Epidemiology of influenza from 2017 to 2022 in a national children's regional medical center

BACKGROUND

To examine the changes in influenza types (A/B), including influenza A subtypes (A(H1N1) / A(H3N2)) and influenza B lineages (B/Victoria and B/Yamagata) in children in Hangzhou City, China.

METHODS

This retrospective study was conducted in a national children's regional medical center, using data from children screened for influenza between January 2017 and December 2022.

RESULTS

6775 patients (3 months to 14 years, 54.16% boys) were identified to have influenza-like symptoms. Among all patients, 905 (13.36%) patients were positive for the influenza virus. The number of patients positive for influenza was 222 (21.31%), 129 (12.40%), 270 (25.71%), 59 (5.15%), 37 (3.03%), and 188 (14.72%) from 2017 to 2022, respectively. The prevalence of influenza was higher in the more than 6 years old (n = 332, 23.23%) and 3-6 years old (n = 397, 13.18%) than in the under 3 years old (n = 176, 7.54%) groups, indicating that the influenza infection might increase with age. A/H3N2 infection was highest in the under 3 years old and 3-6 years old age groups while B/Victoria infection was highest in the more than 6 years old age group. The positive rates of influenza A (7.41% vs. 7.22%, P = 0.767) and B (5.47% vs. 5.94%, P = 0.407) among boys and girls did not have much difference The seasonal characteristics showed that, among patients with influenza-like symptoms, winter and spring were the dominant flu season in Hangzhou. The most common virus subtypes were B/Victoria in the spring and A/H3N2 in other seasons. The influenza positive rates among different seasons were different, in winter it was higher compared with the other seasons except for 2021 and 2022, results also revealed that influenza A/H3N2 had a relatively high prevalence in summer.

CONCLUSIONS

The influenza viruses infection rate in 3 months to 14 years participants ranged from 3.03 to 25.7%, and the positive rate increased with age. No significant difference was observed in different sexes and subtypes of influenza. However, the relatively high prevalence of influenza A/H3N2 and high prevalence of all four subtypes indicate more attention to influenza infection should be paid in summer and winter.

Real-life antimicrobial therapy in hospitalized patients with COVID-19 (preliminary results and recommendations)

Objective. Development of local clinical protocols for antibacterial therapy of COVID-19-associated bacterial pneumonia in the therapeutic department of the city clinical hospital based on an analysis of the treatment process in patients with COVID-19-associated pneumonia. Materials and Methods. A retrospective analysis of 1382 cases of hospitalization in the therapeutic department of patients with COVID-19-associated pneumonia for the period from 2020 to 2021 was carried out. The structure of etiotropic therapy, the frequency and timing of microbiological studies of the biomaterial, the manifestations of the main markers of bacterial infection during dynamic monitoring of clinical and laboratory parameters in patients prescribed antibiotic therapy, as well as statistics of the stay of patients in the therapeutic department of the hospital were assessed. Based on the results obtained in the course of microbiological studies, an assessment was made of the microbial landscape of the lower respiratory tract of patients with an analysis of the sensitivity of strains of the leading microflora to a wide range of antibiotics. Results. The study found that the dominant flora in COVID-19-associated pneumonia in hospitalized patients was gram-negative bacteria – K. pneumoniae, P. aeruginosa and A. baumannii – their proportion was more than 50%. Among K. pneumoniae strains, 89.4% were ESBL producers, 63.5% of the strains were resistant to carbapenems, which with a high probability allows them to be considered carbapenemaseproducing strains. Among the strains of P. aeruginosa, the proportion of strains resistant to carbapenems and with a high degree of probability being strains – producers of carbapenemase was 41.1%. Among strains of Acinetobacter spp. these were 76.4%, and associated resistance to fluoroquinolones and aminoglycosides was also demonstrated. Gram-positive microorganisms were found in 34.3% of cases and were mainly represented by strains of S. aureus (74.9%), only 26.4% of strains of this pathogen were methicillin-resistant. Conclusions. Microbiological monitoring conducted in 2020–2021 revealed the presence, among the pathogens of viral-bacterial pneumonia, at an early stage of hospitalization, a significant proportion of gram-negative bacteria with resistance of the MDR and XDR types. Based on the obtained microbiological data, starting empirical schemes for antibacterial therapy of secondary viral and bacterial pneumonia, which complicated the course of a new coronavirus infection COVID-19 caused by the SARS-CoV-2 virus, were developed and proposed.

