Burden of seasonal influenza in children with neurodevelopmental conditions

Trends in Outpatient Influenza Antiviral Use Among Children and Adolescents in the United States

BACKGROUND

Influenza antivirals improve outcomes in children with duration of symptoms <2 days and those at high risk for influenza complications. Real-world prescribing of influenza antivirals in the pediatric population is unknown.

METHODS

We performed a cross-sectional study of outpatient and emergency department prescription claims in individuals <18 years of age included in the IBM Marketscan Commercial Claims and Encounters Database between July 1, 2010 and June 30, 2019. Influenza antiviral use was defined as any dispensing of oseltamivir, baloxavir, or zanamivir. The primary outcome was the rate of antiviral dispensing per 1000 enrolled children. Secondary outcomes included antiviral dispensing per 1000 influenza diagnoses and inflation-adjusted costs of antiviral agents. Outcomes were calculated and stratified by age, acute versus prophylactic treatment, influenza season, and geographic region.

RESULTS

The analysis included 1 416 764 unique antiviral dispensings between 2010 and 2019. Oseltamivir was the most frequently prescribed antiviral (99.8%). Dispensing rates ranged from 4.4 to 48.6 per 1000 enrolled children. Treatment rates were highest among older children (12-17 years of age), during the 2017 to 2018 influenza season, and in the East South Central region. Guideline-concordant antiviral use among young children (<2 years of age) at a high risk of influenza complications was low (<40%). The inflation-adjusted cost for prescriptions was $208 458 979, and the median cost ranged from $111 to $151.

CONCLUSIONS

There is wide variability and underuse associated with influenza antiviral use in children. These findings reveal opportunities for improvement in the prevention and treatment of influenza in children.

Primary oxidative phosphorylation defects lead to perturbations in the human B cell repertoire

Introduction

The majority of studies on oxidative phosphorylation in immune cells have been performed in mouse models, necessitating human translation. To understand the impact of oxidative phosphorylation (OXPHOS) deficiency on human immunity, we studied children with primary mitochondrial disease (MtD).

Methods

scRNAseq analysis of peripheral blood mononuclear cells was performed on matched children with MtD (N = 4) and controls (N = 4). To define B cell function we performed phage display immunoprecipitation sequencing on a cohort of children with MtD (N = 19) and controls (N = 16).

Results

Via scRNAseq, we found marked reductions in select populations involved in the humoral immune response, especially antigen presenting cells, B cell and plasma populations, with sparing of T cell populations. MTRNR2L8, a marker of bioenergetic stress, was significantly elevated in populations that were most depleted. mir4485, a miRNA contained in the intron of MTRNR2L8, was co-expressed. Knockdown studies of mir4485 demonstrated its role in promoting survival by modulating apoptosis. To determine the functional consequences of our findings on humoral immunity, we studied the antiviral antibody repertoire in children with MtD and controls using phage display and immunoprecipitation sequencing. Despite similar viral exposomes, MtD displayed antiviral antibodies with less robust fold changes and limited polyclonality.

Discussion

Overall, we show that children with MtD display perturbations in the B cell repertoire which may impact humoral immunity and the ability to clear viral infections.

Epitope-level profiling in children with mitochondrial disease reveals limitations in the antibacterial antibody repertoire

INTRODUCTION

Immunometabolic studies in mice have suggested the importance of oxidative phosphorylation (OXPHOS) in humoral immunity. However, there are important distinctions between murine and human immunity. Furthermore, translational studies on the role of OXPHOS in humoral immunity are nearly absent from the biomedical literature. Children with primary OXPHOS deficiency (i.e., mitochondrial disease, MtD), are an important patient population for demonstrating the functional effects of this bioenergetic defect on humoral immunity.

METHODS

To define whether OXPHOS deficiency extended to human B cells, we performed extracellular flux analysis on lymphoblastoid B cell lines from children with MtD and controls (N = 4/group). To expand the immune phenotype of B cell OXPHOS deficiency, we conducted a cross-sectional multiplex serology study of the antibacterial antibody repertoire in children with MtD (N = 16) and controls (N = 16) using phage display and immunoprecipitation sequencing (PhIPseq). The PhIPseq library contained >3000 peptides (i.e., epitopes) covering >40 genera and > 150 species of bacteria that infect humans.

