Effect of COVID-19 Pandemic on Invasive Pneumococcal Disease in Children, Catalonia, Spain.

We analyzed the effect of COVID-19 on healthcare demand and invasive pneumococcal disease in children in Catalonia, Spain. Compared with 2018-2019, we noted large reductions in healthcare activities and incidence of invasive pneumococcal disease in 2020. These changes likely resulted from nonpharmaceutical measures implemented during the COVID-19 pandemic.

Surveillance of influenza B severe hospitalized cases during 10 seasons in Catalonia: Does the lineage make a difference?

Influenza B viruses circulate in two lineages (B/Victoria and B/Yamagata). Although classically affecting children, recently it has shown a high rate of infection and increased hospitalization in the elderly. To describe and analyze the clinical and epidemiological characteristics of severe hospitalized laboratory-confirmed influenza B virus (SHLCI-B) cases in Catalonia associated with mismatch from Influenza B virus strain included in the trivalent influenza vaccine (TIV). SHLCI-B was registered by the influenza sentinel surveillance system of Catalonia (PIDIRAC) during ten surveillance seasons from 2010 to 2020. Variables age, comorbidities, and vaccination status were recorded. Vaccine effectiveness was estimated as (1-OR) for intensive care unit (ICU) admission. Statistical significance was established at p < 0.05. A total of 1159 SHLCI-B were registered, of these 68.2% (791) corresponded to the 2017-2018 season; 21.8% (253) were admitted to ICU and 13.8% (160) were exitus; 62.5% (725) cases occurred in those aged >64 years; most frequent risk factor was cardiovascular disease (35.1%, 407) followed by chronic pulmonary obstructive disease-COPD (24.6%, 285) and diabetes (24.1%, 279). In four seasons, the predominant circulating lineage was B/Victoria, in two seasons the B/Yamagata lineage and four seasons had no IBV activity. Four seasons presented discordance with the strain included within the TIV. Vaccine effectiveness (VE) to prevent ICU admission was 31% (95% confidence interval [CI]: 4%-51%; p = 0.03); being 29% (95% CI: -3% to 51%) in discordant and 43% (95% CI:-43% to 77%) in concordant seasons. Significant differences were observed in the number of affected aged > 64 years (odds ratio [OR] = 2.5; 95% CI: 1.9-3.4; p < 0.001) and in patients with heart disease (OR = 2.40 95% CI: 1.7-3.4; p < 0.001), COPD (OR = 1.6 95% CI: 1.1-2.3; p = 0.01), and diabetes (OR = 1.5 95% CI: 1.1-2.1; p = 0.04) between discordant and concordant seasons. The increase in hospitalization rate in people> 64 years of age and those presenting comorbidities in seasons with circulating influenza B virus belonging to a lineage discordant with the strain included in the TIV and the decrease of VE to prevent ICU admissions evidence the vital need to administer the quadrivalent influenza vaccine regardless of the findings of predominant circulation in the previous season.

Pro-vegetarian food patterns and cardiometabolic risk in the PREDIMED-Plus study: a cross-sectional baseline analysis.

PURPOSE: We explored the cross-sectional association between the adherence to three different provegetarian (PVG) food patterns defined as general (gPVG), healthful (hPVG) and unhealthful (uPVG), and the cardiometabolic risk in adults with metabolic syndrome (MetS) of the PREDIMED-Plus randomized intervention study. METHODS: We performed a cross-sectional analysis of baseline data from 6439 participants of the PREDIMED-Plus randomized intervention study. The gPVG food pattern was built by positively scoring plant foods (vegetables/fruits/legumes/grains/potatoes/nuts/olive oil) and negatively scoring, animal foods (meat and meat products/animal fats/eggs/fish and seafood/dairy products). The hPVG and uPVG were generated from the gPVG by adding four new food groups (tea and coffee/fruit juices/sugar-sweetened beverages/sweets and desserts), splitting grains and potatoes and scoring them differently. Multivariable-adjusted robust linear regression using MM-type estimator was used to assess the association between PVG food patterns and the standardized Metabolic Syndrome score (MetS z-score), a composed index that has been previously used to ascertain the cardiometabolic risk, adjusting for potential confounders. RESULTS: A higher adherence to the gPVG and hPVG was associated with lower cardiometabolic risk in multivariable models. The regression coefficients for 5th vs. 1st quintile were - 0.16 (95% CI: - 0.33 to 0.01) for gPVG (p trend: 0.015), and - 0.23 (95% CI: - 0.41 to - 0.05) for hPVG (p trend: 0.016). In contrast, a higher adherence to the uPVG was associated with higher cardiometabolic risk, 0.21 (95% CI: 0.04 to 0.38) (p trend: 0.019). CONCLUSION: Higher adherence to gPVG and hPVG food patterns was generally associated with lower cardiovascular risk, whereas higher adherence to uPVG was associated to higher cardiovascular risk.

