COVID-19 vaccination coverage in patients with chronic obstructive pulmonary disease – A cross-sectional study in Hungary

IntroductionCoronavirus infection is a particular risk for patients with chronic obstructive pulmonary disease (COPD), because they are much more likely to become severely ill due to oxygen supply problems. Primary prevention, including COVID-19 vaccination is of paramount importance in this disease group. The aim of our study was to assess COVID-19 vaccination coverage in COPD patients during the first vaccination campaign of the COVID-19 pandemic.MethodsA cross-sectional observational study (CHANCE) has been conducted in COPD patients in the eastern, western and central regions of Hungary from 15th November 2021. The anthropometric, respiratory function test results and vaccination status of 1,511 randomly selected patients were recorded who were aged 35 years and older.ResultsThe median age was 67 (61–72) years, for men: 67 (62–73) and for women: 66 (60–72) years, with 47.98 % men and 52.02 % women in our sample. The prevalence of vaccination coverage for the first COVID-19 vaccine dose was 88.62 %, whereas 86.57 % of the patients received the second vaccine dose. When unvaccinated (n = 172) and double vaccinated (n = 1308) patients were compared, the difference was significant both in quality of life (CAT: 17 (12–23) vs 14 (10–19); p < 0.001) and severity of dyspnea (mMRC: 2 (2–2) vs 2 (1–2); p = 0.048). The COVID-19 infection rate between double vaccinated and unvaccinated patients was 1.61 % vs 22.67 %; p < 0.001 six months after vaccination. The difference between unvaccinated and vaccinated patients was significant (8.14 % vs 0.08 %; p < 0.001) among those with acute COVID-19 infection hospitalized. In terms of post-COVID symptoms, single or double vaccinated patients had significantly fewer outpatient hospital admissions than unvaccinated patients (7.56 vs 0 %; p < 0.001).ConclusionThe COVID-19 vaccination coverage was satisfactory in our sample. The uptake of COVID-19 vaccines by patients with COPD is of utmost importance because they are much more likely to develop severe complications.     

COVID-19 vaccine confidence and reasons for vaccination among health care workers and household members

BackgroundThe majority of healthcare workers (HCW) in the US report being fully vaccinated against COVID-19, yet little is known about vaccine decision-making for their household members, including children.MethodsCross-sectional survey July–August 2021 of HCW and their household members in Minnesota.Results94 % of eligible participants were vaccinated with the most common reasons being wanting to protect oneself, family and loved ones. Safety concerns were the most commonly reported reasons for not being vaccinated; a significantly higher proportion of unvaccinated compared to vaccinated HCW (58 % vs 12 %, p = 0.0035) and household adults (25 % vs 5 %, p = 0.03) reported prior SARS-CoV-2 infection. Nearly half of unvaccinated adults and two-thirds of unvaccinated children would be vaccinated if a vaccine mandate were in place.ConclusionsDespite high COVID-19 vaccine acceptance among HCWs, more research is required to identify and address the needs and concerns of healthcare workers who decline COVID-19 vaccination despite availability.     

Does BCG provide long-term protection against SARS-CoV-2 infection? A case–control study in Quebec,Canada

BackgroundEarly in the coronavirus disease 2019 (COVID-19) pandemic, before severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines became available, it was hypothesized that BCG (Bacillus Calmette–Guérin), which stimulates innate immunity, could provide protection against SARS-CoV-2. Numerous ecological studies, plagued by methodological deficiencies, revealed a country-level association between BCG use and lower COVID-19 incidence and mortality. We aimed to determine whether BCG administered in early life decreased the risk of SARS-CoV-2 infection in adulthood and the severity of COVID-19.MethodsThis case-control study was conducted in Quebec, Canada. Cases were patients with a positive SARS-CoV-2 nucleic acid amplification test performed at two hospitals between March–October 2020. Controls were identified among patients with non-COVID-19 samples processed by the same microbiology laboratories during the same period. Enrolment was limited to individuals born in Quebec between 1956 and 1976, whose vaccine status was accessible in a computerized registry of 4.2 million BCG vaccinations.ResultsWe recruited 920 cases and 2123 controls. Fifty-four percent of cases (n = 424) and 53% of controls (n = 1127) had received BCG during childhood (OR: 1.03; 95% CI: 0.89–1.21), while 12% of cases (n = 114) and 11% of controls (n = 235) had received two or more BCG doses (OR: 1.14; 95% CI: 0.88–1.46). After adjusting for age, sex, material deprivation, recruiting hospital and occupation there was no evidence of protection conferred by BCG against SARS-CoV-2 (AOR: 1.01; 95% CI: 0.84–1.21). Among cases, 77 (8.4%) needed hospitalization and 18 (2.0%) died. The vaccinated were as likely as the unvaccinated to require hospitalization (AOR: 1.01, 95% CI: 0.62–1.67) or to die (AOR: 0.85, 95% CI: 0.32–2.39).ConclusionsBCG does not provide long-term protection against symptomatic COVID-19 or severe forms of the disease.     

