Annual Influenza Vaccination Research Articles

Financial incentives tied to Medicare star ratings: impact on influenza vaccination uptake in Medicare beneficiaries.

To evaluate the impact of the star rating bonus payment policy on annual influenza vaccination rates before and after the policy was adopted for Medicare Advantage (MA) plans in 2012. Observational study using data from the Medicare Current Beneficiary Survey from 2007 to 2015 to test whether the bonus payment policy led to higher flu vaccination rates in MA prescription drug (MAPD) plans vs fee-for-service prescription drug plans (PDPs), which were ineligible for bonus payments. Mean preperiod (2007-2011) and postperiod (2012-2015) influenza vaccination rates were compared for enrollees in both types of plans using descriptive and multivariate difference-in-difference (DID) equations. The experimental effect of the MA bonus payment policy was estimated as the interaction between plan type (MAPD plan vs PDP) and period (pre- vs post period) controlling for the main effects of plan type (MAPD vs PDP), timing of the observation (pre- vs post period), and other potential confounders. The study sample included 40,369 person-years of data in the preperiod and 27,703 person-years of data in the post period. Vaccination rates increased by 3.8% in MAPD plans compared with 2.7% in PDPs, leading to a relative MAPD-favored difference that was nonsignificant (P = .31). However, the effect was statistically significant (odds ratio [OR], 1.12; P = .03) in the main multivariate DID model. A larger relative difference was observed among beneficiaries 75 years and older (OR, 1.18; P = .03). The Medicare bonus payment policy led to a small increase in beneficiaries' flu vaccination rates, suggesting that expanding the star measure set could be an effective way to increase uptake for other recommended adult vaccines.

Predictors of Influenza Vaccination Uptake and the Role of Health Literacy among Health and Social Care Volunteers in the Province of Prato (Italy).

Annual influenza vaccination is recommended for volunteers involved in primary health and social services. Little is known about the volunteers’ adhesion to influenza vaccination recommendations. The aim of this study was to assess influenza vaccination determinants among a group of volunteers who provided essential activities during the first SARS-CoV-2 pandemic wave in the province of Prato, Tuscany (Italy) and to evaluate the role of health literacy in influencing vaccination determinants. Method: In this cross-sectional study, the predictors of influenza vaccination uptake were assessed through the administration of a questionnaire. Variables significantly associated with influenza vaccination uptake were included in five multivariate logistic regression models through a backward stepwise procedure. Results: Among the 502 enrolled volunteers, 24.3% reported being vaccinated in the 2019–2020 season. Vaccination uptake was 48.8% in participants aged 65 years or older and 15.7% in those aged 64 years or younger. Considering the whole sample in the final model of multivariate logistic regression analysis, the predictors of influenza vaccination uptake were age (OR = 1.05; 95% CI = 1.03–1.07), presence of heart diseases (OR = 2.98; 95% CI = 1.24–7.19), pulmonary diseases (OR = 6.18; 95% CI = 2.01–19.04) and having undergone surgery under general anesthesia in the prior year (OR = 3.14; 95% CI = 1.23–8.06). In the multivariate model considering only participants with a sufficient level of health literacy (HL), none of these predictors resulted in significant associations with vaccination uptake, except for age (OR= 1.04; 95% CI = 1.02–1.07). Conclusions: Our findings revealed a very low influenza vaccination uptake among volunteers, suggesting the need to increase awareness in this at-risk group by means of a better communication approach.

Seasonal Influenza Vaccination at a German University Hospital: Distinguishing Barriers Between Occupational Groups.

The annual influenza vaccination has been officially recommended for medical staff in Germany since 1988. Nevertheless, the vaccination rate among medical staff is still low. The present study deals with the influenza vaccination rate of staff at a German University hospital over time as well as with the reasons that led to a positive vaccination decision and the barriers to acceptance of vaccination. For this purpose, the staff members received questionnaires in which they were asked about influenza vaccination and the reasons for or against vaccination. In addition, the questionnaire contains information on gender, age group, occupational group and presence of a chronic co-morbidity. Logistic regression analysis was used to investigate which of these predictors most strongly influenced the vaccination decision. It was shown that the reasons for or against vaccination differ significantly between the occupational groups and that the occupational group affiliation has the greatest influence on the vaccination decision in the comparison of the investigated predictors. In order to achieve a positive influence on vaccination acceptance, future measures should focus on increasing confidence in vaccination and on increasing the perception of risk from influenza illness. The findings may contribute to future targeted strategies to increase vaccination rates and suggest occupational group-specific interventions.