RESULTS

B cell lymphoblastoid cell lines from children with MtD displayed depressed baseline oxygen consumption, ATP production and reserve capacity, indicating that OXPHOS deficiency extended to these key cells in humoral immunity. Characterization of the bacterial exposome revealed comparable bacterial species between the two groups, mostly Streptococcus and Staphylococcus. The most common species of bacteria was S. pneumoniae. By interrogating the antibacterial antibody repertoire, we found that children with MtD had less robust antibody fold changes to common epitopes. Furthermore, we also found that children with MtD failed to show a direct relationship between the number of bacterial epitopes recognized and age, unlike controls. OXPHOS deficiency extends to B cells in children with MtD, leading to limitations in the antibacterial antibody repertoire. Furthermore, the timing of bacterial exposures was asynchronous, suggesting different periods of increased exposure or susceptibility.

CONCLUSIONS

Overall, the antibacterial humoral response is distinctive in children with MtD, suggesting an important role for OXPHOS in B cell function.

Guideline-Concordant Antiviral Treatment in Children at High Risk for Influenza Complications

BACKGROUND

National guidelines recommend antiviral treatment for children with influenza at high risk for complications regardless of symptom duration. Little is known about concordance of clinical practice with this recommendation.

METHODS

We performed a cross-sectional study of outpatient children (aged 1-18 years) at high risk for complications who were diagnosed with influenza during the 2016-2019 influenza seasons. High-risk status was determined using an existing definition that includes age, comorbidities, and residence in a long-term care facility. The primary outcome was influenza antiviral dispensing within 2 days of influenza diagnosis. We determined patient- and provider-level factors associated with guideline-concordant treatment using multivariable logistic regression.

RESULTS

Of the 274 213 children with influenza at high risk for influenza complications, 159 350 (58.1%) received antiviral treatment. Antiviral treatment was associated with the presence of asthma (aOR, 1.13; 95% confidence interval [CI], 1.11-1.16), immunosuppression (aOR, 1.10; 95% CI, 1.05-1.16), complex chronic conditions (aOR, 1.04; 95% CI, 1.01-1.07), and index encounter in the urgent care setting (aOR, 1.3; 95% CI, 1.26-1.34). Factors associated with decreased odds of antiviral treatment include age 2-5 years compared with 6-17 years (aOR, 0.95; 95% CI, .93-.97), residing in a chronic care facility (aOR, .61; 95% CI, .46-.81), and index encounter in an emergency department (aOR, 0.66; 95% CI, .63-.71).

CONCLUSIONS

Among children with influenza at high risk for complications, 42% did not receive guideline-concordant antiviral treatment. Further study is needed to elucidate barriers to appropriate use of antivirals in this vulnerable population.

Multidrug-resistant organisms in paediatric palliative care patients - Prevalence, risk factors and the impact of a liberal hygiene concept

AIM

Multidrug-resistant organisms (MDRO) deserve special attention in health-care facilities for children with life-limiting conditions because these children have an increased risk for colonisation. To avoid nosocomial transmissions to other inpatients, single-room isolation is usually recommended. In the context of paediatric palliative care (PPC), such isolation counters the aim of participation in social activities for the patients. This study aimed to determine the prevalence of MDRO, the predictive value of risk factors and the incidence of nosocomial infections and nosocomial colonisations on a PPC inpatient unit applying a special hygiene concept that enables participation in social activities through risk-adaption and barrier nursing.

METHODS

Two-year surveillance with MDRO screening of all intakes (N = 386) of a PPC unit on the day of admission and discharge. To determine the predictive value of pre-defined risk factors, logistic regression analyses were calculated. Receiver operating characteristic analyses were performed to determine the predictive power of the number of risk factors on the presence of MDRO.

RESULTS

The rate of MDRO colonisation at admission was 12.7%; previous positive MDRO screening was the only significant individual risk factor. Over the 2-year period, no MDRO-related nosocomial infections occurred; nosocomial colonisation incidence density was 0.6.

CONCLUSION

Results demonstrate that patients with at least one risk factor have to be cared for by barrier nursing until MDRO screening results are negative. Following these guidelines prevents nosocomial MDRO transmission.

