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There is limited information on the volume of antibiotic prescribing that is influenza-associated, resulting from influenza infections and their complications (such as streptococcal pharyngitis). We estimated that for the Kaiser Permanente Northern California population during 2010–2018, 3.4% (2.8%–4%) of all macrolide prescriptions (fills), 2.7% (2.3%–3.2%) of all aminopenicillin prescriptions, 3.1% (2.4%–3.9%) of all 3rd generation cephalosporins prescriptions, 2.2% (1.8%–2.6%) of all protected aminopenicillin prescriptions and 1.3% (1%–1.6%) of all quinolone prescriptions were influenza-associated. The corresponding proportions were higher for select age groups, e.g. 4.3% of macrolide prescribing in ages over 50 years, 5.1% (3.3%–6.8%) of aminopenicillin prescribing in ages 5–17 years and 3.3% (1.9%–4.6%) in ages <5 years was influenza-associated. The relative contribution of influenza to antibiotic prescribing for respiratory diagnoses without a bacterial indication in ages over 5 years was higher than the corresponding relative contribution to prescribing for all diagnoses. Our results suggest a modest benefit of increasing influenza vaccination coverage for reducing prescribing for the five studied antibiotic classes, particularly for macrolides in ages over 50 years and aminopenicillins in ages <18 years, and the potential benefit of other measures to reduce unnecessary antibiotic prescribing for respiratory diagnoses with no bacterial indication, both of which may contribute to the mitigation of antimicrobial resistance.
We recently described a simple model through which we assessed what effect subjecting travellers to a single on-arrival test might have on reducing risk of importing disease cases during simulated outbreaks of coronavirus disease 2019 (COVID-19), influenza, severe acute respiratory syndrome (SARS) and Ebola. We build upon this work to allow for the additional requirement that inbound travellers also undergo a period of self-isolation upon arrival, where upon completion the traveller is again tested for signs of infection prior to admission across the border. Prior results indicated that a single on-arrival test has the potential to detect 9% of travellers infected with COVID-19, compared to 35%, 10% and 3% for travellers infected with influenza, SARS and Ebola, respectively. Our extended model shows that testing administered after a 2-day isolation period could detect up to 41%, 97%, 44% and 15% of COVID-19, influenza, SARS and Ebola infected travellers, respectively. Longer self-isolation periods increase detection rates further, with an 8-day self-isolation period suggesting detection rates of up to 94%, 100%, 98% and 62% for travellers infected with COVID-19, influenza, SARS and Ebola, respectively. These results therefore suggest that testing arrivals after an enforced period of self-isolation may present a reasonable method of protecting against case importation during international outbreaks.
This study aimed to assess the feasibility and acceptability of implementing non-pharmaceutical interventions (NPIs) reserved for influenza pandemics (voluntary home quarantine, use of face masks by ill persons, childcare facility closures, school closures, and social distancing at schools, workplaces, and mass gatherings).
Public health officials in all 50 states (including Washington, DC) and 8 territories, and a random sample of 822 local health departments (LHDs), were surveyed in 2019.
The response rates for the states/ territories and LHDs were 75% (44/ 59) and 25% (206/ 822), respectively. Most of the state/ territorial respondents stated that the feasibility and acceptability of implementing NPIs were high, except for K-12 school closures lasting up to 6 weeks or 6 months. The LHD respondents also indicated that feasibility and acceptability were lowest for prolonged school closures. Compared to LHD respondents in suburban or urban areas, those in rural areas expressed lower feasibility and acceptability. Barriers to implementing NPIs included financial impact, compliance and difficulty in enforcement, perceived level of disease threat, and concerns regarding political implications.
Proactive strategies to systematically address perceived barriers and promote disease prevention ahead of a new pandemic are needed to increase receptivity and consistent adoption of NPIs and other evidence-based countermeasures.