Tolerance of BNT162b2 mRNA COVI-19 vaccine in patients with a medical history of COVID-19 disease: A case control study

IntroductionStudies evaluating BNT162b2 mRNA Covid-19 vaccine safety excluded subjects with a previous history of COVID-19 infection. The aim of our study was to focus on the tolerance of this vaccine this population.MethodsAn anonymous self-reporting survey related to safety and tolerance of vaccine was completed by subjects 21 to 28 days after the first vaccine dose in two vaccination centers.ResultsSubjects with prior COVID-19 disease history (n = 61) had higher systemic reactions than subjects without any previous history (n = 1987) (45.9% vs 29.7%, p = 0.01). Asthenia, headache and fever were significantly more frequent in COVID-19 + group than negative group (25.6% vs 15.2% p = 0.045, 19.7% vs 9.3% p = 0.01, 6.5% vs 0.9% p = 0.003 respectively). Grade of severity was higher in COVID-19 + than in COVID-19 - group (p = 0.03).ConclusionOur study confirms a higher risk of side effects in patients with preexisting SARS-CoV-2 disease but with a good overall tolerance.     

Impact of prior vaccination with CovishieldTM and Covaxin® on mortality among symptomatic COVID-19 patients during the second wave of the pandemic in South India during April and May 2021: a cohort study

BackgroundCOVID-19 vaccines were authorised for emergency use to mitigate the impact of the pandemic. This study evaluated the effect of prior vaccination with either Oxford Astra Zeneca’s Covishield? or Bharath Biotech’s Covaxin® on mortality among symptomatic COVID-19 patients during the second wave of the pandemic in India.MethodologyIn this cohort study comprising of RT-PCR confirmed symptomatic COVID-19 patients presenting during April and May 2021, the effect of prior vaccination on mortality (primary outcome), need for hospitalization, oxygen therapy, non-invasive ventilation (NIV) and intensive care unit (ICU) admission were assessed and expressed as risk ratio (RR) with 95% confidence intervals (CI).ResultsThe mean (SD) age of the cohort (n = 4183) was 46.3 (15.5) years; 17.9% (748/4183) had received at least one dose of Covishield? and 4.8% (201/4183) had received Covaxin®. Mortality was 0.2% (95% CI: 0.2% – 0.7%), 3.5% (1.9–5.2%), 6.2% (0.3–12%) and 12.9% (11.8–14.1%) among fully vaccinated (>2 weeks after two doses), partially vaccinated (>2 weeks after one dose or <2 weeks after two doses), indeterminate (<2 weeks after one dose) and unvaccinated patients respectively. The difference in mortality among unvaccinated vs. fully vaccinated was 12.7% (95% CI: 11.4–13.9%), unvaccinated vs. partially vaccinated was 9.4% (7.4–11.4%) and unvaccinated vs. indeterminate vaccinated was 6.8% (0.8–12.7%). On adjusted analysis, as compared to unvaccinated patients, at least one dose of vaccine reduced the need for hospitalization (RR: 0.40; 95% CI: 0.35–0.47), oxygen (0.33; 0.27–0.40), NIV (0.23; 0.17–0.32), ICU admission (0.18; 0.12–0.27) and mortality (0.18; 0.11–0.29).ConclusionAmong symptomatic COVID-19 patients, prior vaccination with Covishield ? or Covaxin® impacted the severity of illness and reduced mortality during a period of widespread delta variant circulation. Full vaccination conferred greater protection than partial vaccination.     

