Clinical Characteristics of Influenza in Season 2017/2018 in a German Emergency Department: A Retrospective Analysis

Understanding the Global Burden of Influenza in Adults Aged 18-64 years: A Systematic Literature Review from 2012 to 2022

INTRODUCTION

Adults aged 18-64 years comprise most of the working population, meaning that influenza infection can be disruptive, causing prolonged absence from the workplace, and reduced productivity and the ability to care for dependents. Influenza vaccine uptake is relatively low, even among the older adults in this population (i.e., aged 50-64 years), reflecting a lack of perceived need for vaccination. This systematic literature review (SLR) aimed to characterize the global burden of influenza in the 18-64 years population.

METHODS

An electronic database search was conducted and supplemented with conference and gray literature searches. Eligible studies described at least one of clinical, humanistic, or economic outcomes in adults aged 18-64 years and conducted across several global regions. Included studies were published in English, between January 1, 2012, and September 20, 2022.

RESULTS

A total of 40 publications were included, with clinical, humanistic, and economic outcomes reported in 39, 5, and 15, respectively. Risk of influenza-associated clinical outcomes were reported to increase with age among the 18-64 years population, including hospitalizations (Yamana et al. in Intern Med 60:3401-3408, 2021; Derqui et al. in Influenza Other Respir Viruses 16:862-872, 2022; Fuller et al. in Influenza Other Respir Viruses 16:265-275, 2022; Ortiz et al. in Crit Care Med 42:2325-2332, 2014; Yandrapalli et al. in Ann Transl Med 6:318, 2018; Zimmerman et al. in Influenza Other Respir Viruses 16:1133-1140, 2022). ICU admissions, mortality, ER/outpatient visits, and use of mechanical ventilation were recorded. Adults aged 18-64 years with underlying comorbidities were at higher risk of influenza-related hospitalizations, ICU admission, and mortality than otherwise healthy individuals. Length of hospital stay increased with age, although a lack of stratification across other economic outcomes prevented identification of further trends across age groups.

CONCLUSIONS

High levels of hospitalization and outpatient visits demonstrated a clinical influenza-associated burden on patients and healthcare systems, which is exacerbated by comorbidities. Considering the size and breadth of the general population aged 18-64 years, the limited humanistic and economic findings of this SLR likely reflect an underreported burden. Greater investigation into indirect costs and prolonged absenteeism associated with influenza infection is required to fully understand the economic burden in this population.

Symptomatic Differences between Influenza A/H3N2 and A/H1N1 in Korea

BACKGROUND

Limited understanding exists regarding clinical distinctions between influenza A/H3N2 and A/H1N1 subtypes, particularly in primary health care. We conducted a comparative analysis of symptomatic characteristics of influenza subtypes in Korea. This retrospective study analyzed medical records of patients who presented with positive test results for influenza-like illness (rapid influenza diagnostic test; RIDT) during the H3N2-dominant 2016-2017 and H1N1-dominant 2018-2019 seasons. Symptomatic manifestations, contact history, vaccination history, and clinical course were analyzed between the two seasons. The most frequent symptom in the RIDT-positive patients was fever (80.1% and 79.1%, respectively). The average body temperature was higher, and the number of patients with high fever was greater in the H3N2-dominant season than in the H1N1-dominant season (p < 0.001). Conversely, other symptoms, such as myalgia, cough, and sore throat, were significantly more common in the H1N1-dominant season than in the H3N2-dominant season (p < 0.001). Antiviral drugs were prescribed to most febrile RIDT-positive patients (82.2% and 81.3%, respectively, p = 0.516). Analyzing primary care data revealed different clinical manifestations according to the subtype. Therefore, physicians should consider these variable hallmarks and employ tailored therapeutic strategies to reduce the complication rate.

COVID-19 infection following influenza vaccine injection and its complications among nurses working in educational-medical hospitals of Ardabil in 2020

Objectives

Health care workers are one of the groups at risk of influenza. Currently, influenza vaccination is very important more than ever before. Influenza is evolutionarily similar to SARS-CoV-2, and they have some common epitopes and mechanisms. Thus reducing the severity of COVID-19 disease by influenza vaccination seems possible. Therefore, the aim of this study is to investigate the relationship between influenza vaccination and COVID-19 infection among clinical nurses.