Editor's Spotlight/Take 5: Discussing Two Systematic Reviews With Opposing Conclusions on Shoulder Pain After Vaccine Administration.

Editor's Spotlight/Take 5: Discussing Two Systematic Reviews With Opposing Conclusions on Shoulder Pain After Vaccine Administration.

High seroprotection rates and geometric mean titre increases after repeated annual influenza vaccinations in a cohort of HIV-infected adults in Austria

IntroductionVaccination against seasonal influenza is recommended for all HIV-infected persons. Few data have been reported on the effect of repeated annual vaccination in this population. MethodsWe measured haemagglutination inhibition antibody responses and investigated seroprotection rates in 344 HIV-infected adults before and 12 weeks after influenza vaccination with a trivalent subunit vaccine. Results68.3% of patients were male, the median age was 45 years. 83.7% had a viral load < 50 copies/mL. The median CD4 count was 604/µL. 304 patients (88.4%) had received influenza vaccinations in previous years. Seroprotection rates for A/H1N1 and B were over 90% in all age groups before vaccination and close to 100% after vaccination. For A/H3N2, seroprotection rates were lowest in individuals below 30 years both before and after vaccination (22.2% and 50.0%) and higher in older age groups (48.4% and 83.9% in people over 60 years). GMT fold increases were not significantly different across the age groups (3.0 to 4.2, p = 0.425). Previous influenza vaccinations were associated with higher seroprotection rates before and after vaccination (62.2% and 84.2% in patients with 8 or more previous vaccinations vs. 15.0% and 57.5% without previous vaccinations, respectively). Individuals with detectable viral load, elevated immune activation (urine neopterin ≥ 250 µmol/mol creatinine), and higher CD4 nadir (≥200 cells/µL) showed a trend towards inferior immune responses to vaccination, whereas gender and CD4 count did not have an effect. ConclusionThe lower seroprotection rates observed in younger individuals may be explained by the higher proportion of patients without HIV treatment and with fewer previous encounters with influenza strains. Good seroprotection rates can be achieved in elderly HIV-infected patients and after repeated annual vaccinations.

Live-attenuated influenza vaccine effectiveness against hospitalization in children aged 2-6years, the first three seasons of the childhood influenza vaccination program in England, 2013/14-2015/16.

IntroductionIn 2013, the United Kingdom began to roll‐out a universal annual influenza vaccination program for children. An important component of any new vaccination program is measuring its effectiveness. Live‐attenuated influenza vaccines (LAIVs) have since shown mixed results with vaccine effectiveness (VE) varying across seasons and countries elsewhere. This study aims to assess the effectiveness of influenza vaccination in children against severe disease during the first three seasons of the LAIV program in England.MethodsUsing the screening method, LAIV vaccination coverage in children hospitalized with laboratory‐confirmed influenza infection was compared with vaccination coverage in 2–6‐year‐olds in the general population to estimate VE in 2013/14–2015/16.ResultsThe overall LAIV VE, adjusted for age group, week/month and geographical area, for all influenza types pooled over the three influenza seasons was 50.1% (95% confidence interval [CI] 31.2, 63.8). By age, there was evidence of protection against hospitalization from influenza vaccination in both the pre‐school (2–4‐year‐olds) (48.1%, 95% CI 27.2, 63.1) and school‐aged children (5–6‐year‐olds) (62.6%, 95% CI 2.6, 85.6) over the three seasons.ConclusionLAIV vaccination in children provided moderate annual protection against laboratory‐confirmed influenza‐related hospitalization in England over the three influenza seasons. This study contributes further to the limited literature to date on influenza VE against severe disease in children.

Adult Vaccination as a Protective Factor for Dementia: A Meta-Analysis and Systematic Review of Population-Based Observational Studies.

