Seasonal influenza-associated intensive care unit admission and death in tropical Singapore, 2011-2015

Long-term sequelae post-hospitalization for respiratory syncytial virus vs. Omicron SARS-CoV-2 or influenza in adults and children: a retrospective cohort study

OBJECTIVES

Risk of long-term sequelae after COVID-19 hospitalization is well documented in adults and children; however, less is known about long-term sequelae after hospitalization for other respiratory viral infections (RVIs), such as respiratory syncytial virus (RSV). We sought to compare long-term sequelae after RSV hospitalization, contrasted against Omicron COVID-19 and influenza, in children and adults.

METHODS

This retrospective population-based cohort study in Singapore included all hospitalizations for RSV/influenza from 1 January 2017 to 3 September 2023, and all COVID-19 hospitalizations after Omicron emergence (1 January 2022-3 September 2023). Risks of new-incident diagnoses/symptoms 31-300 days following (a) RSV vs. COVID-19 hospitalization; (b) RSV vs. influenza hospitalization, across multiple organ systems, were estimated using Cox regression, adjusted for between-group sociodemographic and clinical differences using overlap weighting.

RESULTS

24 340 paediatric RVI hospitalizations (RSV = 8640; influenza = 9400; COVID-19 = 6300) and 82 635 adult RVI hospitalizations (RSV = 1553; influenza = 10 454; COVID-19 = 70 628) were included. In children, post-RSV hospitalization, higher risk and excess burden (EB) per 1000 individuals of any overall new-incident diagnosis were observed when contrasted against COVID-19/influenza (COVID-19: adjusted hazard ratio [aHR] = 1.63 [95% CI: 1.24-2.14], EB = 9.83 [95% CI: 5.26-14.41]; influenza: aHR = 1.76 [95% CI: 1.37-2.28], EB = 10.91 [95% CI: 6.78-15.04]); risks of respiratory sequelae predominated. In adults, though there was no significant difference in overall risk of post-acute sequelae between RSV and COVID-19/influenza, elevated risk of cardiovascular symptoms (aHR = 1.58 [95% CI: 1.13-2.22]) and other neurological disorders (aHR = 1.92 [95% CI: 1.31-2.80]) was observed in RSV hospitalizations vs. COVID-19.

DISCUSSION

Although risks of predominantly respiratory sequelae were elevated post-RSV hospitalization in children vs. COVID-19 or influenza, higher risk of extra-pulmonary sequelae (cardiovascular/neurological complications) was observed post-RSV hospitalization vs. COVID-19 in adults. Elevated risks at extremes of age highlight the importance of RSV vaccination in these vulnerable groups.

Whole-genome analysis of circulating influenza A virus (H3N2) strains in Shanghai, China from 2005 to 2023

Seasonal influenza A virus subtype H3N2 (A/H3N2) circulates globally and has been linked to higher hospitalization rates and summer outbreaks in temperate regions. Here, A/H3N2 circulation in Shanghai, China was systematically studied using data and materials generated by the Shanghai influenza surveillance network from 2005 to 2023. Time-series analysis of incidence and subtyping data showed that A/H3N2 co-circulated with other (sub)types and dominated in multiple seasonal influenza peaks, preferentially in summer. Whole genomes of 528 representative strains were sequenced, and spatiotemporal phylodynamic analysis using these and GISAID-archived sequences demonstrated that in the years before the COVID-19 pandemic, phylogenetically similar strains were circulating locally and elsewhere. However, clade 1a.1 (within 3C.2a.1b.2a), circulated in and only in Shanghai and domestically in 2022, while the sibling clade 2 predominated in other regions. Interestingly, clade 1a.1 was swiftly and completely replaced by clade 2, mostly 2a.3a.1, at the start of 2023. In hemagglutination inhibition and neutralization assays, sera from healthy donors collected in 2022 displayed higher or similar reactivity against 2a.3a.1 compared to 1a.1. By contrast, transcription and replication competence of 2a.3a.1 in MDCK cells was higher than 1a.1. These results indicated that instead of antigenicity differences enabling evasion of pre-existing immunity, higher replicative capability more likely contributed to 2a.3a.1 viruses achieving dominance in China. In addition to summarizing patterns of A/H3N2 local circulation in Shanghai, this work revealed an unusual episode in A/H3N2 global circulation and evolution dynamics in connection to the COVID-19 pandemic and explored possible mechanistic explanations.

Covid 19 death analysis in Colombia

Introduction

This article shows an analysis of the evolution up until date (May 4-2021), of official coronavirus cases statistics (CC) and the total number of deaths (TND) due to SARS-CoV-2 in Colombia. Additionally, said information is shown in correlation to other variables such as Case Fatality Rate (CFR), age range of persons, their typical reported co-morbidities and the cities where there has been highest concentration of cases.