Methodology

The present study is a prospective analysis of nurses working in educational-medical hospitals of Ardabil. In this study, two groups of nurses were considered as case and control groups. The collected data were analyzed using SPSS software and descriptive (mean, standard deviation and frequency) and analytical (Chi-square) tests.

Results

A total of 279 individuals were included in the study according to the research criteria. The maximum duration of the disease was one week in the control group and four weeks in the case group. Chi-square test showed that there was a significant difference in terms of disease duration between the two groups (P = 0.000). Chi-square test showed that there was a statistically significant difference in terms of disease treatment between the two groups (P = 0.000).

Conclusion

Influenza vaccine reduces the incidence of COVID-19 and reduces the need for hospitalization in patients with this disease. However, due to the positive effects of influenza vaccine on COVID-19 and its low cost, it is recommended to inject influenza vaccine more than before.

COVID-19-induced headache in Boston and the vicinity

Headache is a common neurological symptom of Coronavirus disease 2019 (COVID-19) patients. However, the prevalence, comorbidities, and ethnic susceptibilities of COVID-19-induced headaches are not well-defined.

We performed a retrospective chart review of patients who tested positive for SARS-CoV2 by reverse transcriptase-polymerase chain reaction (RT-PCR) in March and April 2020 at Massachusetts General Hospital, Boston, Massachusetts, USA.

In the study, we identified 450 patients, 202 (44.9%) male, and 248 (55.1%) female, who tested positive for COVID-19. Headache is a significant painful symptom affecting 26% of patients. Female predominance is determined in sore throat, nasal congestion, hypogeusia, headache, and ear pain. In contrast, pneumonia and inpatient hospitalization were more prevalent in males. Younger patients (< 50) were more likely to develop sore throat, fatigue, anosmia, hypogeusia, ear pain, myalgia /arthralgia, and headache. In contrast, older (> 50) patients were prone to develop pneumonia and required hospitalization.

Ethnic subgroup analysis suggests Hispanic patients were prone to headaches, nausea/vomiting, nasal congestion, fever, fatigue, anosmia, and myalgia/arthralgia compared to non-Hispanics. Headache risk factors include nausea/vomiting, sore throat, nasal congestion, fever, cough, fatigue, anosmia, hypogeusia, dizziness, ear pain, eye pain, and myalgia/arthralgia.

Our study demonstrates regional gender, age, and ethnic variabilities in COVID symptomatology in Boston and the vicinity. It identifies mild viral, painful, and neurological symptoms are positive predictors of headache development in COVID-19.

A strict mask policy for hospital staff effectively prevents from nosocomial influenza infections and mortality: monocentric data from five consecutive influenza seasons

BACKGROUND

Influenza infections acquired in hospital show increased mortality, especially in elderly patients with risk factors. Nevertheless, vaccination rates are low among both high-risk patients and healthcare workers (HCW). To more effectively prevent influenza infections in the hospital during the influenza season, we introduced a strict mouth-nose protection (MNP) requirement for all staff throughout the shift on the affected wards as an intervention and studied its effect on nosocomial infection rates.

METHODOLOGY

The present data were obtained in a retrospective, monocentric analysis over a period of four consecutive influenza seasons from 2015 - 2019. MNP for all staff during the whole shift as an intervention was introduced at 2017 and for the following seasons if at least three flu patients were in the ward at the same time. Data from hospitalised influenza patients before and after intervention were compared with regard to nosocomial incidences and mortality.

RESULTS

In the years with strict mandatory MNP (2017 - 2019), the nosocomial influenza incidence fell nearly 50 % (OR 0.40, 95%CI 0.28 - 0.56, p < 0.001) accompanied by a significant reduction in nosocomial mortality by 85% (OR 0.15, 95%CI 0.02 - 0.70, p = 0.007). The infectious pressure indicated by influenza incidences and patient days at risk were comparable before and after intervention, as was the low rate of vaccine uptake by nurses.