Older adults have an increased risk of complications or death from influenza. Despite the benefits of vaccination for older adults, vaccination coverage among older adults ages 65 years and over is still below Canada’s national target of 80 per cent. As health–care-seeking behaviours are influenced by several factors, including life satisfaction, we investigated the relationship between life satisfaction and influenza vaccination among older adults. A sample (n = 22,424) from the 2015–2016 Canadian Community Health Survey data was analysed using descriptive and multinomial logistic regression analyses. Higher life satisfaction was associated with a more recent influenza vaccination history. Vaccination differed by gender, age, and self-reported health status, as women, much older adults, and those with the poorest health status were more likely to be vaccinated. The study suggests an association between life satisfaction and influenza vaccination. More research into the factors that impact influenza vaccination in older adults is needed to increase vaccination coverage in the older adult population.
As the population in the United States continues to age, familiarity with the clinical presentation, diagnosis, and management of the major serious infections of elderly individuals becomes an increasingly critical component of general medicine and primary care. While modern medicine has significantly reduced early death due to infection, diseases caused by infectious pathogens remain a major cause of illness and death among elderly persons. This chapter reviews the immunology of the elder host and environmental factors that make older adults uniquely vulnerable to infectious diseases. We propose an approach to the elderly patient with suspected infectious disease and highlight the differences in clinical presentation among older and younger patients, as well as addressing diagnosis and management of common and serious infectious diseases of older adults including urinary tract infection, bacterial pneumonia, influenza, herpes zoster, and Clostridioides difficile.
Natural infection with the influenza virus is believed to generate cross-protective immunity across both types and subtypes. However, less is known about the persistence of this immunity and thus the susceptibility of individuals to repeat infection. We used 13 years (2005–2017) of surveillance data from Queensland, Australia, to describe the incidence and distribution of repeat influenza infections. Consecutive infections that occurred within 14 days of prior infection were considered a mixed infection; those that occurred more than 14 days later were considered separate (repeat) infections. Kaplan-Meier plots were used to investigate the probability of reinfection over time and the Prentice, Williams and Peterson extension of the Cox proportional hazards model was used to assess the association of age and gender with reinfection. Among the 188 392 notifications received during 2005–2017, 6165 were consecutively notified for the same individual (3.3% of notifications), and 2958 were mixed infections (1.6%). Overall, the probability of reinfection was low: the cumulative incidence was <1% after one year, 4.6% after five years, and 9.6% after ten years. The majority of consecutive infections were the result of two type A infections (43%) and were most common among females (adjusted hazard ratio (aHR): 1.15, 95% confidence interval (CI) 1.09–1.21), children aged less than 5 years (relative to adults aged 18–64 years aHR: 1.58, 95% CI 1.47–1.70) and older adults aged at least 65 years (aHR: 1.35; 95% CI 1.24–1.47). Our study suggests consecutive infections are possible but rare. These findings have implications for our understanding of population immunity to influenza.
The impact of influenza and pneumonia on individuals in clinical risk groups in England has not previously been well characterized. Using nationally representative linked databases (Clinical Practice Research Database (CPRD), Hospital Episode Statistics (HES) and Office for National Statistics (ONS)), we conducted a retrospective cohort study among adults (≥ 18 years) during the 2010/2011–2019/2020 influenza seasons to estimate the incidence of influenza- and pneumonia-diagnosed medical events (general practitioner (GP) diagnoses, hospitalisations and deaths), stratified by age and risk conditions. The study population included a seasonal average of 7.2 million individuals; approximately 32% had ≥1 risk condition, 42% of whom received seasonal influenza vaccines. Medical event incidence rates increased with age, with ~1% of adults aged ≥75 years hospitalized for influenza/pneumonia annually. Among individuals with vs. without risk conditions, GP diagnoses occurred 2–5-fold more frequently and hospitalisations were 7–10-fold more common. Among those with obesity, respiratory, kidney or cardiovascular disorders, hospitalisation were 5–40-fold more common than in individuals with no risk conditions. Though these findings likely underestimate the full burden of influenza, they emphasize the concentration of disease burden in specific age and risk groups and support existing recommendations for influenza vaccination.