Materials and Methods

From March 16 2020 until today, information regarding the daily number of new confirmed cases (DNC) and daily confirmed deaths (DD) was registered in a database with the purpose of estimating the evolution of CC, TND and CFR. The age of deceased was also registered, as well as their gender, prior co-morbidities and city of death. The evolution of TND with the time of other countries were compared to that of Colombia. A mathematical equation that represents the epidemiological curve of TND evolution of different countries across time was defined.

Results

In Colombia, the average age of people who die due to COVID-19 is of 69.5±14.7 years (median and mode of 71 and 80 years, respectively), and the virus is less lethal amongst a population under the age of 40. The greater part of deaths have taken place in people with prior co-morbidities and of the male gender.

Conclusion

Most of the persons that have deceased are those of senior age, mainly with prior co-morbidities, and predominantly of male gender. Epidemiological peaks of COVID-19 are consistent with the rainy and winter seasons, and with the traditional epidemiological peaks of flu or influenza.

The impact of obesity on seasonal influenza: a single-center, retrospective study conducted in Israel

Obesity is associated with an increased susceptibility to infections. Several studies have reported adverse clinical outcomes of influenza among obese individuals. Our aim was to examine the association between obesity and the clinical outcomes of hospitalized adult patients ill with seasonal influenza. Consecutive hospitalized adult patients between 10/2017 and 4/2018 with laboratory confirmed influenza A and B were divided into an obese group (body mass index (BMI) ≥ 30 kg/m2) and controls. The primary outcome was a composite endpoint of 30-day all-cause mortality, vasopressor use, mechanical ventilation, ICU admission, and severe influenza complication (myocarditis and encephalitis). Secondary outcomes encompassed all the components of the primary outcome, 90-day all-cause mortality, occurrence of pneumonia, length of hospital stay, and 90-day readmission rates. The study comprised 512 hospitalized adults diagnosed with laboratory-confirmed influenza A (195/512) and B (317/512). Within this group, 17% (86/512) were classified obese; the remaining 83% (426/512) were controls. Results of the composite outcome (7/85, 8% vs. 45/422, 11%; p=0.5) and the crude 30-day all-cause mortality rate (5/86, 6% vs. 34/426, 8%, p=0.5) were similar between the two groups. The multivariate analysis demonstrated that obesity was not a significant risk factor for influenza adverse events (OR=1.3, CI 95% 0.3-3.3; p=0.5), whereas advanced age, chronic kidney disease, and hypoalbuminemia were significant risk factors (OR=1.03, OR=2.7, and OR=5.4, respectively). Obesity was not associated with influenza-related morbidity and mortality among the hospitalized adults during the 2017-2018 influenza season. Further studies researching different influenza seasons are essential.

Respiratory microbes detected in hospitalized adults with acute respiratory infections: associations between influenza A(H1N1)pdm09 virus and intensive care unit admission or fatal outcome in Vietnam (2015-2017)

Background

Acute respiratory tract infection (ARI) is a leading cause of hospitalization, morbidity, and mortality worldwide. Respiratory microbes that were simultaneously detected in the respiratory tracts of hospitalized adult ARI patients were investigated. Associations between influenza A(H1N1)pdm09 virus (H1N1pdm) detection and intensive care unit (ICU) admission or fatal outcome were determined.

Methods

This prospective observational study was conducted between September 2015 and June 2017 at Bach Mai Hospital, Hanoi, Vietnam. Inclusion criteria were hospitalized patients aged ≥15 years; one or more of symptoms including shortness of breath, sore throat, runny nose, headache, and muscle pain/arthralgia in addition to cough and fever > 37.5 °C; and ≤ 10 days from the onset of symptoms. Twenty-two viruses, 11 bacteria, and one fungus in airway specimens were examined using a commercial multiplex real-time PCR assay. Associations between H1N1pdm detection and ICU admission or fatal outcome were investigated by univariate and multivariate logistic regression analyses.

Results

The total of 269 patients (57.6% male; median age, 51 years) included 69 ICU patients. One or more microbes were detected in the airways of 214 patients (79.6%). Single and multiple microbes were detected in 41.3 and 38.3% of patients, respectively. Influenza A(H3N2) virus was the most frequently detected (35 cases; 13.0%), followed by H1N1pdm (29 cases; 10.8%). Hematological disease was associated with ICU admission (p < 0.001) and fatal outcomes (p < 0.001) using the corrected significance level (p = 0.0033). Sex, age, duration from onset to sampling, or number of detected microbes were not significantly associated with ICU admission or fatal outcomes. H1N1pdm detection was associated with ICU admission (odds ratio [OR] 3.911; 95% confidence interval [CI] 1.671–9.154) and fatal outcome (OR 5.496; 95% CI 1.814–16.653) after adjusting for the confounding factors of comorbidities, bacteria/Pneumocystis jirovecii co-detection, and age.

Conclusions

H1N1pdm was associated with severe morbidity and death in adult patients hospitalized with respiratory symptoms. The diagnosis of subtype of influenza virus may be epidemiologically important.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05988-x.