Antiviral Use in Canadian Children Hospitalized for Influenza

OBJECTIVES

Antivirals are recommended for children hospitalized with influenza but are underutilized. We describe antiviral prescribing during influenza admissions in Canadian pediatric centers and identify factors associated with antiviral use.

METHODS

We performed active surveillance for laboratory-confirmed influenza hospitalizations among children ≤16 years old at the 12 Canadian Immunization Monitoring Program Active hospitals, from 2010-2011 to 2018-2019. Logistic regression analyses were used to identify factors associated with antiviral use.

RESULTS

Among 7545 patients, 57.4% were male; median age was 3 years (interquartile range: 1.1-6.3). Overall, 41.3% received antiviral agents; 72.8% received antibiotics. Antiviral use varied across sites (range, 10.2% to 81.1%) and influenza season (range, 19.9% to 59.6%) and was more frequent in children with ≥1 chronic health condition (52.7% vs 36.7%; P < .001). On multivariable analysis, factors associated with antiviral use included older age (adjusted odds ratio [aOR] 1.04 [95% confidence interval (CI), 1.02-1.05]), more recent season (highest aOR 9.18 [95% CI, 6.70-12.57] for 2018-2019), admission during peak influenza period (aOR 1.37 [95% CI, 1.19-1.58]), availability of local treatment guideline (aOR 1.54 [95% CI, 1.17-2.02]), timing of laboratory confirmation (highest aOR 2.67 [95% CI, 1.97-3.61] for result available before admission), presence of chronic health conditions (highest aOR 4.81 [95% CI, 3.61-6.40] for cancer), radiographically confirmed pneumonia (aOR 1.39 [95% CI, 1.20-1.60]), antibiotic treatment (aOR 1.51 [95% CI, 1.30-1.76]), respiratory support (1.57 [95% CI, 1.19-2.08]), and ICU admission (aOR 3.62 [95% CI, 2.88-4.56]).

CONCLUSIONS

Influenza antiviral agents were underused in Canadian pediatric hospitals, including among children with high-risk chronic health conditions. Prescribing varied considerably across sites, increased over time, and was associated with patient and hospital-level characteristics. Multifaceted hospital-based interventions are warranted to strengthen adherence to influenza treatment guidelines and antimicrobial stewardship practices.

The Impact of Pneumonia on the Course and Outcome in Patients with Seasonal Influzenza

INTRODUCTION

Seasonal influenza, although often presented as a mild, self-limiting disease, is frequently accompanied by complications that lead to the development of a severe clinical presentation and a fatal outcome. The most common are respiratory complications, with secondary bacterial pneumonia being the leading cause.

AIM

The aim of this study is to determine the impact of pneumonia on the severity of the clinical presentation and outcome in patients with seasonal influenza.

MATERIALS AND METHODS

This research is comparatively group-based and has been conducted at the University Clinic for Infectious Diseases and Febrile Conditions during a three-year period. The analysis consists of 122 adult patients with clinically and laboratory-confirmed influenza. Based on the severity of the clinical picture, the patients are divided into two groups, severe (n=87) and mild (n=35) forms of the disease. The study included demographic, general data, clinical symptoms, and signs as well as complications.

RESULTS

Of 122 patients with seasonal influenza, complications were registered among 108(88.52%), with a significantly more frequent emergence among the group with severe influenza 93.1% vs 77.14% (p=0.012). Pneumonia was the most common 98(80.33%) and had a significant effect on disease severity (p=0.002). Complications from the types of ABI 8(6.56%), ARDS 7(5.74%), sepsis 5(4.1%), DIC 4 (3.28%) and otitis 2(1.64%) were reported only in the group with severe influenza. Acute meningoencephalitis was registered among 5(4.1%), gastroenterocolitis among 3(2.46%), and hepatic damage among 14(11.47%) of patients.

CONCLUSION

Pneumonia as the most common complication among patients with seasonal influenza significantly impacts the clinical course and outcome of the illness.