CONCLUSION

From our data, we conclude that mandatory MNP for HCW effectively protect patients from nosocomial influenza infections and mortality.

Point-of-care testing for influenza in a university emergency department: A prospective study

BACKGROUND

Seasonal influenza is a burden for emergency departments (ED). The aim of this study was to investigate whether point-of-care (POC) PCR testing can be used to reduce staff sick days and improve diagnostic and therapeutic procedures.

OBJECTIVES

The aim of this study was to investigate whether point-of-care (POC) PCR testing can be used to reduce staff sick days and improve diagnostic and therapeutic procedures.

METHODS

Using a cross-over design, the cobas® Liat® Influenza A/B POC PCR test (Liat) was compared with standard clinical practice during the 2019/2020 influenza season. All adult patients (aged ≥ 18 years) with fever (≥38°C) and respiratory symptoms were included. Primary end points were the prevalence of influenza infections in the ED and staff sick days. Secondary end points were frequency of antiviral and antibacterial therapy, time between admission and test result or treatment initiation, patient disposition, ED length of stay (LOS), and for inpatients mortality and LOS. Nurses were interviewed about handling and integration of POC testing. The occurrence of SARS-CoV-2 infections coincided with the second half of the study.

RESULTS

A total of 828 patients were enrolled in the study. All 375 patients of the intervention group were tested with Liat, and 103 patients of them (27.6%) tested positive. During the intervention period, staff sick days were reduced by 34.4% (P = .023). Significantly, more patients in the intervention group received antiviral therapy with neuraminidase inhibitors (7.2% vs 3.8%, P = .028) and tested patients received antibiotics more frequently (40.0% vs 31.6%, P = .033). Patients with POC test were transferred to external hospitals significantly more often (5.6% vs 1.3%, P = .01).

CONCLUSION

We conclude that POC testing for influenza is useful in the ED, especially if it is heavily frequented by patients with respiratory symptoms.

A CT radiomics analysis of COVID-19-related ground-glass opacities and consolidation: Is it valuable in a differential diagnosis with other atypical pneumonias?

PURPOSE

To evaluate the discrimination of parenchymal lesions between COVID-19 and other atypical pneumonia (AP) by using only radiomics features.

METHODS

In this retrospective study, 301 pneumonic lesions (150 ground-glass opacity [GGO], 52 crazy paving [CP], 99 consolidation) obtained from nonenhanced thorax CT scans of 74 AP (46 male and 28 female; 48.25±13.67 years) and 60 COVID-19 (39 male and 21 female; 48.01±20.38 years) patients were segmented manually by two independent radiologists, and Location, Size, Shape, and First- and Second-order radiomics features were calculated.

RESULTS

Multiple parameters showed significant differences between AP and COVID-19-related GGOs and consolidations, although only the Range parameter was significantly different for CPs. Models developed by using the Bayesian information criterion (BIC) for the whole group of GGO and consolidation lesions predicted COVID-19 consolidation and AP GGO lesions with low accuracy (46.1% and 60.8%, respectively). Thus, instead of subjective classification, lesions were reclassified according to their skewness into positive skewness group (PSG, 78 AP and 71 COVID-19 lesions) and negative skewness group (NSG, 56 AP and 44 COVID-19 lesions), and group-specific models were created. The best AUC, accuracy, sensitivity, and specificity were respectively 0.774, 75.8%, 74.6%, and 76.9% among the PSG models and 0.907, 83%, 79.5%, and 85.7% for the NSG models. The best PSG model was also better at predicting NSG lesions smaller than 3 mL. Using an algorithm, 80% of COVID-19 and 81.1% of AP patients were correctly predicted.

CONCLUSION

During periods of increasing AP, radiomics parameters may provide valuable data for the differential diagnosis of COVID-19.

Detection of influenza virus in air samples of patient rooms

BACKGROUND

Understanding the transmission and dispersal of influenza virus and respiratory syncytial virus (RSV) via aerosols is essential for the development of preventative measures in hospital environments and healthcare facilities.