Survey of influenza vaccine knowledge,attitudes, and beliefs among pregnant women in the 2016–17 season

ObjectivesInfluenza vaccination coverage among pregnant women in the United States is suboptimal. We surveyed women who were pregnant during the 2016–17 influenza season to assess knowledge and attitudes regarding influenza vaccination.MethodsWe identified and sampled pregnant women to include approximately equal numbers of vaccinated and unvaccinated women from strata defined by vaccination status and trimester from four integrated health systems in the Vaccine Safety Datalink (VSD). Potential participants were contacted via mail and telephone to complete a standardized survey. Characteristics and responses of women vaccinated and unvaccinated during pregnancy were compared.ResultsThe survey was completed by 510 (48%) of 1062 contacted women; 500 were included in the analysis. Vaccine receipt while pregnant was associated with primigravida status (p = 0.02), college degree (p = 0.01), employment in health care (p < 0.01), and history of routine annual influenza vaccination (p < 0.01). Among 330 vaccinated women, the primary reasons for vaccination included protection of self and baby from influenza (n = 233, 71%), and medical professional recommendation (n = 46, 14%). Multiple reasons were given for nonvaccination, but concern about ‘negative effects’ was cited most often (n = 44, 29%). Vaccinated women were significantly more likely to believe that influenza vaccines are safe and effective, and to recognize the potential for harm from influenza infection. Nearly all women reported receiving at least one influenza vaccination recommendation from a healthcare provider.ConclusionsVaccinated pregnant women were more likely to receive routine annual influenza vaccine compared to those not vaccinated. Recommendations by obstetric providers should be supplemented with efforts to encourage women of childbearing age to receive annual vaccination.     

CNS demyelinating disease following inactivated or viral vector SARS-CoV-2 vaccines: A case series

BackgroundSeveral reports have been documented in possible association with the administration of different severe acute respiratory coronavirus 2 (SARS-CoV-2) vaccines and central nervous system (CNS)demyelinating disorders, specifically post mRNA vaccines. We report twelve cases of developing Multiple sclerosis (MS) or Neuromyelitis Optica spectrum disorders (NMOSD) following neither the first nor second dose of inactivated or viral vector COVID-19 vaccine.MethodsWe retrospectively compiled twelve patients' medical information with a new onset of MS or NMOSD in their first six weeks following a COVID-19 vaccine.ResultsWe report twelve cases of MS (n = 9), clinically isolated syndrome (CIS)(n = 1), and NMOSD (n = 2) following COVID-19 inactivated vaccines (n = 11) or viral vector vaccines (n = 1), within some days following either the first (n = 3), second dose (n = 8), or third dose (n = 1). Their median age was 33.3 years, ranging from 19 to 53 years. Ten were women (83 %). All patients fully (n = 5) or partially (n = 2) recovered after receiving 3 doses of Corticosteroids. Common medications were Natalizumab, Teriflunomide, Dimethyl fumarate, and Rituximab. Also, Interferon beta 1-a was administered to one patient with severe symptoms of numbness.ConclusionOur case series identifies the Sinopharm BBIBP-CorV and the AstraZeneca AZD1222 vaccines as potential triggers for CNS demyelinating diseases. Vaccine administration routines are not affected by these rare and coincidental events. However, these manifestations are not deniable and require serious attention. Further investigations are needed to clarify the actual mechanisms and real associations.     

Factors associated with COVID-19 vaccination during June–October 2021: A multi-site prospective study