Future Biomarkers for Infection and Inflammation in Febrile Children

Febrile patients, suffering from an infection, inflammatory disease or autoimmunity may present with similar or overlapping clinical symptoms, which makes early diagnosis difficult. Therefore, biomarkers are needed to help physicians form a correct diagnosis and initiate the right treatment to improve patient outcomes following first presentation or admittance to hospital. Here, we review the landscape of novel biomarkers and approaches of biomarker discovery. We first discuss the use of current plasma parameters and whole blood biomarkers, including results obtained by RNA profiling and mass spectrometry, to discriminate between bacterial and viral infections. Next we expand upon the use of biomarkers to distinguish between infectious and non-infectious disease. Finally, we discuss the strengths as well as the potential pitfalls of current developments. We conclude that the use of combination tests, using either protein markers or transcriptomic analysis, have advanced considerably and should be further explored to improve current diagnostics regarding febrile infections and inflammation. If proven effective when combined, these biomarker signatures will greatly accelerate early and tailored treatment decisions.

Preventing the Risk of Hospitalization for Respiratory Complications of Influenza among the Elderly: Is There a Better Influenza Vaccination Strategy? A Retrospective Population Study

Influenza and its complications are an important public health concern, and vaccination remains the most effective prevention measure. However, the efficacy of vaccination depends on several variables, including the type of strategy adopted. The goal of this study was to assess the impact of different influenza vaccination strategies in preventing hospitalizations for influenza and its related respiratory complications. A retrospective cohort study was conducted on data routinely collected by the health services for six consecutive influenza seasons, considering the population aged 65 years or more at the time of their vaccination and living in northeastern Italy. Our analysis concerns 987,266 individuals vaccinated against influenza during the study period. The sample was a mean 78.0 ± 7.7 years old, and 5681 individuals (0.58%) were hospitalized for potentially influenza-related reasons. The hospitalization rate tended to increase over the years, not-significantly peaking in the 2016-2017 flu season (0.8%). Our main findings revealed that hospitalizations related to seasonal respiratory diseases were reduced as the use of the enhanced vaccine increased (R2 = 0.5234; p < 0.001). Multivariate analysis confirmed the significantly greater protective role of the enhanced vaccine over the conventional vaccination strategy, with adjusted Odds Ratio (adj OR) = 0.62 (95% CI: 0.59-0.66). A prior flu vaccination also had a protective role (adj OR: 0.752 (95% CI: 0.70-0.81)). Age, male sex, and H3N2 mismatch were directly associated with a higher risk of hospitalization for pneumonia. In the second part of our analysis, comparing MF59-adjuvanted trivalent inactivated vaccine (MF59-TIV) with conventional vaccines, we considered 479,397 individuals, of which 3176 (0.66%) were admitted to a hospital. The results show that using the former vaccine reduced the risk of hospitalization by 33% (adj OR: 0.67 (95% CI: 0.59-0.75)). This study contributes to the body of evidence of a greater efficacy of enhanced vaccines, and MF59-adjuvanted TIV in particular, over conventional vaccination strategies in the elderly.

The immune response to influenza in older humans: beyond immune senescence

Despite widespread influenza vaccination programs, influenza remains a major cause of morbidity and mortality in older adults. Age-related changes in multiple aspects of the adaptive immune response to influenza have been well-documented including a decline in antibody responses to influenza vaccination and changes in the cell-mediated response associated with immune senescence. This review will focus on T cell responses to influenza and influenza vaccination in older adults, and how increasing frailty or coexistence of multiple (≥2) chronic conditions contributes to the loss of vaccine effectiveness for the prevention of hospitalization. Further, dysregulation of the production of pro- and anti-inflammatory mediators contributes to a decline in the generation of an effective CD8 T cell response needed to clear influenza virus from the lungs. Current influenza vaccines provide only a weak stimulus to this arm of the adaptive immune response and rely on re-stimulation of CD8 T cell memory related to prior exposure to influenza virus. Efforts to improve vaccine effectiveness in older adults will be fruitless until CD8 responses take center stage.

Use of antiviral drugs for seasonal influenza: Foundation document for practitioners-Update 2019

This document updates the previous AMMI Canada Foundation Guidance (2013) on the use of antiviral therapy for influenza.