Characteristics of children admitted to hospital with acute SARS-CoV-2 infection in Canada in 2020

Background:

Risk factors for severe outcomes of SARS-CoV-2 infection are not well established in children. We sought to describe pediatric hospital admissions associated with SARS-CoV-2 infection in Canada and identify risk factors for more severe disease.

Methods:

We conducted a national prospective study using the infrastructure of the Canadian Paediatric Surveillance Program (CPSP). Cases involving children who were admitted to hospital with microbiologically confirmed SARS-CoV-2 infection were reported from Apr. 8 to Dec. 31 2020, through weekly online questionnaires distributed to the CPSP network of more than 2800 pediatricians. We categorized hospital admissions as related to COVID-19, incidental, or for social or infection control reasons and determined risk factors for disease severity in hospital.

Results:

Among 264 hospital admissions involving children with SARS-CoV-2 infection during the 9-month study period, 150 (56.8%) admissions were related to COVID-19 and 100 (37.9%) were incidental infections (admissions for other reasons and found to be positive for SARS-CoV-2 on screening). Infants (37.3%) and adolescents (29.6%) represented most cases. Among hospital admissions related to COVID-19, 52 (34.7%) had critical disease, 42 (28.0%) of whom required any form of respiratory or hemodynamic support, and 59 (39.3%) had at least 1 underlying comorbidity. Children with obesity, chronic neurologic conditions or chronic lung disease other than asthma were more likely to have severe or critical COVID-19.

Interpretation:

Among children who were admitted to hospital with SARS-CoV-2 infection in Canada during the early COVID-19 pandemic period, incidental SARS-CoV-2 infection was common. In children admitted with acute COVID-19, obesity and neurologic and respiratory comorbidities were associated with more severe disease.

Vaccine coverage among children with epilepsy in two Canadian provinces: A Canadian immunization research network study

OBJECTIVES

Children with epilepsy are at increased risk of complications from vaccine-preventable infections, yet information on vaccine coverage in these children is scarce. We aimed to compare vaccine coverage among children with epilepsy to children without epilepsy.

STUDY DESIGN

We conducted a retrospective cohort study including all 2005-2013 births in Manitoba and Ontario, Canada, creating two cohorts: 2-year-olds and 7-year-olds (followed to age 2 and 7 years). We split each cohort into epilepsy and non-epilepsy subcohorts. We assessed vaccination coverage based on provincial schedules and determined timeliness of MMR (measles, mumps, rubella) dose 1 (recommended at 12 months) and DTaP (diphtheria, tetanus, pertussis) dose 4 (recommended at 18 months). We used logistic regression to calculate adjusted odds ratios (aORs) of the association between epilepsy and vaccination, combining both provincial estimates using random effects meta-analysis.

RESULTS

We included 16,558 2-year-olds (Manitoba, 653; Ontario, 15,905) and 13,004 7-year-olds (Manitoba, 483; Ontario, 12,521) with epilepsy. At age 2 years, the aOR for up-to-date vaccination among children with versus without epilepsy was 0.9 (95% confidence interval 0.8-1.1); at age 7 years it was 1.0 (0.9-1.1). Infants diagnosed with epilepsy before age 6 months were less likely to be up-to-date at age 2 years (0.9; 0.8-0.9), although this difference disappeared by age 7 years. Vaccine timeliness was similar between children with and without epilepsy for MMR dose 1 and DTaP dose 4.

CONCLUSIONS

Overall, this study suggests that children with epilepsy are not significantly under-vaccinated compared to their peers without epilepsy. As children with epilepsy are at a higher risk of complications from vaccine-preventable diseases, vaccination in children with epilepsy should be optimized, especially early in life, as these children may not be able to rely on herd protection.

The effect of multidrug-resistant organisms on social participation and quality of life in children with life-limiting conditions

BACKGROUND

Children with life-limiting conditions have a high risk of colonisation with a multidrug-resistant organism (MDRO). To avoid the spread of hospital-aquired infections to other patients, children with a MDRO are moved to an isolated room or ward. However, such isolation prevents social participation, which may reduce the child's quality of life (QoL). To overcome this challenge of conflicting interests on a paediatric palliative care inpatient unit, a hygiene concept for patients colonised with MDRO, called PALLINI, was implemented. PALLINI advises that, instead of isolating the affected children, strict barrier nursing should be used.

AIM

To identify the impact of a complex hygiene concept on children's and parents' QoL and social participation.