Influenza virus infections can lead to a number of secondary complications, including sepsis. We applied linear regression models to mortality and hospital admission data coded for septicaemia from 1998 to 2019 in Hong Kong, and estimated that septicaemia was associated with an annual average excess mortality rate of 0.23 (95% CI 0.04–0.40) per 100 000 persons per year and an excess septicaemia hospitalisation rate of 1.73 (95% CI 0.94–2.50) per 100 000 persons per year. The highest excess morbidity and mortality was found in older adults and young children, and during influenza A(H3N2) epidemics.
There is limited information on the volume of antibiotic prescribing that is influenza-associated, resulting from influenza infections and their complications (such as streptococcal pharyngitis and otitis media). Here, we estimated age/diagnosis-specific proportions of antibiotic prescriptions (fills) for the Kaiser Permanente Northern California population during 2010–2018 that were influenza-associated. The proportion of influenza-associated antibiotic prescribing among all antibiotic prescribing was higher in children aged 5–17 years compared to children aged under 5 years, ranging from 1.4% [95% CI (0.7–2.1)] in aged <1 year to 2.7% (1.9–3.4) in aged 15–17 years. For adults aged over 20 years, the proportion of influenza-associated antibiotic prescribing among all antibiotic prescribing was lower, ranging from 0.7% (0.5–1) for aged 25–29 years to 1.6% (1.2–1.9) for aged 60–64 years. Most of the influenza-associated antibiotic prescribing in children aged under 10 years was for ear infections, while for age groups over 25 years, 45–84% of influenza-associated antibiotic prescribing was for respiratory diagnoses without a bacterial indication. This suggests a modest benefit of increasing influenza vaccination coverage for reducing antibiotic prescribing, as well as the potential benefit of other measures to reduce unnecessary antibiotic prescribing for respiratory diagnoses with no bacterial indication in persons aged over 25 years, both of which may further contribute to the mitigation of antimicrobial resistance.
This study was performed to assess whether an intervention for critically appraising influenza vaccine exemption requests from healthcare personnel (HCP) affected (1) the overall rate of influenza vaccine exemption within a healthcare institution and/or (2) the rates of postintervention vaccine acceptance among those who inconsistently request exemption from annual vaccination and those who consistently request exemption from vaccination.
We conducted the study at a single academic medical center.
This study included 29,663 HCP.
Between 2010 and 2019, HCP were permitted to request an exemption from influenza vaccination without critical appraisal of exemption requests. After January 2019, medical center policy required critical appraisal of exemption requests. Of those employed 3 or more years who requested an exemption at least once during the preintervention period (n = 1,177), those with unchanging exemption reasons annually were termed “consistent exempters.” Those who changed reasons or accepted vaccination n ≥ 1 times were termed “inconsistent exempters.”
The overall exemption rate from influenza vaccine decreased from 3.8% to 1.2% (P < .001; N = 29,663) after the intervention. Of those requesting exemption at least once before the intervention, 329 (28.0%) of 1,177 were consistent exempters and 878 (72.0%) were inconsistent exempters. Of inconsistent exempters employed after the intervention, 442 (88.9%) of 497 accepted vaccine postintervention compared with 118 (59.6%) of 198 consistent exempters (P < .001). Of all exempters who changed from exemption to acceptance after the intervention, 442 (78.9%) of 560 were inconsistent exempters.
Critical appraisal of HCP exemption requests promotes influenza vaccine acceptance, and acceptance by inconsistent exempters drives the effect of the intervention. Analysis of changes in annual exemption requests represents a novel objective method for describing those on the spectrum of vaccine hesitancy.