The use of maoto (Ma-Huang-Tang), a traditional Japanese Kampo medicine, to alleviate flu symptoms: a systematic review and meta-analysis

BACKGROUND

Influenza is a common viral infection worldwide. Maoto (ma-huang-tang) was developed in ancient China and is used to alleviate flu symptoms. Currently, no meta-analyses have evaluated the efficacy and safety of maoto for alleviating flu symptoms.

METHODS

In the present study, we searched MEDLINE/PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, a Japanese database (Ichushi), two Chinese databases (China National Knowledge Infrastructure and VIP), and two Korean databases (Korean Medical database and Korean Association of Medical Journal Editors) for studies published in or before October 2017. Clinical studies that compared maoto plus neuraminidase inhibitors (NAIs) vs. NAIs alone, or maoto alone vs. NAIs alone, were included in the present analysis. The primary outcome measure (efficacy) was the length of time from the start of medication to resolution of influenza symptoms (fever, headache, malaise, myalgia, and chills) and virus isolation. The secondary outcome measures (safety) were as follows: (1) side effects and adverse reactions, such as nausea, abnormal behaviour, or discontinuation of symptomatic treatment; (2) morbidity (complications caused by influenza infection) or mortality; and (3) hospitalisation for any reason.

RESULTS

Twelve relevant studies were identified, including two randomised controlled trials (RCTs, N = 60) and ten non-randomised studies (NRSs, N = 1110). We found that maoto plus NAIs was superior to NAIs alone in terms of the duration of fever in one RCT (P < 0.05, median difference = - 6 h) and four NRSs (P = 0.003, weighted mean difference = - 5.34 h). The duration of symptoms or virus isolation did not differ between maoto and NAIs. No severe side effects or adverse reactions were reported related to maoto or NAIs.

CONCLUSIONS

Although we could not reach a definitive conclusion because of the small sample sizes and high risk of bias in the analysed studies, maoto may lower the duration of fever when it is used alone or in combination with NAIs and may be a well-tolerated treatment. More RCTs are needed to determine the efficacy and safety of maoto.

Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenzaa

These clinical practice guidelines are an update of the guidelines published by the Infectious Diseases Society of America (IDSA) in 2009, prior to the 2009 H1N1 influenza pandemic. This document addresses new information regarding diagnostic testing, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal influenza. It is intended for use by primary care clinicians, obstetricians, emergency medicine providers, hospitalists, laboratorians, and infectious disease specialists, as well as other clinicians managing patients with suspected or laboratory-confirmed influenza. The guidelines consider the care of children and adults, including special populations such as pregnant and postpartum women and immunocompromised patients.

Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenzaa

These clinical practice guidelines are an update of the guidelines published by the Infectious Diseases Society of America (IDSA) in 2009, prior to the 2009 H1N1 influenza pandemic. This document addresses new information regarding diagnostic testing, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal influenza. It is intended for use by primary care clinicians, obstetricians, emergency medicine providers, hospitalists, laboratorians, and infectious disease specialists, as well as other clinicians managing patients with suspected or laboratory-confirmed influenza. The guidelines consider the care of children and adults, including special populations such as pregnant and postpartum women and immunocompromised patients.

Mortality, morbidity, and hospitalisations due to influenza lower respiratory tract infections, 2017: an analysis for the Global Burden of Disease Study 2017

BACKGROUND

Although the burden of influenza is often discussed in the context of historical pandemics and the threat of future pandemics, every year a substantial burden of lower respiratory tract infections (LRTIs) and other respiratory conditions (like chronic obstructive pulmonary disease) are attributable to seasonal influenza. The Global Burden of Disease Study (GBD) 2017 is a systematic scientific effort to quantify the health loss associated with a comprehensive set of diseases and disabilities. In this Article, we focus on LRTIs that can be attributed to influenza.

METHODS

We modelled the LRTI incidence, hospitalisations, and mortality attributable to influenza for every country and selected subnational locations by age and year from 1990 to 2017 as part of GBD 2017. We used a counterfactual approach that first estimated the LRTI incidence, hospitalisations, and mortality and then attributed a fraction of those outcomes to influenza.