METHODS

Cross-sectional mixed-methods research approach, comprising semi-structured interviews with parents and staff members, and a QoL-questionnaire focusing on the child which was completed by parents.

FINDINGS

In paediatric patients with life-limiting conditions who have MDRO colonisation, using a complex hygiene protocol resulted in both benefits and barriers to social participation. However, the child's QoL did not appear to be affected.

CONCLUSION

All staff members and families have to be familiar with the hygiene concept and the concept has to be self-explanatory and easy to apply.

Influenza in High-Risk Hosts-Lessons Learned from Animal Models

Factoring significantly into the global burden of influenza disease are high-risk populations that suffer the bulk of infections. Classically, the very young, very old, and pregnant women have been identified as high-risk populations; however, recent research has uncovered several other conditions that contribute to severe infection. By using varied animal models, researchers have identified molecular mechanisms underpinning the increased likelihood for infection due to obesity and malnourishment, as well as insight into the role sex hormones play in antiviral immunity in males, in females, and across the life span. Additionally, novel comorbidity models have helped elucidate the role of chronic infectious and genetic diseases in influenza virus pathogenesis. Animal models play a vital role in understanding the contribution of host factors to influenza severity and immunity. An in-depth understanding of these host factors represents an important step in reducing the burden of influenza among the growing number of people living with one or more chronic medical conditions.

Active surveillance of acute paediatric hospitalisations demonstrates the impact of vaccination programmes and informs vaccine policy in Canada and Australia

Sentinel surveillance of acute hospitalisations in response to infectious disease emergencies such as the 2009 influenza A(H1N1)pdm09 pandemic is well described, but recognition of its potential to supplement routine public health surveillance and provide scalability for emergency responses has been limited. We summarise the achievements of two national paediatric hospital surveillance networks relevant to vaccine programmes and emerging infectious diseases in Canada (Canadian Immunization Monitoring Program Active; IMPACT from 1991) and Australia (Paediatric Active Enhanced Disease Surveillance; PAEDS from 2007) and discuss opportunities and challenges in applying their model to other contexts. Both networks were established to enhance capacity to measure vaccine preventable disease burden, vaccine programme impact, and safety, with their scope occasionally being increased with emerging infectious diseases’ surveillance. Their active surveillance has increased data accuracy and utility for syndromic conditions (e.g. encephalitis), pathogen-specific diseases (e.g. pertussis, rotavirus, influenza), and adverse events following immunisation (e.g. febrile seizure), enabled correlation of biological specimens with clinical context and supported responses to emerging infections (e.g. pandemic influenza, parechovirus, COVID-19). The demonstrated long-term value of continuous, rather than incident-related, operation of these networks in strengthening routine surveillance, bridging research gaps, and providing scalable public health response, supports their applicability to other countries.

Adverse Events Following Immunization Among Children With Epilepsy: A Self-Controlled Case Series

BACKGROUND

In children with epilepsy, fever and illness are known triggers for seizure; therefore, clinicians and parents could be concerned that immunization-induced inflammation and fever could also trigger seizures. We sought to estimate the risk of emergency department (ED) visit or hospitalization for epilepsy/seizure and all causes after immunization in children younger than 7 years of age with epilepsy.

METHODS

We conducted a self-controlled case series of children diagnosed with epilepsy before their 7th birthday and immunized from 2005 to 2015 in Ontario (population 14.2 million) and Manitoba (population 1.3 million), Canada, using administrative healthcare data. We estimated the age- and season-adjusted relative incidence (aRI) of epilepsy/seizure-related and all-cause ED visits/hospitalizations during various risk periods 0-28 days after inactivated and live immunizations versus a control period 35-83 days postimmunization. Estimates from each province were analyzed separately and then combined in a random-effects meta-analysis.

RESULTS

The combined risk of epilepsy/seizure-related hospitalization/ED visit was increased 0-2 days after inactivated vaccines (aRI = 1.5, 95% confidence interval: 1.1-1.9) and 7-10 days after live vaccines (aRI = 1.9, 1.4-2.7). For all-cause ED visit/hospitalization, the combined aRI estimate was 0.9 (0.8-1.2) 0-2 days after inactivated vaccines and 1.3 (1.1-1.5) 7-10 days after live vaccines.