Invasive Pneumococcal Disease and Influenza Activity in a Pediatric Population: Impact of PCV13 Vaccination in Pandemic and Nonpandemic Influenza Periods.

The objective of this study was to analyze the incidence, clinical presentation, and severity of invasive pneumococcal disease (IPD)-causing serotypes and the impact of the 13-valent pneumococcal conjugate vaccination during epidemic and nonepidemic influenza periods in Catalonia, Spain. This was a prospective study in persons aged <18 years diagnosed with IPD between 2012 and 2015 in three Catalan pediatric hospitals. IPD was defined as clinical infection together with isolation of Streptococcus pneumoniae by culture and/or detection by reverse transcription-PCR in a normally sterile sample. Incidence rate ratios (IRRs) and the fraction of IPD prevented associated with 13-valent pneumococcal conjugate vaccine (PCV13) were calculated. The bivariate analysis used the χ2 test and the multivariate analysis nonconditional logistic regression. A total of 229 cases of IPD were recorded. The incidence was higher during influenza epidemic periods (IRR, 2.7; 95% confidence interval [CI], 2.05 to 3.55; P < 0.001), especially for pneumonia (IRR, 3.25; 95% CI, 2.36 to 4.47; P < 0.001), with no differences in the distribution of pneumococcal serotypes. Complications during admission and sequel at discharge were greater during epidemic periods (adjusted odds ratio [aOR], 2.00; 95% CI, 1.06 to 3.77; P = 0.03) than at nonepidemic periods (aOR, 3.38; 95% CI, 1.37 to 8.29; P = 0.01). The prevented fraction for the population (PFp) of IPD in children aged 7 to 59 months was 48% to 49.4%. The PFp was higher in influenza epidemic than nonepidemic periods and increased when ≥2 doses of PCV13 or ≥1 after 24 months were administered. Influenza virus circulation increases the incidence of IPD in persons aged <18 years. In influenza epidemic periods, IPD cases were more severe. Increased PCV13 coverage might increase the fraction of IPD prevented in epidemic and nonepidemic periods.

Smoking may increase the risk of influenza hospitalization and reduce influenza vaccine effectiveness in the elderly.

Background: Through its effects on the immune system, smoking may facilitate influenza virus infection, its severity and its most frequent complications. The objective was to investigate the smoking history as a risk factor for influenza hospitalization and influenza vaccine effectiveness in elderly smokers/ex-smokers and non-smokers. Methods: We carried out a multicenter case-control study in the 2013-2014 and 2014-2015 influenza seasons. Cases aged ≥65 years and age-, sex-matched controls were selected from 20 Spanish hospitals. We collected epidemiological variables, comorbidities, vaccination history and the smoking history. The risk of hospitalization due to smoking (current smokers and ex-smokers) was determined using the adjusted odds ratio (aOR) with conditional logistic regression models. Vaccine effectiveness (VE) was calculated using the formula: VE = (1 - aOR) × 100. Results: We studied 728 cases and 1826 controls. Cases had a higher frequency of smoking (47.4% vs 42.1%). Smoking was associated with an increased risk of influenza hospitalization (aOR = 1.32, 95% CI: 1.04-1.68). Influenza vaccine effectiveness in preventing hospitalization was 21% (95% CI: -2 to 39) in current/ex-smokers and 39% in non-smokers (95% CI: 22-52). Conclusions: A history of smoking may increase the risk of hospitalization in smokers and ex-smokers. Preventing smoking could reduce hospitalizations due to influenza. Smokers and ex-smokers should be informed of the risk of hospitalization due to influenza infection, and encouraged to stop smoking. Smokers should be considered an at-risk group to be aggressively targeted for routine influenza vaccination.