BackgroundCommon vaccinations may have impacts on dementia risk, but current evidence is inconsistent. We therefore investigated the association between vaccinations and dementia risk by systematic review and meta-analysis approach.MethodsWe conducted an extensive search of PubMed, Embase, Cochrane Library, and Web of Science to identify studies that compared the risk of dementia in vaccinated versus unvaccinated populations. The adjusted hazard ratio (HR) and corresponding 95% confidence intervals (CIs) were pooled as measures.ResultsOf the 9124 records initially retrieved, 17 studies with 1857134 participants were included in our analysis. The overall pooled results showed that vaccinations were associated with a 35% lower dementia risk (HR=0.65, 95% CI: 0.60-0.71, P overall effect < 0.001; I2 = 91.8%, P heterogeneity<0.001). All types of vaccination were associated with a trend toward reduced dementia risk, with rabies (HR=0.43), tetanus & diphtheria & pertussis (Tdap) (HR=0.69), herpes zoster (HR=0.69), influenza (HR=0.74), hepatitis A (HR=0.78), typhoid (HR=0.80), and hepatitis B (HR=0.82) vaccinations being significant. Individuals with more full vaccination types and more annual influenza vaccinations were less likely to develop dementia. Gender and age had no effect on this association.ConclusionRoutine adult vaccinations are associated with a significant reduction in dementia risk and may be an effective strategy for dementia prevention. Further research is needed to elucidate the causal effects of this association and the underlying mechanisms.

Sex differences in B cell frequencies and antibody responses following influenza vaccination in healthcare workers during the 2019–2020 season

Abstract Annual influenza vaccination for healthcare workers (HCWs) is required at Johns Hopkins to reduce influenza spread in healthcare facilities. We conducted a clinical study to evaluate sex differences in virus-specific antibody-producing B cells (i.e., plasmablasts) following receipt of the seasonal influenza vaccine in a highly vaccinated population of healthcare workers. To understand sex differences in immune responses to the influenza vaccine in the HCWs, 83 participants consented to blood draws at baseline and 75 participants returned for the 7- and 28-days post-vaccination survey and blood draw. Participants received their annual quadrivalent influenza vaccine (QIV). Influenza A specific plasmablasts were quantified at baseline and day 7 post-vaccination. Males had a significantly greater percentage of influenza-specific plasmablasts than females after vaccination (p&amp;lt;0.0003) Plasma collected at baseline and at day 28 post-vaccination was used to measure neutralizing antibody (nAb) titers against H1N1 and H3N2 vaccine viruses. Neutralizing antibody responses against either the H1N1 and H3N2 viruses increase after vaccination to the same degree in both males and females. The proportion of plasmablasts at day 7 was significantly associated with the vaccine-induced fold rise in nAb. This relationship differed by sex, whereby for a given proportion of plasmablasts, females tended to mount a greater fold-rise in nAb than males. These data suggest that despite having potentially fewer plasmablasts after vaccination, females mount an antiviral antibody response to the influenza vaccine viruses equivalent to males. Identification of transcriptional differences in plasmablasts from male and female HCWs is ongoing.

Consistency of self-reported and documented historical influenza vaccination status of US healthcare workers.

BackgroundHealthcare personnel (HCP) are a priority group for annual influenza vaccination. Few studies have assessed the validity of recall of prior influenza vaccination status among HCP, especially for more than one preceding season.MethodsUsing data from a randomized controlled trial of influenza vaccination among 947 HCP from two US healthcare systems, we assessed agreement between participant self‐report and administrative record documentation of influenza vaccination status during the preceding five influenza seasons; kappa coefficients and sensitivity values were calculated. Administrative record documentation was considered the gold standard. Documented vaccination sources included electronic medical records, employee health records, outside immunization providers, and the state immunization information system.ResultsAmong 683 HCP with prior influenza immunization information, 89.7% (95% CI: 87.2%, 91.9%) of HCP were able to self‐report their vaccination status for the season preceding the survey. By the fifth preceding season, 82.6% (95% CI: 79.5%, 85.3%) of HCP were able to self‐report. Among HCP who self‐reported their vaccination status, agreement between self‐report and documented vaccination status ranged from 81.9% (95% CI: 77.2%, 86.7%) for the fifth season to 90.5% (95% CI: 87.2%, 93.9%) for the season preceding interview. HCP who received vaccine for only some of the preceding five seasons (18.3%) more commonly had ≥2 errors in their recall compared with those vaccinated all five preceding seasons (55.7% vs. 4.3%).ConclusionsSelf‐reported vaccination status is a reliable source for historical influenza vaccination information among HCP who are consistently vaccinated but less reliable for those with a history of inconsistent vaccination.