CONCLUSIONS

The risk of epilepsy/seizure-related ED visit/hospitalization was modestly increased among children with epilepsy during peak periods of fever and inflammation following inactivated and live vaccines. These risks must be balanced against the risk of complications from vaccine-preventable diseases.

Addressing multidrug resistant pathogens in pediatric palliative care patients-the nurses point of view: A qualitative study

BACKGROUND

Multidrug resistant pathogens are a large-scale healthcare issue. In particular, children with life-limiting conditions have a significantly increased risk of multidrug resistant pathogen colonization. Official hygiene requirements recommend children, who are colonized with multidrug resistant pathogens, to be isolated. In the context of pediatric palliative care, such isolation adversely affects the aim of social participation. To overcome this challenge of conflicting interests on a pediatric palliative care inpatient unit, a hygiene concept for patients colonized with multidrug resistant pathogens, called PALLINI, was implemented.

AIM

The aim of this study was to identify the nurses' attitudes and opinions toward PALLINI.

METHODS

Nurses (N = 14) from the pediatric palliative care unit were queried in guideline-oriented interviews. Interviews were analyzed qualitatively by means of content analysis.

RESULTS

The following four categories were identified: (1) safety, (2) effort, (3) quality of care, and (4) participation. All categories demonstrated ambivalence by nursing staff regarding PALLINI. Ambivalence arose from guaranteeing infection control versus noncompliance by the families, additional workload for patients with multidrug resistant pathogens versus lack of resources, impaired relationship with the parents versus enabling better care for the child, as well as enabling some limited contact versus the larger goal of genuine social participation. Despite this, nurses reported the importance of arranging everyday-life for the patients so that they experience as much social participation as possible.

CONCLUSION

The implementation of a new hygiene concept is challenging. Despite positive reception of PALLINI from the nurses, ambivalence remained. Addressing these ambivalences may be critical to best implement the new hygiene concept.

Multidrug-resistant bacteria in a paediatric palliative care inpatient unit: results of a one year surveillance

Aim: Nosocomial infections (NIs) and multidrug resistant (MDR) pathogens are an important paediatric healthcare issue. In vulnerable patients such as children with life-limiting conditions, MDR infections can be life-threatening. Additionally, these children have a significantly increased risk for colonisation with MDR pathogens. Therefore, it is vital to prevent new colonisations with MDR pathogens in this vulnerable patient group. However, little is known about colonisation with MDR pathogens and NIs in inpatient units for paediatric palliative care (PPC). The aim of this study was to investigate the prevalence of colonisation with MDR pathogens and the incidence of NIs in a PPC unit. Methods: Evaluation of surveillance data of a PPC unit. All patients admitted to a PPC unit from 1^st April 2012 to 31^st March 2013 were screened for MDR pathogens upon admission. Patients who exhibited clinical signs of an infection during their inpatient stay were screened again. Results: During the study period, 198 cases were admitted to the unit. Those cases represent 118 patients. 18% of the patients were colonised with MDR pathogens. The most common MDR pathogens were E. coli (8.1%) and Pseudomonas ssp. (8.1%). In addition, 58% of patients with tracheostomy had MDR pathogens in their tracheal secretions. The incidence density of NIs was 0.99 per 1000 inpatient treatment days with no NI caused by MDR pathogens. Conclusion: Due to a high prevalence, it is reasonable to screen PPC patients for MDR pathogen colonisation before or during admission. Special attention must be given to patients with tracheostomy. Our results provide preliminary evidence that participation in social activities in a PPC unit for patients colonised with MDR pathogens is safe if hygiene concepts are applied.

Evaluation of the field-protective effectiveness of seasonal influenza vaccine among Korean children aged < 5 years during the 2014-2015 and 2015-2016 influenza seasons: a cohort study

BACKGROUND

A field effectiveness evaluation of the influenza vaccine among children younger than five years is important due to the high burden of influenza in this age group. The epidemiology of influenza virus changes rapidly each year. Moreover, the development of a new type of influenza vaccine is accelerating, necessitating a new field effectiveness evaluation.

METHODS

This multi-center, open-label cohort study was conducted in the northern part of Seoul from December 2014 to May 2015 and in Gyeong-gi Province from December 2015 to May 2016. The cohort comprised an influenza vaccinated group and non-vaccinated group. During the influenza seasons, we conducted influenza rapid tests and polymerase chain reaction assays for individuals with suspected influenza and checked for the presence of influenza virus. We calculated the influenza vaccine effectiveness by comparing the incidence rates of influenza between the vaccinated and non-vaccinated groups.