FINDINGS

Influenza LRTI was responsible for an estimated 145 000 (95% uncertainty interval [UI] 99 000-200 000) deaths among all ages in 2017. The influenza LRTI mortality rate was highest among adults older than 70 years (16·4 deaths per 100 000 [95% UI 11·6-21·9]), and the highest rate among all ages was in eastern Europe (5·2 per 100 000 population [95% UI 3·5-7·2]). We estimated that influenza LRTIs accounted for 9 459 000 (95% UI 3 709 000-22 935 000) hospitalisations due to LRTIs and 81 536 000 hospital days (24 330 000-259 851 000). We estimated that 11·5% (95% UI 10·0-12·9) of LRTI episodes were attributable to influenza, corresponding to 54 481 000 (38 465 000-73 864 000) episodes and 8 172 000 severe episodes (5 000 000-13 296 000).

INTERPRETATION

This comprehensive assessment of the burden of influenza LRTIs shows the substantial annual effect of influenza on global health. Although preparedness planning will be important for potential pandemics, health loss due to seasonal influenza LRTIs should not be overlooked, and vaccine use should be considered. Efforts to improve influenza prevention measures are needed.

FUNDING

Bill & Melinda Gates Foundation.

Perceptions of Seasonal Influenza and Pneumococcal Vaccines Among Older Chinese Adults

BACKGROUND AND OBJECTIVES

Seasonal influenza can lead to pneumonia. In Hong Kong, deaths from pneumonia increased steadily from 2001 to 2015, and pneumonia was the second most common cause of death between 2012 and 2015. The seasonal influenza vaccine and pneumococcal vaccine have been clinically proven as effective measures against these two diseases among older adults, who are at particularly high risk. Despite the availability of vaccine subsidies, however, more than 60% of older adults in Hong Kong remain unvaccinated against pneumococcal diseases and seasonal influenza. The objective of this study was to investigate the perceptions and barriers associated with the seasonal influenza and pneumococcal vaccinations among older adults in Hong Kong.

RESEARCH DESIGN AND METHODS

A qualitative approach of individual semistructured interviews was adopted; 40 adults aged 65 years and older were interviewed between September and November 2016.

RESULTS

The intersecting influences of belief of vaccines as harmful, low perceived risk of contracting the diseases, negative rumors about the vaccines, lack of promotion by health care providers, the perceived risk posed by the vaccinating locations, and the preference of using traditional Chinese medicine were discovered to prevent the participants from receiving the two vaccinations.

DISCUSSION AND IMPLICATIONS

Perceptions and cultural factors should be considered in future vaccination promotion among older adults. This study found that, in particular, the participants' cultural associations and stereotypes of hospitals and clinics and health care providers' lack of perceived need to vaccinate older adults contributed to low vaccine acceptance among the participants.

[Influenza and secondary bacterial infections: threats and treatments]

Influenza virus infection ("flu") constitutes an important public health issue and is associated with a significant socio-economic burden. The discovery of new antivirals and a better understanding of antiviral immunity might offer new options for preventing or controlling flu infections. A better understanding of the underlying pathomechanism might also prompt the discovery of key molecules whose activity could be modulated in a clinical setting. Lastly, the development of new immunomodulators and immunostimulants might compensate for impaired host defense mechanisms and improve resistance to secondary bacterial infections, since the latter significantly worsen the clinical status of influenza-infected patients.

The Influence of Influenza and Pneumococcal Vaccines on Community-Acquired Pneumonia (CAP) Outcomes Among Elderly Patients

Elderly are at high risk for hospitalization for community-acquired pneumonia (CAP), especially due to Streptococcus pneumoniae, and seasonal influenza viruses. Data suggest PPV23's influence on various CAP-related outcomes among the elderly may depend upon how many years have elapsed since they received this vaccine. PPV23's protection against invasive pneumococcal disease and CAP hospitalizations are often limited to moderately ill elderly, who are less than 75 years old, or female. PCV13 demonstrates broad protection against a variety of CAPs, but ultimately, its influence on their outcomes among the elderly may be limited by herd immunity from PCV7 use. Influenza vaccine's indirect protective effect against all-cause and non-invasive pneumococcal CAP in the elderly is difficult to ascertain. The use of both PPV23 and influenza vaccine shortens length of stay in hospitalized elderly with CAP, but whether that benefit would be realized in the presence of herd immunity is unknown.