Influenza Vaccination Rates, and Barriers to Influenza Vaccination, in People who are Homeless

Background: Influenza is a highly infectious virus which is endemic in most high-income countries. People experiencing homelessness are at an increased risk of contracting influenza, and often have poorer outcomes associated with hospitalisation and mortality. Annual influenza vaccination is recommended for all adults, and highly recommended for ‘at-risk’ groups, including people who are homeless. Despite this, the vaccination uptake within the homeless community is low. This systematic review will identify influenza vaccination rates, and barriers to influenza vaccination, in people who are homeless.&#x0D; &#x0D; Methods: This review will consider primary studies about influenza vaccination in people who are homeless. Searches will be undertaken on five electronic databases and managed in EndNote X9. The literature will be screened by title/abstract, then by full-text, and citation chaining will be completed. Data about the influenza vaccination rates and barriers will be extracted. Each task, primarily the screening and extraction of data, will be completed by one researcher, and checked by at least one other.&#x0D; &#x0D; &#x0D; Discussion: This review will identify influenza vaccination rates, and barriers to influenza vaccination, in people experiencing homelessness. This will inform vaccination delivery and funding, and may contribute to reducing the health disparities in this at-risk, hard-to-reach population.

The New Quadrivalent Adjuvanted Influenza Vaccine for the Italian Elderly: A Health Technology Assessment.

Background. The elderly, commonly defined as subjects aged ≥65 years, are among the at-risk subjects recommended for annual influenza vaccination in European countries. Currently, two new vaccines are available for this population: the MF59-adjuvanted quadrivalent influenza vaccine (aQIV) and the high-dose quadrivalent influenza vaccine (hdQIV). Their multidimensional assessment might maximize the results in terms of achievable health benefits. Therefore, we carried out a Health Technology Assessment (HTA) of the aQIV by adopting a multidisciplinary policy-oriented approach to evaluate clinical, economic, organizational, and ethical implications for the Italian elderly. Methods. A HTA was conducted in 2020 to analyze influenza burden; characteristics, efficacy, and safety of aQIV and other available vaccines for the elderly; cost-effectiveness of aQIV; and related organizational and ethical implications. Comprehensive literature reviews/analyses were performed, and a transmission model was developed in order to address the above issues. Results. In Italy, the influenza burden on the elderly is high and from 77.7% to 96.1% of influenza-related deaths occur in the elderly. All available vaccines are effective and safe; however, aQIV, such as the adjuvanted trivalent influenza vaccine (aTIV), has proved more immunogenic and effective in the elderly. From the third payer’s perspective, but also from the societal one, the use of aQIV in comparison with egg-based standard QIV (eQIV) in the elderly population is cost-effective. The appropriateness of the use of available vaccines as well as citizens’ knowledge and attitudes remain a challenge for a successful vaccination campaign. Conclusions. The results of this project provide decision-makers with important evidence on the aQIV and support with scientific evidence on the appropriate use of vaccines in the elderly.

COVID-19 vaccine hesitancy and missed vaccine roll- out targets: The case for using general practitioners

The South African (SA) government’s roll-out of the COVID-19 vaccine is behind its target, largely owing to concerns about the sideeffects and the effectiveness of the vaccines, and because they have been developed over a very short time frame. Another factor is a lack of trust in government policies regarding COVID-19 and its running of public health. One survey has indicated that for persons seeking a vaccination, the preferred vaccine site would be general practitioners (GPs). GPs have been used in Australia, the UK and elsewhere. In Australia, with a scattered rural population, 5 600 GPs have been vaccinating over one million patients weekly. Calls have been made by the South African Medical Association, among others, for GPs to be allowed to assist with the government’s roll-out programme. If ~8 000 GPs in SA participated in a properly administered roll-out programme, and each GP were to vaccinate only 10 people a day, this would yield 400 000 vaccinations a week or ~1.6 million a month. The GPs could invite their patients and others to visit their room for a COVID-19 vaccination, as they do with the annual influenza vaccine.