The effectiveness of influenza vaccination in preventing hospitalisations of elderly individuals in two influenza seasons: a multicentre case-control study, Spain, 2013/14 and 2014/15.

Influenza vaccination may limit the impact of influenza in the community. The aim of this study was to assess the effectiveness of influenza vaccination in preventing hospitalisation in individuals aged ≥ 65 years in Spain. A multicentre case-control study was conducted in 20 Spanish hospitals during 2013/14 and 2014/15. Patients aged ≥ 65 years who were hospitalised with laboratory-confirmed influenza were matched with controls according to sex, age and date of hospitalisation. Adjusted vaccine effectiveness (VE) was calculated by multivariate conditional logistic regression. A total of 728 cases and 1,826 matched controls were included in the study. Overall VE was 36% (95% confidence interval (CI): 22-47). VE was 51% (95% CI: 15-71) in patients without high-risk medical conditions and 30% (95% CI: 14-44) in patients with them. VE was 39% (95% CI: 20-53) in patients aged 65-79 years and 34% (95% CI: 11-51) in patients aged ≥ 80 years, and was greater against the influenza A(H1N1)pdm09 subtype than the A(H3N2) subtype. Influenza vaccination was effective in preventing hospitalisations of elderly individuals.

Effect of Occupational Exposure on A(H1N1)pdm09 Infection and Hospitalization.

OBJECTIVE: To analyze relationships between occupational exposure and influenza infection and hospitalization during the 2009-2010 pandemic wave and the 2010-2011 influenza seasonal epidemic in Spain. METHODS: Occupations were classified as high, medium, or low risk of influenza exposure. To assess the risk of infection, 588 outpatient cases of influenza confirmed by reverse-transcription polymerase-chain-reaction (RT-PCR) were compared with 588 outpatients without influenza symptoms. To assess the risk of hospitalization, 337 outpatient influenza cases were compared with 337 inpatient influenza cases. RESULTS: The high risk of occupational exposure group was composed only of health care workers. After adjustment for age, sex, vaccination status, and predictive variables of influenza infection, patients with a high risk of occupational exposure had an aOR of 2.14 (95%CI: 1.25-3.66) of being an outpatient influenza case and an aOR of 0.43 (95%CI: 0.20-0.95) of being an inpatient influenza case, compared with those with a low risk. CONCLUSIONS: A high risk of occupational exposure is a risk factor for influenza infection but not for hospitalization.

Comparison of body mass index (BMI) with the CUN-BAE body adiposity estimator in the prediction of hypertension and type 2 diabetes.

BACKGROUND: Obesity is a world-wide epidemic whose prevalence is underestimated by BMI measurements, but CUN-BAE (Clínica Universidad de Navarra - Body Adiposity Estimator) estimates the percentage of body fat (BF) while incorporating information on sex and age, thus giving a better match. Our aim is to compare the BMI and CUN-BAE in determining the population attributable fraction (AFp) for obesity as a cause of chronic diseases. METHODS: We calculated the Pearson correlation coefficient between BMI and CUN-BAE, the Kappa index and the internal validity of the BMI. The risks of arterial hypertension (AHT) and diabetes mellitus (DM) and the AFp for obesity were assessed using both the BMI and CUN-BAE. RESULTS: 3888 white subjects were investigated. The overall correlation between BMI and CUN-BAE was R(2) = 0.48, which improved when sex and age were taken into account (R(2) > 0.90). The Kappa coefficient for diagnosis of obesity was low (28.7 %). The AFp was 50 % higher for DM and double for AHT when CUN-BAE was used. CONCLUSIONS: The overall correlation between BMI and CUN-BAE was not good. The AFp of obesity for AHT and DM may be underestimated if assessed using the BMI, as may the prevalence of obesity when estimated from the percentage of BF.

