase chain reaction (rRT-PCR) was performed to identify IAV and its subtypes (H1N1pdm09, H3N2). Data were analyzed to determine risk factors and risk markers associated with IAV infections. A total of 311 suspected ILI and SARI cases were enrolled in the study, and among these 50 were IAV-positive. Of these 50 confirmed cases of IAV, 14 were subtyped as H1N1pdm09 and 15 were H3N2; the remaining 21 were untyped. A final multivariable model identified four independent risk factors/markers for IAV infection: exposure history to ILI patients within last 7 days and gender being male were identified as risk factors of IAV infection, while use of antibiotics prior to hospital consultation and presence of fever were identified as risk markers. We concluded that adopting nonpharmaceutical interventions like hand hygiene, masks, social distancing, and where possible, avoiding identified risk factors could decrease the risk of IAV infection and may prevent imminent outbreaks of IAV in the community.

[COVID-19- and influenza-associated deaths in Munich as of March 2020-a standardized analysis of death certificates]

INTRODUCTION

In light of the current COVID-19 pandemic, the idea arose to conduct a study to comparatively evaluate deaths from two respiratory transmissible infectious diseases (pandemic COVID-19 and seasonal influenza) by means of death certificates received by the health department.

METHODS

Death certificates of all deaths in Munich in the death period from 1 March-31 December 2020 were analyzed. The predefined inclusion criteria were the indication of "Corona, COVID-19, SARS-CoV‑2, Influenza (A/B)" on the death certificates. Standardized data entry was performed. The collected data were analyzed descriptively in aggregated form.

RESULTS

A total of 12,441 persons died during the study period, 1029 (8.3%) from confirmed COVID-19 and 22 (0.1%) from influenza. The two collectives matched well in the parameters studied. The mean age at death was approximately 80 years and the most common site of death was in hospital. Infectious disease was the cause of death in more than 90% of cases. The most common causes of death were acute respiratory distress syndrome/respiratory failure and multiorgan failure. An average of two previous illnesses were reported, most commonly diseases of the circulatory system and nervous system. There was no influenza death in the second pandemic wave.

DISCUSSION

In this study, COVID-19- and influenza-associated deaths were compared for the first time. The deaths of both collectives matched well in the parameters studied, but still require verification in a larger study given the small numbers of influenza cases. An English full-text version of this article is available at SpringerLink as Supplementary Information.

Behavior of hospitalized severe influenza cases according to the outcome variable in Catalonia, Spain, during the 2017-2018 season

Influenza is an important cause of severe illness and death among patients with underlying medical conditions and in the elderly. The aim of this study was to investigate factors associated with ICU admission and death in patients hospitalized with severe laboratory-confirmed influenza during the 2017–2018 season in Catalonia. An observational epidemiological case-to-case study was carried out. Reported cases of severe laboratory-confirmed influenza requiring hospitalization in 2017–2018 influenza season were included. Mixed-effects regression analysis was used to estimate the factors associated with ICU admission and death. A total of 1306 cases of hospitalized severe influenza cases were included, of whom 175 (13.4%) died and 217 (16.6%) were ICU admitted. Age 65–74 years and ≥ 75 years and having ≥ 2 comorbidities were positively associated with death (aOR 3.19; 95%CI 1.19–8.50, aOR 6.95, 95%CI 2.76–1.80 and aOR 1.99; 95%CI 1.12–3.52, respectively). Neuraminidase inhibitor treatment and pneumonia were negatively associated with death. The 65–74 years and ≥ 75 years age groups were negatively associated with ICU admission (aOR 0.41; 95%CI 0.23–0.74 and aOR 0.30; 95%CI 0.17–0.53, respectively). A factor positively associated with ICU admission was neuraminidase inhibitor treatment. Our results support the need to investigate the worst outcomes of hospitalized severe cases, distinguishing between death and ICU admission.

Comparison between Patients Hospitalized with Influenza and COVID-19 at a Tertiary Care Center

BACKGROUND

Widespread reports suggest the characteristics and disease course of coronavirus disease 2019 (COVID-19) and influenza differ, yet detailed comparisons of their clinical manifestations are lacking.

OBJECTIVE

Comparison of the epidemiology and clinical characteristics of COVID-19 patients during the pandemic with those of influenza patients in previous influenza seasons at the same hospital DESIGN: Admission rates, clinical measurements, and clinical outcomes from confirmed COVID-19 cases between March 1 and April 30, 2020, were compared with those from confirmed influenza cases in the previous five influenza seasons (8 months each) beginning September 1, 2014.

SETTING

Large tertiary care teaching hospital in Boston, MA PARTICIPANTS: Laboratory-confirmed COVID-19 and influenza inpatients MEASUREMENTS: Patient demographics and medical history, mortality, incidence and duration of mechanical ventilation, incidences of vasopressor support and renal replacement therapy, and hospital and intensive care admissions.

RESULTS

Data was abstracted from medical records of 1052 influenza patients and 582 COVID-19 patients. An average of 210 hospital admissions for influenza occurred per 8-month season compared to 582 COVID-19 admissions over 2 months. The median weekly number of COVID-19 patients requiring mechanical ventilation was 17 (IQR: 4, 34) compared to a weekly median of 1 (IQR: 0, 2) influenza patient (p=0.001). COVID-19 patients were significantly more likely to require mechanical ventilation (31% vs 8%) and had significantly higher mortality (20% vs. 3%; p<0.001 for all). Relatively more COVID-19 patients on mechanical ventilation lacked pre-existing conditions compared with mechanically ventilated influenza patients (25% vs 4%, p<0.001). Pneumonia/ARDS secondary to the virus was the predominant cause of mechanical ventilation in COVID-19 patients (94%) as opposed to influenza (56%).

LIMITATION

This is a single-center study which could limit generalization.

CONCLUSION

COVID-19 resulted in more weekly hospitalizations, higher morbidity, and higher mortality than influenza at the same hospital.

SARS-CoV-2 infections in children and young people

Though recent reports link SARS-CoV-2 infections with hyper-inflammatory states in children, most children experience no/mild symptoms, and hospitalization and mortality rates are low in the age group. As symptoms are usually mild and seroconversion occurs at low frequencies, it remains unclear whether children significantly contribute to community transmission. Several hypotheses try to explain age-related differences in disease presentation and severity. Possible reasons for milder presentations in children as compared to adults include frequent contact to seasonal coronaviruses, presence of cross-reactive antibodies, and/or co-clearance with other viruses. Increased expression of ACE2 in young people may facilitate virus infection, while limiting inflammation and reducing the risk of severe disease. Further potential factors include recent vaccinations and a more diverse memory T cell repertoire. This manuscript reviews age-related host factors that may protect children from COVID-19 and complications associated, and addresses the confusion around seropositivity and immunity.