The 2016–17 European outbreak of H5N8 HPAIV (Clade 22.214.171.124b) affected a wider range of avian species than the previous H5N8 outbreak (2014–15), including an incursion of H5N8 HPAIV into gamebirds in England. Natural infection of captive-reared pheasants (Phasianus colchicus) led to variable disease presentation; clinical signs included ruffled feathers, reluctance to move, bright green faeces, and/or sudden mortality. Several birds exhibited neurological signs (nystagmus, torticollis, ataxia). Birds exhibiting even mild clinical signs maintained substantial levels of virus replication and shedding, with preferential shedding via the oropharyngeal route. Gross pathology was consistent with HPAIV, in gallinaceous species but diphtheroid plaques in oropharyngeal mucosa associated with necrotising stomatitis were novel but consistent findings. However, minimal or modest microscopic pathological lesions were detected despite the systemic dissemination of the virus. Serology results indicated differences in the timeframe of exposure for each case (n = 3). This supported epidemiological conclusions confirming that the movement of birds between sites and other standard husbandry practices with limited hygiene involved in pheasant rearing (including several fomite pathways) contributed to virus spread between premises.
Acute myocarditis is a rare but potentially fatal disease. Endomyocardial biopsy and histologic examination are key to an accurate diagnosis. Despite being an uncommon cause, Influenza A and B viruses are a well-documented aetiology. Myocarditis may complicate about 0 to 10% of influenza virus infections (0.4 to 5% in paediatric cases). The clinical presentation varies widely, from ischemic-like chest pain to fulminant myocarditis with acute hemodynamic compromise, requiring mechanical circulatory support, with high mortality in the acute phase. We report a series of paediatric patients with myocarditis due to Influenza virus, to emphasize the importance of considering this uncommon aetiology.
The corona virus disease-2019 (COVID-19) pandemic began in Wuhan, China, and quickly spread around the world. The pandemic overlapped with two consecutive influenza seasons (2019/2020 and 2020/2021). This provided the opportunity to study community circulation of influenza viruses and severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in outpatients with acute respiratory infections during these two seasons within the Bavarian Influenza Sentinel (BIS) in Bavaria, Germany. From September to March, oropharyngeal swabs collected at BIS were analysed for influenza viruses and SARS-CoV-2 by real-time polymerase chain reaction. In BIS 2019/2020, 1376 swabs were tested for influenza viruses. The average positive rate was 37.6%, with a maximum of over 60% (in January). The predominant influenza viruses were Influenza A(H1N1)pdm09 (n = 202), Influenza A(H3N2) (n = 144) and Influenza B Victoria lineage (n = 129). In all, 610 of these BIS swabs contained sufficient material to retrospectively test for SARS-CoV-2. SARS-CoV-2 RNA was not detectable in any of these swabs. In BIS 2020/2021, 470 swabs were tested for influenza viruses and 457 for SARS-CoV-2. Only three swabs (0.6%) were positive for Influenza, while SARS-CoV-2 was found in 30 swabs (6.6%). We showed that no circulation of SARS-CoV-2 was detectable in BIS during the 2019/2020 influenza season, while virtually no influenza viruses were found in BIS 2020/2021 during the COVID-19 pandemic.
Little is known about respiratory viruses infection in Guinea. Influenza surveillance has not been implemented in Guinea mainly because of the paucity of laboratory infrastructure and capacity. This paper presents the first influenza surveillance data in Guinea.
Swabs were obtained from August 2018 through December 2019 at influenza sentinel sites and transported to the Institut National de Santé Publique for testing. Ribonucleic acid was extracted and tested for the presence of influenza A and B by real-time reverse transcription-polymerase chain reaction (RT-PCR). Positive samples were further characterised to determine the subtypes and lineages of influenza viruses.
A total of 862 swabs were collected and tested. Twenty-three per cent of samples tested positive for influenza A and B viruses. Characterisation of positive specimens identified influenza A/H1N1pmd09 (2.5%), influenza A/H3N2 (57.3%), influenza B/Victoria lineage (36.7%) and 7 (3.5%) influenza B with undetermined lineage. Influenza B virus activity clustered in August through November while influenza A/H3N2 displayed two clusters of activities that appeared in May through August and November through December.