Recommended Adult Immunization Schedule, United States, 2022.

Recommended Adult Immunization Schedule, United States, 2022.

Social determinants of health and adult influenza vaccination: a nationwide claims analysis.

BACKGROUND: The health and economic benefits of the annual influenza vaccine are well documented, yet vaccination rates in the United States missed the Healthy People 2020 goal and remain a focus of Healthy People 2030 efforts. By identifying underlying reasons for low annual influenza vaccination, social elements that need targeting may be identified and could guide future interventions or policy development to achieve vaccination goals and improve overall public health. OBJECTIVE: To determine the influence of certain social determinants of health on adherence to annual influenza vaccination in American adults. METHODS: This was a retrospective cohort analysis using data from IBM MarketScan Commercial Claims and Encounters Database and national Medicare 5% sample data from 2013 to 2016. Study eligibility criteria included adults (aged 18 years and older) who were continuously enrolled for 3 influenza seasons between 2013 and 2016. Receipt of the influenza vaccine was counted over 3 consecutive influenza seasons, and select social determinants were extracted from publicly available sources. Patient characteristics, health resource utilization, and selected social determinants of health were included in bivariate and multivariate logistic regression analyses to determine their association with annual influenza vaccination. RESULTS: 6,694,571 adults across employer-sponsored and Medicare coverage groups were analyzed, of which 14.7% of Medicare-enrolled adults and 9.2% of commercially enrolled adults were vaccinated in all 3 seasons. Higher proportions of vaccine adherence (ie, all 3 seasons) were observed among females (9.6% vs 8.7% [commercial], 15.0% vs 14.4% [Medicare]), the immunocompromised (11.8% vs 8.3% [commercial], 15.9% vs 13.6% [Medicare]), rural residents (10.5% vs 9.0% [commercial], 15.4% vs 14.6% [Medicare]; all P < 0.0001), and those enrolled in a high-deductible health plan (10.3%). Multivariable logistic regression models indicated that the odds of vaccine adherence tended to be higher in areas of higher poverty (OR=1.012; 95% CI = 1.01-1.02 [commercial], OR=1.01; 95% CI = 1.01-1.01 [Medicare]) yet lower in areas with higher proportions of Democratic voters (OR=0.998; 95% CI = 0.998-0.998 [commercial], OR = 0.996; 95% CI = 0.996-0.997 [Medicare]). Among commercially insured adults, the odds of vaccine adherence were higher in areas of higher health literacy (OR=1.036; 95% CI = 1.036-1.037), but this effect was not observed among Medicare members. Conversely, the odds of vaccine adherence increased as the proportion of those residing in areas of limited Internet access increased (OR=1.007; 95% CI = 1.004-1.010) among Medicare members only. CONCLUSIONS: Key social determinants of health are important factors of vaccine adherence and can guide policy and intervention efforts toward addressing potential hesitancy. A deeper assessment of other contributing social factors is needed in seasonal influenza and other vaccines to better interpret the vaccine-seeking behaviors of adults. DISCLOSURES: This study received no outside funding. Gatwood, Hagemann, Hohmeier, and Chiu declare vaccine-related grant funding from Merck & Co. and GlaxoSmithKline for vaccine research unrelated to the current study. Ramachandran declares vaccine-related grant funding from Glaxo-SmithKline for research unrelated to the current study. Shuvo and Behal have nothing to disclose. Findings described in this study were presented as a poster and podium at the Academy of Managed Care Pharmacy Nexus 2020 Virtual meeting, October 19-23, 2020.