METHODS

During the 2017-2018 influenza season, patients with confirmed influenza or RSV infections were enrolled. Room air samples were collected close (0.30 m) to and distant (2.20 m) from patients' heads. Real-time polymerase chain reaction was used to detect and quantify viral particles in the air samples. The plaque assay was used to determine the infectiousness of the detected viruses.

FINDINGS

Fifty-one air samples were collected from the rooms of 29 patients with laboratory-confirmed influenza; 51% of the samples tested positive for influenza A virus (IAV). Among the IAV-positive patients, 65% were emitters (had at least one positive air sample), reflecting a higher risk of nosocomial transmission compared with non-emitters. The majority (61.5%) of the IAV-positive air samples were collected 0.3 m from a patient's head, while the remaining IAV-positive air samples were collected 2.2 m from a patient's head. The positivity rate of IAV in air samples was influenced by distance from the patient's head and day of sample collection after hospital admission. Only three patients with RSV infection were recruited and none of them were emitters.

CONCLUSION

Influenza virus can be aerosolized beyond 1 m in patient rooms, which is the distance considered to be safe by infection control practices. Further investigations are needed to determine the extent of infectivity of aerosolized virus particles.

Influenza-associated in-hospital mortality during the 2017/2018 influenza season: a retrospective multicentre cohort study in central Germany

The aim of this retrospective cohort study at eight hospitals in Germany was to specify influenza-associated in-hospital mortality during the 2017/2018 flu season, which was the strongest in Germany in the past 30 years. A total of 1560 patients were included in the study. Overall, in-hospital mortality was 6.7% (n = 103), in patients treated in the intensive care unit (n = 161) mortality was 22.4%. The proportion of deceased patients per hospital was between 0% and 7.0%. Influenza was the immediate cause of death in 82.8% (n = 82) of the decedents.

Systematically comparing COVID-19 with the 2009 influenza pandemic for hospitalized patients

OBJECTIVES

This study aimed to comprehensively compare the clinical features of hospitalized COVID-19 patients with hospitalized 2009 influenza pandemic patients.

METHODS

Medline, Embase, Web of Science, Cochrane CENTRAL, and Google scholar were systematically searched to identify studies related to COVID-19 and the 2009 influenza pandemic. The pooled incidence rates of clinical features were estimated using the DerSimonian-Laird random-effects model with the Freeman-Tukey double arcsine transformation method.

RESULTS

The incidence rates of fever, cough, shortness of breath, sore throat, rhinorrhea, myalgia/muscle pain, or vomiting were found to be significantly higher in influenza patients when compared with COVID-19 patients. The incidence rates of comorbidities, including cardiovascular disease/hypertension and diabetes, were significantly higher in COVID-19 compared with influenza patients. In contrast, comorbidities such as asthma, chronic obstructive pulmonary disease, and immunocompromised conditions were significantly more common in influenza compared with COVID-19 patients. Unexpectedly, the estimated rates of intensive care unit admission, treatment with extracorporeal membrane oxygenation, treatment with antibiotics, and fatality were comparable between hospitalized COVID-19 and 2009 influenza pandemic patients.

CONCLUSIONS

This study comprehensively estimated the differences and similarities of the clinical features and burdens of hospitalized COVID-19 and 2009 influenza pandemic patients. This information will be important to better understand the current COVID-19 pandemic.

Detection of influenza virus in air samples of patient rooms

BACKGROUND

Understanding the transmission and dispersal of influenza virus and respiratory syncytial virus (RSV) via aerosols is essential for the development of preventative measures in hospital environments and healthcare facilities.

METHODS

During the 2017-2018 influenza season, patients with confirmed influenza or RSV infections were enrolled. Room air samples were collected close (0.30 m) to and distant (2.20 m) from patients' heads. Real-time polymerase chain reaction was used to detect and quantify viral particles in the air samples. The plaque assay was used to determine the infectiousness of the detected viruses.