RESULTS

During the 2014-2015 season, the field effectiveness of the influenza vaccine was 38.4%. In particular, the vaccine effectiveness against type A influenza virus was 50.7%. During the 2015-2016 season, the vaccine effectiveness reached 23.8% and the vaccine effectiveness against type A influenza virus was 48.5%. The vaccine effectiveness against influenza B virus was markedly reduced in both seasons.

CONCLUSION

The influenza vaccine was supposed to be effective against influenza A, but may have a limited effectiveness against influenza B among Korean children aged < 5 years.

Influenza and other respiratory viruses: standardizing disease severity in surveillance and clinical trials

INTRODUCTION

Influenza-Like Illness is a leading cause of hospitalization in children. Disease burden due to influenza and other respiratory viral infections is reported on a population level, but clinical scores measuring individual changes in disease severity are urgently needed. Areas covered: We present a composite clinical score allowing individual patient data analyses of disease severity based on systematic literature review and WHO-criteria for uncomplicated and complicated disease. The 22-item ViVI Disease Severity Score showed a normal distribution in a pediatric cohort of 6073 children aged 0-18 years (mean age 3.13; S.D. 3.89; range: 0 to 18.79). Expert commentary: The ViVI Score was correlated with risk of antibiotic use as well as need for hospitalization and intensive care. The ViVI Score was used to track children with influenza, respiratory syncytial virus, human metapneumovirus, human rhinovirus, and adenovirus infections and is fully compliant with regulatory data standards. The ViVI Disease Severity Score mobile application allows physicians to measure disease severity at the point-of care thereby taking clinical trials to the next level.

Severe influenza in children: incidence and risk factors

INTRODUCTION

The identification of factors that can predispose to the development of severe influenza is essential to enable the implementation of optimal prevention and control measures for vulnerable populations.

AREAS COVERED

Unfortunately, data in the pediatric age group remain difficult to interpret. However, epidemiological data seem to suggest that the most severe influenza cases, those who are hospitalized, those who are admitted to the intensive care unit, and those who died, occur in children in the first 2 years of life and in school age patients. Expert commentary: Immaturity of the immune system, and in particular of the mechanisms that usually recognize influenza viruses and activate cytokine and chemokine responses to reduce viral replication, might explain the high hospitalization rate observed in the youngest patients. Some underlying chronic conditions favour the development of the severe cases, sometime leading to death, although both admission to the intensive care unit and death can occur in otherwise healthy subjects.

Improving Accuracy of Influenza-Associated Hospitalization Rate Estimates

Adjusting for diagnostic test sensitivity enables more accurate and timely comparisons over time.

Diagnostic test sensitivity affects rate estimates for laboratory-confirmed influenza–associated hospitalizations. We used data from FluSurv-NET, a national population-based surveillance system for laboratory-confirmed influenza hospitalizations, to capture diagnostic test type by patient age and influenza season. We calculated observed rates by age group and adjusted rates by test sensitivity. Test sensitivity was lowest in adults >65 years of age. For all ages, reverse transcription PCR was the most sensitive test, and use increased from <10% during 2003–2008 to ≈70% during 2009–2013. Observed hospitalization rates per 100,000 persons varied by season: 7.3–50.5 for children <18 years of age, 3.0–30.3 for adults 18–64 years, and 13.6–181.8 for adults >65 years. After 2009, hospitalization rates adjusted by test sensitivity were ≈15% higher for children <18 years, ≈20% higher for adults 18–64 years, and ≈55% for adults >65 years of age. Test sensitivity adjustments improve the accuracy of hospitalization rate estimates.

Impact of Influenza on Outpatient Visits, Hospitalizations, and Deaths by Using a Time Series Poisson Generalized Additive Model

BACKGROUND

The disease burden associated with influenza in developing tropical and subtropical countries is poorly understood owing to the lack of a comprehensive disease surveillance system and information-exchange mechanisms. The impact of influenza on outpatient visits, hospital admissions, and deaths has not been fully demonstrated to date in south China.