Effectiveness of influenza vaccination in the elderly: a population-based case-crossover study

BackgroundThere is limited information regarding the effectiveness of influenza vaccines for older adults. Particularly, controlling for healthy senior bias is challenging in observational studies. We aimed to assess the efficacy...

The cost-effectiveness of starting 23-valent pneumococcal polysaccharide vaccine and influenza vaccination at 50 vs. 65 years: A comparative modelling study

ObjectivesPneumococcal infection is a leading cause of morbidity and mortality. We aimed to evaluate the cost-effectiveness of 23-valent polysaccharide vaccine (PPV23) together with influenza vaccination or pneumococcal vaccination alone in adults starting from 50 years vs. 65 years in Hong Kong. MethodsA hypothetical population of 100,000 older adults was included in a Markov model with age ranging from 50 to 85 years to calculate the cost and quality-adjusted life-years (QALYs) gained for vaccination strategies, including: (1) annual influenza vaccine and PPV23 at 50 and 65 years; (2) annual influenza vaccine and PPV23 at 65 years (similar with the current vaccination programme); (3) PPV23 at 50 and 65 years; (4) PPV23 at 65 years; and (5) no vaccination. We evaluated the incremental cost-effectiveness ratio (ICER) and used Monte Carlo simulation for probabilistic sensitivity analysis. The cost-effectiveness threshold was extracted from previous literature. ResultsIn comparison with no vaccination, all strategies were cost-effective with ICERs less than the threshold (US$24,302 per QALY gained). When compared with no vaccination, strategies 1–4 saved US$ 49.5, US$ 94.9, US$ 584.3, and US$ 1114.2 to gain one QALY respectively. In comparison with strategy 2, strategy 1 spent US$ 195.3 to gain one QALY, whilst strategies 3 and 4 showed less effectiveness with increased costs. ConclusionsAll vaccination strategies were cost-effective, among which the strategy of PPV23 at 50/65 years with annual influenza vaccine was cost-effective even in comparison with current vaccination programme. These findings could help inform the design and implementation of vaccination strategies.

National FluWatch mid-season report, 2021-2022: Sporadic influenza activity returns.

Surveillance for Canada's 2021-2022 seasonal influenza epidemic began in epidemiological week 35 (the week starting August 29, 2021) during the ongoing coronavirus disease 2019 (COVID-19) global public health emergency. In the 2021-2022 surveillance season to date, there has been a return of persistent sporadic influenza activity, and the first influenza-associated hospitalizations since mid-2020 have been reported. However, as of week 52 (week ending 01/01/2022) activity has remained sporadic, and no influenza-confirmed outbreaks or epidemic activity have been detected. There has been a delay or absence in several traditional seasonal influenza milestones, including the declared start of the influenza season, marked by a threshold of 5% positivity, which historically has occurred on average in week 47. The 429 sporadic detections reported in Canada to date have occurred in 31 regions across seven provinces/territories. Nearly half (n=155/335, 46.3%) of reported cases have been in the paediatric (younger than 19 years) population. Three-quarters of the cases were influenza A detections (n=323/429, 75.3%). Of the subtyped influenza A detections, A(H3N2) predominated (n=83/86, 96.5%). Of the 12 viruses characterized by the National Microbiology Laboratory, 11 were seasonal strains. Among the seasonal strains characterized, only one was antigenically similar to the strains recommended for the 2021-2022 Northern Hemisphere vaccine, though all were sensitive to the antivirals, oseltamivir and zanamivir. Until very recently, seasonal influenza epidemics had not been reported since March 2020. Evidence on the re-emergence of seasonal influenza strains in Canada following the A(H1N1)pdm09 pandemic shows that influenza A(H3N2) and B epidemics ceased through the 2009-2010 season and second wave of A(H1N1)pdm09, but then re-emerged in subsequent seasons to predominate causing epidemics of higher intensity than in the pre-pandemic seasons. When and where seasonal influenza epidemic activity resumes cannot be predicted, but model-based estimates and historical post-pandemic patterns of intensified epidemics warrant continued vigilance through the usual season and for out-of-season re-emergence. In addition, ongoing population preparedness measures, such as annual influenza vaccination to mitigate the intensity and burden of future seasonal influenza epidemic waves, should continue.