Smoking may increase the risk of hospitalization due to influenza.

BACKGROUND: Smoking may facilitate influenza virus infections and their severity. The objective was to investigate the risk of hospitalization due to influenza in Spanish smokers and ex-smokers. METHODS: We carried out a multicentre, case-control study in 2011. Cases [patients ≥ 18 years hospitalized > 24 h with real time polymerase chain reaction (RT-PCR)-confirmed influenza] were selected from 29 Spanish hospitals. For each case, we selected an outpatient aged ≥ 18 years with RT-PCR-confirmed influenza matched by age (±5 years), date of hospitalization of the case (±10 days) and province of residence. We collected epidemiological variables, comorbidities and the smoking history. The risk of hospitalization due to smoking was determined by the adjusted odds ratio (aOR) using logistic regression. RESULTS: We studied 471 hospitalized cases and 476 outpatient cases. Hospitalized cases had a higher frequency of influenza risk factors compared with outpatient cases. Hospitalized cases had a higher frequency of smoking (30.9% vs. 17.1%) and being ex-smokers (29.3% vs. 25.3%). Current smoking (aOR = 2.18, 95% CI: 1.23-3.87) and being an ex-smoker (aOR = 1.73, 95% CI: 1.07-2.82) were associated with the risk of hospitalization. CONCLUSIONS: Smoking may increase the risk of hospitalization in smokers and ex-smokers when infected by the influenza virus. Smoking prevention could reduce hospitalizations. Influenza vaccination is recommended for smokers.

[Primary health care professionals attitudes towards influenza immunzation in Catalonia]. / Estudio actitudes sobre vacunación antigripal en profesionales sanitarios de atención primaria de Cataluña.

OBJECTIVE: Health personnel are at risk of acquiring influenza infection and of nosocomial influenza transmission. The objective of this study was to assess the relationship between the knowledge and attitudes of primary care health personnel in Catalonia as regards influenza vaccine and the factors related to the uptake of this vaccine. DESIGN: A cross-sectional study using a web survey. SETTING: Primary care health personnel of the Catalan Health Institute. PARTICIPANTS: A total of 1212 primary health care personnel were included in the survey. Those who had medical reasons for being or not being vaccinated were excluded. RESULTS: A total of 423 replies were valid, with a 46.6% overall vaccination coverage. Vaccination rate was higher among 45 to 54 year-olds, paediatricians, those vaccinated in preceding seasons, and those living with chronic patients. There was an association between having received the vaccine and considering vaccination the best preventive action, advocating vaccination to at risk population, concern about acquiring influenza, and considering health personnel vaccination important. CONCLUSIONS: Actions taken to increase vaccination rate among health personnel should aim at correcting lack of knowledge and misconceptions about influenza vaccination of health personnel.

Prognostic value of non-specific ST-T changes and left ventricular hypertrophy electrocardiographic criteria in hypertensive patients: 16-year follow-up results from the MINACOR cohort.

BACKGROUND: Non-specific electrocardiographic ST-T wave changes and voltage criteria for left ventricular hypertrophy (LVH) have been associated with cardiovascular morbidity and mortality. The aim of the cohort study was to evaluate the prognostic value of non-specific ST-T changes and LVH electrocardiographic criteria on cardiovascular events and mortality in hypertensive patients. METHODS: A cohort study of 352 non-diabetic hypertensive patients, without associated cardiovascular disease, randomly selected from 1,780 hypertensive patients attended in a primary care center. An electrocardiogram was performed at the baseline visit (classified according to the Minnesota Code). Cardiovascular events and death from any cause during the follow-up period were evaluated. A multivariate analysis adjusted for gender, age and cardiovascular risk factors was performed. RESULTS: Data of 273 patients were analyzed: 58.2% women, age 44.1 (7.9) years, 27.8% smokers, blood pressure at baseline 142.7 (15.3)/89.3 (9.6) mmHg. During the 197.5 (59.24) month follow-up, 62 patients (22.7%) had a cardiovascular event. On multivariate analysis, age, systolic blood pressure, incidence of diabetes, smoking and electrocardiographic LVH criteria (HR 2.66 [CI 95% 1.39 - 5.10]), were significantly associated with cardiovascular events, but the presence of non-specific ST-T abnormalities (HR 0.97 [CI 95% 0.49 -1.90]) was not significantly associated with cardiovascular morbidity and mortality. CONCLUSIONS: Hypertensive patients with LVH electrocardiographic criteria have significantly higher cardiovascular mortality and morbidity, but non-specific electrocardiographic ST-T changes are not associated with cardiovascular morbidity and mortality.