Effect of antiviral treatment in older patients hospitalized with confirmed influenza

Seasonal influenza causes significant morbidity and mortality in people aged ≥65 years. Antiviral treatment can reduce complications and disease severity. The objective of this study was to investigate the effect of antiviral treatment in patients aged ≥65 years hospitalized with confirmed influenza in preventing intensive care unit (ICU) admission or death. A retrospective cohort study was carried out in 20 hospitals from seven Spanish regions during 2013-2015 in patients aged ≥65 years. Hospitalized cases of laboratory-confirmed influenza were selected. To assess the association between antiviral treatment and ICU admission or death, the adjusted odds ratios (aOR) and their 95% confidence intervals (CI) were calculated using multivariate logistic regression. We included 715 hospitalized patients, of whom 640 (87.9%) received antiviral treatment, 77 (10.8%) required ICU admission and 66 (9.2%) died. In the 64-74 years age group, receipt of antiviral treatment ≤48 h (aOR 0.20; 95% CI 0.04-0.89), 3-4 days (aOR 0.23; 95% CI 0.05-0.92) and 5-7 days (aOR 0.24; 95% CI 0.03-0.91) after clinical symptom onset was associated with reduced mortality. Receipt of treatment >7 days after symptom onset was not associated with reduced mortality. No association of antiviral treatment with reduced mortality was observed in the >74 years age group or with the prevention of ICU admission in any age group. Antiviral treatment had a protective effect in avoiding death in patients aged 65-74 years hospitalized due to influenza when administered ≤48 h after symptom onset and when no more than 7 days had elapsed.

Influenza A-associated severe pneumonia in hospitalized patients: Risk factors and NAI treatments

OBJECTIVE

The risk factors and the impact of NAI treatments in patients with severe influenza A-associated pneumonia remain unclear.

METHODS

A multicenter, retrospective, observational study was conducted in Zhejiang, China during a severe influenza epidemic in August 2017-May 2018. Clinical records of patients (>14 y) hospitalized with laboratory-confirmed influenza A virus infection and who developed severe pneumonia were compared to those with mild-to-moderate pneumonia. Risk factors related to pneumonia severity and effects of NAI treatments (monotherapy and combination of peramivir and oseltamivir) were analyzed.

RESULTS

202 patients with influenza A-associated severe pneumonia were enrolled, of whom 84 (41.6%) had died. Male gender (OR = 1.782; 95% CI: 1.089-2.917; P = 0.022), chronic pulmonary disease (OR = 2.581; 95% CI: 1.447-4.603; P = 0.001) and diabetes mellitus (OR = 2.042; 95% CI: 1.135-3.673; P = 0.017) were risk factors related to influenza A pneumonia severity. In cox proportional hazards model, severe pneumonia patients treated with double dose oseltamivir (300mg/d) had a better survival rate compared to those receiving a single dose (150 mg/d) (HR = 0.475; 95%CI: 0.254-0.887; P = 0.019). However, different doses of peramivir (300 mg/d vs. 600 mg/d) and combination therapy (oseltamivir-peramivir vs. monotherapy) showed no differences in 60-day mortality (P = 0.392 and P = 0.658, respectively).

CONCLUSIONS

Patients with male gender, chronic pulmonary disease, or diabetes mellitus were at high risk of developing severe pneumonia after influenza A infection. Double dose oseltamivir might be considered in treating influenza A-associated severe pneumonia.

Myocardial injury determination improves risk stratification and predicts mortality in COVID-19 patients

BACKGROUND

Despite being associated with worse prognosis in patients with COVID-19, systematic determination of myocardial injury is not recommended. The aim of the study was to study the effect of myocardial injury assessment on risk stratification of COVID-19 patients.

METHODS

Seven hundred seven consecutive adult patients admitted to a large tertiary hospital with confirmed COVID-19 were included. Demographic data, comorbidities, laboratory results and clinical outcomes were recorded. Charlson comorbidity index (CCI) was calculated in order to quantify the degree of comorbidities. Independent association of cardiac troponin I (cTnI) increase with outcomes was evaluated by multivariate regression analyses and area under curve. In addition, propensity-score matching was performed to assemble a cohort of patients with similar baseline characteristics.

RESULTS

In the matched cohort (mean age 66.76 ± 15.7 years, 37.3% females), cTnI increase above the upper limit was present in 20.9% of the population and was associated with worse clinical outcomes, including all-cause mortality within 30 days (45.1% vs. 23.2%; p = 0.005). The addition of cTnI to a multivariate prediction model showed a significant improvement in the area under the time-dependent receiver operating characteristic curve (0.775 vs. 0.756, DC-statistic = 0.019; 95% confidence interval 0.001-0.037). Use of renin-angiotensin-aldosterone system inhibitors was not associated with mortality after adjusting by baseline risk factors.

CONCLUSIONS

Myocardial injury is independently associated with adverse outcomes irrespective of baseline comorbidities and its addition to multivariate regression models significantly improves their performance in predicting mortality. The determination of myocardial injury biomarkers on hospital admission and its combination with CCI can classify patients in three risk groups (high, intermediate and low) with a clearly distinct 30-day mortality.