Exploring strategies to increase college students’ motivation to receive their annual influenza vaccine

Objective To evaluate college students’ awareness of an educational initiative to increase campus influenza vaccination rates and strategies to improve it. Participants Students attending a large public comprehensive university. Methods An investigator-developed, online survey evaluated awareness of the initiative, the students’ perception of incentives, and other motivations to receive seasonal influenza vaccine. Results The vaccination rate was 43%, despite low awareness of the initiative (28%). Awareness was significantly higher among vaccinated students (p = 0.0013). Having knowledge that appointments to receive vaccine were not needed increased the motivation of vaccinated students more than unvaccinated students (p = 0.0001). Personal influencers increased motivation of vaccinated students only when they were aware of the initiative (p = 0.04). Tangible incentives did not motivate students. Conclusions Campus vaccination rates increased despite low initiative awareness. Improvements to the initiative should include strategies to increase emphasis on vaccination program conveniences like accessibility and perhaps engage personal influencers more.

Performance of a Rapid Diagnostic Test for Influenza in a Tertiary Military Hospital, Philippines.

It is important to evaluate the performance of existing rapid influenza diagnostic tests (RIDTs) and the factors that can affect performance especially when the circulation dynamics of influenza strains change such as the displacement and replacement of the circulating seasonal influenza strains. Nasal swabs were collected from patients presenting at V Luna Medical Center, Armed Forces of the Philippines Health Service Command, with influenza-like illness (ILI) with one swab tested using Quickvue (QV) influenza A+B RIDT (Quidel) and the other swab tested using the ABI 7500 (Applied Biosystems) real-time reverse transcriptase-polymerase chain reaction. Sensitivity, specificity, positive predictive value, and negative predictive value were estimated. We identified clinical symptoms predictive of influenza subtype and evaluated the independence of QV sensitivity on (1) Cycle threshold (Ct) value, controlling for timing of collection; (2) timing of collection, controlling for Ct value; and (3) Ct value and timing of collection taken together. Between August 2011 and October 2016, patients presenting with ILI (n = 2333) underwent testing. Quickvue sensitivity across all subtypes was significantly correlated with lower Ct values (higher virus titers) (P <.001) and, except for flu A/H3 (P = .974), was also significantly associated with timing of specimen collection (P <.05). No statistically significant difference was noted in QV sensitivity for Flu A/H3 (P = .130), pandemic H1/N1 (P = .207), Flu A/H3 + pandemic H1/N1 (P = .341), and Flu B (P = .103) across different age groups but sensitivity of QV significantly differed (P <.001) across the different influenza subtypes. Overall specificity of QV was high across all flu subtypes, but overall sensitivity was low (Flu A/pdm H1) to moderate (Flu A/H3 and Flu B). The findings highlight the need to develop more sensitive influenza RDTs to detect circulating influenza strains and the use of the quadrivalent flu vaccine during the annual influenza vaccination.

Is there a role for inpatient influenza vaccination programmes?

Patients with chronic liver disease have much higher mortality associated with influenza compared to other risk groups (1). Influenza vaccine uptake is much lower in adults with chronic liver disease (37.3%) compared to adults aged over 65 (72.4%) or other risk groups (44.9%) (2). Hospital-based interventions for inpatients have been shown to increase uptake (3). Vaccination records of patients admitted to a Hepatology ward were reviewed retrospectively to understand what proportion were eligible but did not receive annual influenza vaccine through current services. Data was collected for inpatients 26th September 2020 to 29th November 2020. GP records were used to check vaccination status within the window 01/09/2020 to 28/02/2021. Patients not registered with a local GP or deceased were excluded. We compared the rates of vaccination between at risk groups. 134 were eligible for influenza vaccination and inclusion. 95 (70.9%) were not immunised at the time of admission. 36 (29.1%) went on to be immunised in the same influenza season, leaving 59 (44.0%) of individuals not receiving a vaccine at all. Vaccination rates are below the 75% target. Most patients, who were eligible at the time of admission, never received an influenza vaccination. An inpatient influenza vaccination programme could utilise this missed opportunity to increase vaccine uptake.