Effectiveness of non-pharmaceutical measures in preventing pediatric influenza: a case-control study.

BACKGROUND: Hygiene behavior plays a relevant role in infectious disease transmission. The aim of this study was to evaluate non-pharmaceutical interventions (NPI) in preventing pediatric influenza infections. METHODS: Laboratory confirmed influenza cases occurred during 2009-10 and 2010-11 seasons matched by age and date of consultation. NPI (frequency of hand washing, alcohol-based hand sanitizer use and hand washing after touching contaminated surfaces) during seven days prior to onset of symptoms were obtained from parents of cases and controls. RESULTS: Cases presented higher prevalence of underlying conditions such as pneumonia [OR = 3.23; 95% CI: 1.38-7.58 p = 0.007], asthma [OR = 2.45; 95% CI: 1.17-5.14 p = 0.02] and having more than 1 risk factor [OR = 1.67; 95% CI: 0.99-2.82 p = 0.05]. Hand washing more than 5 times per day [aOR = 0.62; 95% CI: 0.39-0.99 p = 0.04] was the only statistically significant protective factor. When considering two age groups (pre-school age 0-4 yrs and school age 5-17) yrs , only the school age group showed a negative association for influenza infection for both washing more than 5 times per day [aOR = 0.47; 95% CI: 0.22-0.99 p = 0.04] and hand washing after touching contaminated surfaces [aOR = 0.19; 95% CI: 0.04-0.86 p = 0.03]. CONCLUSION: Frequent hand washing should be recommended to prevent influenza infection in the community setting and in special in the school age group.

Influenza vaccination of primary healthcare physicians may be associated with vaccination in their patients: a vaccination coverage study.

BACKGROUND: To assess the contribution of physician-related factors, especially their influenza vaccine status, in the vaccination coverage of their patients. METHODS: A study of vaccination coverage was carried out in Spain in 2011-12. The dependent variable (vaccination coverage in patients aged ≥ 65 years) was obtained from regional records. Information was gathered on the vaccination of physicians through an anonymous web survey. We compared the vaccination coverage of patients with the vaccination of their physicians using the Student t test. Associations were determined using a multilevel regression model. RESULTS: The coverage in patients aged ≥ 65 years was 56.3% and was higher (57.3%) in patients whose physician had been vaccinated than in those whose physician had not (55.2%) (p = 0.008). In the multilevel regression model, vaccination of the physician was associated (p = 0.049) with vaccination of their patients after controlling for the effects of age (p = 0.046), region (p = 0.089), and opinions on the effectiveness of the vaccine (p = 0.013). CONCLUSIONS: Vaccination of physicians together with their opinions on the effectiveness of the vaccine may be a predictor of vaccination coverage in their patients. Further studies are required to confirm this.

[Vaccines against varicella-zoster virus (VZV)]. / Vacunas frente al virus de la varicela zóster.

In Western countries, two attenuated varicella vaccines derived from the OKA strain are licensed: Varilrix® GlaxoSmithKline (OKA/RIT strain) and Varivax® Merck Sharp and Dohme (OKA/Merck strain). Currently, in Spain, varicella vaccination is only included in the Ministry of Health, Social Services and Equality official vaccination calendar for administration in adolescents who have not had the disease. Given the good results obtained in Navarra and Madrid with universal administration of the vaccine in children, it would be desirable to include the vaccine in the routine immunization schedule, with the administration of two doses at 15-18 months of age in the future. The protective efficacy of the attenuated herpes zoster vaccine was evaluated in the Shingles Prevention Study, which showed that in the short term (0-4 years) the vaccine reduced the incidence of herpes zoster by 53%, post-herpetic neuralgia by 66%, and the disease burden in immunocompetent persons aged ≥60 years by 61%. Another study demonstrated protective efficacy in persons aged 50-59 years. Over time, the protective efficacy decreases, but remains at acceptable levels, especially for post-herpetic neuralgia and the disease burden. Recently, the results of a controlled clinical trial (phase III) conducted in 18 countries to assess the protective efficacy of the inactivated subunit vaccine (glycoprotein E) adjuvanted with the adjuvant AS01B were published. The study inferred that the vaccine significantly reduced the incidence of herpes zoster in the short term (3.2 years) in people aged ≥50 years. Vaccine protection did not decrease with age at vaccination, ranging between 96.8% and 97.9% in all age groups.