FINDINGS

Fifty-one air samples were collected from the rooms of 29 patients with laboratory-confirmed influenza; 51% of the samples tested positive for influenza A virus (IAV). Among the IAV-positive patients, 65% were emitters (had at least one positive air sample), reflecting a higher risk of nosocomial transmission compared with non-emitters. The majority (61.5%) of the IAV-positive air samples were collected 0.3 m from a patient's head, while the remaining IAV-positive air samples were collected 2.2 m from a patient's head. The positivity rate of IAV in air samples was influenced by distance from the patient's head and day of sample collection after hospital admission. Only three patients with RSV infection were recruited and none of them were emitters.

CONCLUSION

Influenza virus can be aerosolized beyond 1 m in patient rooms, which is the distance considered to be safe by infection control practices. Further investigations are needed to determine the extent of infectivity of aerosolized virus particles.

Headache in Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Narrative Review

OBJECTIVE

To summarize available literature regarding headache as a manifestation of coronaviruses and to describe potential underlying mechanisms.

REVIEW METHODS

References for this review were identified by searches within PubMed without any date restrictions. The search terms used were coronavirus disease 2019 (COVID-19) clinical manifestation, COVID-19 epidemiology, neurologic findings in COVID-19, headache in COVID-19, neurologic manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and headache in SARS-CoV-2.

RESULTS

Headache is one of the most common neurologic complaints in patients with SARS-CoV-2. While the pathophysiological connection between headache and SARS-CoV-2 is unclear, inflammatory mechanisms may play a key role. One of the mechanisms cited in the literature of migraine and other headache disorders is the activation of nociceptive sensory neurons by cytokines and chemokines. A similar mechanism has been reported in SARS-CoV-2 with the release of cytokines and chemokines by macrophages throughout the course of infection. Other mechanisms for headache in SARS-CoV-2 include (1) viral neuroinvasion as seen with viral encephalitis; (2) hypoxemia due to the well-described pulmonary manifestations of the disease; and (3) thrombosis secondary to COVID-19 induced hypercoagulable states.

CONCLUSION

According to the Centers for Disease Control, common symptoms of human coronavirus include fever, cough, runny nose, sore throat, and headache. In the case of SARS-CoV-2, there are limited reports about headaches, one of the most common clinical manifestations. There are currently no studies that focus specifically on headache among patients with SARS-CoV-2 infection.

Epidemiological and clinical characteristics of 333 confirmed cases with coronavirus disease 2019 in Shanghai, China

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease first identified in Wuhan City, Hubei Province, China. As of 19 February 2020, there had been 333 confirmed cases reported in Shanghai, China. This study elaborates on the epidemiological and clinical characteristics of COVID-19 based on a descriptive study of the 333 patients infected with COVID-19 in Shanghai for the purpose of probing into this new disease and providing reference. Among the 333 confirmed cases in Shanghai, 172 (51.7%) were males and 161 (48.3%) were females, with a median age of 50 years. 299 (89.8%) cases presented mild symptoms. 139 (41.7%) and 111 (33.3%) cases were infected in Wuhan and Shanghai, respectively. 148 (44.4%) cases once had contact with confirmed cases before onset, while 103 (30.9%) cases had never contacted confirmed cases but they had a sojourn history in Wuhan. The onset date of the first case in Shanghai was 28 December, with the peak appearing on 27 January. The median incubation period of COVID-19 was estimated to be 7.2 days. 207 (62.2%) cases had fever symptoms at the onset, whereas 273 (82.0%) cases experienced fever before hospitalization. 56 (18.6%) adults experienced a decrease in white blood cell and 84 (42.9%) had increased C-reactive protein after onset. Elderly, male and heart disease history were risk factors for severe or critical pneumonia. These findings suggest that most cases experienced fever symptoms and had mild pneumonia. Strengthening the health management of elderly men, especially those with underlying diseases, may help reduce the incidence of severe and critical pneumonia. Time intervals from onset to visit, hospitalization and diagnosis confirmed were all shortened after Shanghai's first-level public health emergency response. Shanghai's experience proves that COVID-19 can be controlled well in megacities.