METHODS

A time series Poisson generalized additive model was used to quantitatively assess influenza-like illness (ILI) and influenza disease burden by using influenza surveillance data in Zhuhai City from 2007 to 2009, combined with the outpatient, inpatient, and respiratory disease mortality data of the same period.

RESULTS

The influenza activity in Zhuhai City demonstrated a typical subtropical seasonal pattern; however, each influenza virus subtype showed a specific transmission variation. The weekly ILI case number and virus isolation rate had a very close positive correlation (r = 0.774, P < 0.0001). The impact of ILI and influenza on weekly outpatient visits was statistically significant (P < 0.05). We determined that 10.7% of outpatient visits were associated with ILI and 1.88% were associated with influenza. ILI also had a significant influence on the hospitalization rates (P < 0.05), but mainly in populations <25 years of age. No statistically significant effect of influenza on hospital admissions was found (P > 0.05). The impact of ILI on chronic obstructive pulmonary disease (COPD) was most significant (P < 0.05), with 33.1% of COPD-related deaths being attributable to ILI. The impact of influenza on the mortality rate requires further evaluation.

CONCLUSIONS

ILI is a feasible indicator of influenza activity. Both ILI and influenza have a large impact on outpatient visits. Although ILI affects the number of hospital admissions and deaths, we found no consistent influence of influenza, which requires further assessment.

Vaccine recommendations for children and youth for the 2015/2016 influenza season

The Canadian Paediatric Society continues to encourage annual influenza vaccination for ALL children and youth ≥6 months of age. Recommendations from the National Advisory Committee on Immunization for the 2015/2016 influenza season include some important changes: Children and adolescents with neurological or neurodevelopmental disorders were added to the list of individuals considered to be at high risk for severe influenza.Quadrivalent influenza vaccines are recommended preferentially over trivalent vaccines for use in children and youth.An adjuvanted trivalent inactivated influenza vaccine is now available for use in children six to 23 months of age.

Summary of the National Advisory Committee on Immunization (NACI) Statement on Seasonal Influenza Vaccine for 2015-2016

Background

The National Advisory Committee on Immunization (NACI) provides the Public Health Agency of Canada with ongoing and timely medical, scientific, and public health advice relating to immunization.

Objective

To summarize the update of the 2015-2016 recommendations by NACI regarding the use of seasonal influenza vaccines.

Methods

Annual influenza vaccine recommendations are developed by the Influenza Working Group for consideration by NACI, based on NACI's evidence-based process for developing recommendations, and includes: a consideration of the burden of influenza illness and the target populations for vaccination; efficacy and effectiveness, immunogenicity, and safety of influenza vaccines; vaccine schedules; and other aspects of influenza immunization.

Results

NACI continues to recommend influenza vaccination for all individuals aged 6 months and older, with particular focus on people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk, and others as indicated. For the 2015-2016 influenza season, the Statement has been updated to identify children and adolescents with neurologic or neurodevelopment conditions as a group at high risk for influenza-related complications or hospitalization. Several changes to product availability in Canada have also been noted. A new adjuvanted, trivalent influenza vaccine (Fluad Pediatric™ [Novartis]) will be available for use in children aged 6 to <24 months. The recommended choice of product for this age group, however, is quadrivalent inactivated influenza vaccine (QIV), because children are more likely to be affected by influenza B, and the QIV provides broader protection against both lineages of influenza B. If QIV is not available, either unadjuvanted or adjuvanted trivalent inactivated influenza vaccine (TIV) should be used. Only the quadrivalent formulation of the live attenuated influenza vaccine (LAIV) (FluMist® Quadrivalent [AstraZeneca]) will be available, and the recommendation for preferential use of LAIV in children 2 to 17 years of age who do not have contraindications to this vaccine remains unchanged following a review of information pertaining to reports of decreased effectiveness of LAIV in the United States during the 2013-2014 season. Finally, the intradermal trivalent influenza vaccine (Intanza® [Sanofi Pasteur]) will no longer be available for use in Canada. Other updates to the Statement include additional information reaffirming the safety of LAIV use in children with cystic fibrosis who are not considered immunosuppressed or receiving immunosuppressive treatment, as well as a revised definition for oculo-respiratory syndrome which, when it occurs, should be reported as an adverse event following immunization (AEFI) to local public health officials.

Conclusion

Vaccination is the safest, longest lasting and most effective way to prevent influenza.