Geographical differences in whooping cough in Catalonia, Spain, from 1990 to 2010.

BACKGROUND: Whooping cough is a communicable disease whose incidence has increased in recent years in some countries with vaccination. Since 1981, in Catalonia (Spain), cases must be reported to the Public Health Department. In 1997, surveillance changed from aggregated counts to individual report and the surveillance system was improved after 2002. Catalan public health is universal with equal coverage geographically. The aim of this study was to determine whether there are differences in whooping cough incidence in rural and urban counties. METHODS: Cases in 1990-2010 were classified as rural or urban. Incidences and risk ratios (RR) between urban and rural counties and 95% CI were calculated. Associations between rural and urban counties and structural changes during the study period were analysed. RESULTS: Twelve years of the whole study period showed differences in incidence between rural and urban counties. The incidence was higher in urban counties in seven years and rural counties in five years. There was a positive association of whooping cough incidence in rural and urban counties in four-week periods. Structural changes were detected in the following four-week periods: 4th in 1993, 7th in 1996 and 3rd 2005 in rural counties and 5th 1993, 9th in 1996 and 8th in 2007 in urban counties. CONCLUSIONS: Differences in whooping cough between rural and urban counties were found. In most years, the incidence was higher in urban than in rural counties. Rural and urban counties show similar cyclic behaviour when four-week periods were considered.

Pandemic influenza A (H1N1) in non-vaccinated, pregnant women in Spain (2009-2010).

The aim of this study was to investigate the main characteristics of non-vaccinated pregnant women who were hospitalised for influenza A (H1N1) pdm09 pandemic versus pregnant women hospitalised for non-influenza-related reasons in Spain, and to characterise the clinical presentation of the disease in this population to facilitate early diagnosis and future action programmes. Understanding influenza infection during pregnancy is important as pregnant women are a high-risk population for increased morbidity from influenza infection. We investigated the socio-demographic and clinical features of 51 non-vaccinated, pregnant women infected with the pandemic influenza A (H1N1) virus in Spain (cases) and compared them to 114 controls (non-vaccinated and non-infected pregnant women) aged 15-44 years. Substantial and significant odd ratios (ORs) for pandemic influenza A (H1N1) were found for the pregnant women who were obese compared with controls (body mass index > 30) (OR 3.03; 95% confidence intervals 1.13-8.11). The more prevalent symptoms observed in pandemic influenza-infected pregnant women were high temperature, cough (82.4%), malaise (80.5%), myalgia (56.1%), and headaches (54.9%). Our results suggest that the initial symptoms and risk factors for infection of pregnant women with the influenza A (H1N1) pdm09 virus are similar to the symptoms and risk factors for seasonal influenza, which make early diagnosis difficult, and reinforces the need to identify and protect high-risk groups.

Predictive factors of severe multilobar pneumonia and shock in patients with influenza.