For the first time in Guinea, the epidemiology, diversity and period of circulation of influenza viruses were studied. The results indicate the predominance and the periods of activities of influenza B Victoria lineage and influenza A/H3N2 which are important information for preventive strategies. It is warranted to extend the influenza surveillance to other parts of Guinea to better understand the epidemiology of the viruses and monitor the emergence of influenza strains with pandemic potential.
COVID-19 raises serious concerns regarding its unknown consequences for health, including psychiatric long term outcomes. Historically, influenza virus has been responsible for pandemics associated with schizophrenia. Epidemiological studies showed increased risk for schizophrenia in children of mothers exposed to the 1957 influenza A2 pandemic. Controversy remains concerning the mechanisms of pathogenesis underlying this risk.
We aim to review the evidence for the association between influenza infection and schizophrenia risk, the possible pathogenic mechanisms underlying and correlate these findings with the schizophrenia hypothesis of neurodevelopment.
We reviewed literature regarding evidence from epidemiological, translational animal models and serological studies using medline database.
The biological mechanisms likely to be relevant account to the effects of infection-induced maternal immune activation, microglial activation, infection-induced neuronal autoimmunity, molecular mimicry of the influenza virus, neuronal surface autoantibodies and psychosis with potential infectious antecedents. Influenza infection may fit into the theory of the neurodevelopment of schizophrenia as a factor that alters the normal maturation processes of the brain (possible second or third hit).
Influenza infection has multiple pathogenic pathways in both pre and post natal processes that might increase the risk of schizophrenia or psychosis. The existing evidence regarding the relationship between influenza virus and psychosis might help us draw similar long-term concerns of COVID-19.
Influenza vaccination remains the most effective primary prevention strategy for seasonal influenza. This research explores the percentage of emergency medical services (EMS) clinicians who received the seasonal flu vaccine in a given year, along with their reasons for vaccine acceptance and potential barriers.
A survey was distributed to all EMS clinicians in Virginia during the 2018-2019 influenza season. The primary outcome was vaccination status. Secondary outcomes were attitudes and perceptions toward influenza vaccination, along with patient care behaviors when treating an influenza patient.
Ultimately, 2796 EMS clinicians throughout Virginia completed the survey sufficiently for analysis. Participants were mean 43.5 y old, 60.7% male, and included the full range of certifications. Overall, 79.4% of surveyed EMS clinicians received a seasonal flu vaccine, 74% had previously had the flu, and 18% subjectively reported previous side effects from the flu vaccine. Overall, 54% of respondents believed their agency has influenza or respiratory specific plans or procedures.
In a large, state-wide survey of EMS clinicians, overall influenza vaccination coverage was 79.4%. Understanding the underlying beliefs of EMS clinicians remains a critical priority for protecting these frontline clinicians. Agencies should consider practical policies, such as on-duty vaccination, to increase uptake.
To describe school district preparedness for school closures and other relevant strategies before the coronavirus disease 2019 (COVID-19) pandemic.
A stratified random sample of 957 public school districts from the 50 US states and the District of Columbia were surveyed between October 2015 and August 2016. The response rates for the questionnaires were as follows: Healthy and Safe School Environment, Crisis Preparedness Module (60%; N = 572), Nutrition Services (63%; N = 599), and Health Services (64%; N = 613). Data were analyzed using descriptive and regression techniques.
Most school districts had procedures that would facilitate the implementation of school closures (88.7%). Fewer districts had plans for ensuring continuity of education (43.0%) or feeding students during closure (33.8%). The prevalence of continuity of education plans was lower in the Midwest than the Northeast (adjusted prevalence ratio [aPR] = 0.68; 95% confidence interval [CI]: 0.51-0.90). Presence of plans for feeding students was higher in high-poverty than low-poverty districts (aPR = 1.41; 95% CI: 1.01-1.99) and in large districts than small districts (aPR = 2.06; 95% CI: 1.37-3.09).
Understanding factors associated with having comprehensive emergency plans could help decision makers to target assistance during the current COVID-19 pandemic and for future planning purposes.