PURPOSE: To identify risk factors present at admission in adult patients hospitalised due to influenza virus infection during the 2009/10 and 2010/11 seasons--including whether infection was from pandemic or seasonal influenza A infections--that were associated with the likelihood of developing severe pneumonia with multilobar involvement and shock. METHODS: Prospective cohort study. Patients hospitalised due to influenza virus infection were recruited. We collected information on sociodemographic characteristics, pre-existing medical conditions, vaccinations, toxic habits, previous medications, exposure to social environments, and EuroQoL-5D (EQ-5D). Severe pneumonia with multilobar involvement and/or shock (SPAS) was the primary outcome of interest. We constructed two multivariate logistic regression models to explain the likelihood of developing SPAS and to create a clinical prediction rule for developing SPAS that includes clinically relevant variables. RESULTS: Laboratory-confirmed A(H1N1)pdm09, EQ-5D utility score 7 days before admission, more than one comorbidity, altered mental status, dyspnoea on arrival, days from onset of symptoms, and influenza season were associated with SPAS. In addition, not being vaccinated against seasonal influenza in the previous year, anaemia, altered mental status, fever and dyspnoea on arrival at hospital, difficulties in performing activities of daily living in the previous 7 days, and days from onset of symptoms to arrival at hospital were related to the likelihood of SPAS (area under the curve value of 0.75; Hosmer-Lemeshow p value of 0.84). CONCLUSIONS: These variables should be taken into account by physicians evaluating a patient affected by influenza as additional information to that provided by the usual risk scores.

Effectiveness of Influenza Vaccination and Early Antiviral Treatment in Reducing Pneumonia Risk in Severe Influenza Cases.

INTRODUCTION: Influenza vaccination may be effective in preventing influenza infection and may reduce the risk of influenza-associated pneumonia. The study aim was to evaluate the effect of influenza vaccination in preventing pneumonia when it failed to prevent influenza hospitalization. METHODS: This was a case-control study comparing hospitalized cases of influenza with and without pneumonia in patients aged ≥18 years in 16 hospitals in Catalonia over 10 influenza seasons (2010-11 to 2019-20). Data on sociodemographic, virological characteristics, comorbidities, vaccination history, and antiviral treatment were collected and analysed. The crude odds ratio (OR) and adjusted OR (aOR) with the corresponding 95% confidence interval (CI) values were calculated. RESULTS: In total, 5080 patients hospitalized for severe influenza were included, 63.5% (3224/5080) of whom had pneumonia-mostly men (56.8%; 1830/3224) and mostly in the ≥75 age group (39.3%; 1267/3224)-and of whom 14.0% died (451/3224). Virus A and virus B accounted for 78.1% (2518/3224) and 21.9% (705/3224) of influenza types, respectively. Starting antiviral treatment ≤48 h after symptom onset (aOR = 0.69; 95%CI: 0.53-0.90) and a history of seasonal influenza vaccination (aOR = 0.85; 95%CI: 0.72-0.98) were protective factors in developing pneumonia. CONCLUSIONS: Adherence to seasonal influenza vaccination and starting antiviral treatment within 48 h of symptom onset can reduce pneumonia risk in severe influenza cases.

Impact of the Universal Implementation of Adolescent Hepatitis B Vaccination in Spain.

The aim of this study was to analyse the impact of the introduction of universal adolescent HBV vaccination on the incidence of acute hepatitis B virus (HBV) infections. Acute HBV cases reported to the Spanish National Epidemiological Surveillance Network between 2005 and 2021 were included. For regions starting adolescent vaccination in 1991-1993 and in 1994-1996, HBV incidence rates were compared by calculating the incidence rate ratio (IRR) and 95% confidence interval (CI). We also analysed the 2017 Spanish national seroprevalence survey data. The overall acute HBV incidence per 100,000 persons was 1.54 in 2005 and 0.64 in 2021 (p < 0.001). The incidence in 2014-2021 was lower for regions that started adolescent vaccination in 1991-1993 rather than in 1994-1996 (IRR 0.76; 95% CI 0.72-0.83; p < 0.001). In the 20-29 age group, incidence in regions that started adolescent vaccination in 1991-1993 was also lower (IRR 0.87; 95% CI 0.77-0.98; p = 0.02 in 2005-2013 and IRR 0.71; 95% CI 0.56-0·90; p < 0.001 in 2014-2021). Anti-HBc prevalence in the 35-39 age group was lower in the regions that started vaccination earlier, although the difference was not statistically significant (p = 0.09). Acute HBV incidence decreased more in the young adult population in regions that began adolescent vaccination earlier. Maintaining high universal vaccination coverage in the first year of life and in at-risk groups is necessary to achieve HBV elimination by 2030.