IntroductionVaccine hesitancy presents a challenge to COVID-19 control efforts. To identify beliefs associated with delayed vaccine uptake, we developed and implemented a vaccine hesitancy survey for the COVID-19 Community Research Partnership.MethodsIn June 2021, we assessed attitudes and beliefs associated with COVID-19 vaccination using an online survey. Self-reported vaccination data were requested daily through October 2021. We compared responses between vaccinated and unvaccinated respondents using absolute standardized mean differences (ASMD). We assessed validity and reliability using exploratory factor analysis and identified latent factors associated with a subset of survey items. Cox proportional hazards models and mediation analyses assessed predictors of subsequent vaccination among those initially unvaccinated.ResultsIn June 2021, 29,522 vaccinated and 1,272 unvaccinated participants completed surveys. Among those unvaccinated in June 2021, 559 (43.9 %) became vaccinated by October 31, 2021. In June, unvaccinated participants were less likely to feel “very concerned” about getting COVID-19 than vaccinated participants (10.6 % vs. 43.3 %, ASMD 0.792). Among those initially unvaccinated, greater intent to become vaccinated was associated with getting vaccinated and shorter time to vaccination. However, even among participants who reported no intention to become vaccinated, 28.5 % reported vaccination before study end. Two latent factors predicted subsequent vaccination—being ‘more receptive’ was derived from motivation to protect one’s own or others’ health and resume usual activities; being ‘less receptive’ was derived from concerns about COVID-19 vaccines. In a Cox model, both factors were partially mediated by vaccination intention.ConclusionThis study characterizes vaccine hesitant individuals and identifies predictors of eventual COVID-19 vaccination through October 31, 2021. Even individuals with no intention to be vaccinated can shift to vaccine uptake. Our data suggest factors of perceived severity of COVID-19 disease, vaccine safety, and trust in the vaccine development process are predictive of vaccination and may be important opportunities for ongoing interventions.     

Immunocompromise among vaccinated versus unvaccinated COVID-19 cases admitted to critical care in Ireland,July to October 2021

As the COVID-19 pandemic progressed, so too did the proportion of cases admitted to critical care in Ireland who were fully vaccinated. Reporting of this observation has public health implications as incorrect interpretation may affect public confidence in COVID-19 vaccines. A potential explanation is the reduced ability of those who are immunocompromised to produce an adequate, sustained immune response to vaccination. We conducted an analysis of the association between COVID-19 vaccination status and underlying degree of immunocompromise among a cohort of critical care patients all with a confirmed diagnosis of COVID-19 admitted to critical care between July and October 2021. Multinomial logistic regression was used to estimate an odds ratio of immunocompromise among vaccinated COVID-19 cases in critical care compared to unvaccinated cases. In this study, we found a statistically significant association between the vaccination status of severe COVID-19 cases requiring critical care admission and underlying immunocompromise. Fully vaccinated patients were significantly more likely to be highly (OR = 19.3, 95 % CI 7.7–48.1) or moderately immunocompromised (OR = 9.6, 95 % CI 5.0–18.1) compared to unvaccinated patients with COVID-19. These findings support our hypothesis, that highly immunocompromised patients are less likely to produce an adequate and sustained immune response to COVID-19 vaccination, and are therefore more likely to require critical care admission for COVID-19 infection.     

A national survey of COVID-19 vaccine acceptance in Nigeria

IntroductionThe COVID-19 vaccine is essential to reduce the global impact of the pandemic. Understanding its acceptance is key to Nigeria’s national COVID-19 control strategies.MethodsBetween the 6th and 22nd of January 2021, we conducted a non-probability convenience sampling of 3076 respondents using online and in-person interviews to assess the prevalence and predictors of the COVID-19 vaccine acceptance in Nigeria.FindingsOf the 3076 recruited participants, 74.7% (n = 2300/3076) had tertiary education. The median age group was 30–39 years (35.1%, n = 1097/3076) whereas 31% (n = 952/3076) of all respondents had a monthly income<30,000 Naira (65 USD). The survey results indicated that a wide range of the respondents were in government employment (34.1%, n = 1050/3076). The majority of our study participants (92.2%, n = 2835/3076) believe that COVID-19 is real and not a hoax. Only 27.9% (n = 858/3076) of the study participants have been tested for COVID-19 and 17.8 % (n = 152/858) of the tested respondents were COVID-19 positive by PCR. Half (50.7%; n = 1560/3076) of the study participants were willing to take the vaccine once available. The majority of the respondents (81.1%, n = 2496/3076) were not willing to pay for the vaccine. Only 15.9% (n = 483/3076) of the respondents rated the government’s handling of the pandemic above average. The potential acceptance of the COVID-19 vaccine was significantly affected by the age and the monthly income of the respondents. Respondents older than 60 years old (OR: 3.02, 95% CI: 1.69,5.41; p < 0.001) and those that earn between 250,000–500,000 Naira monthly (OR: 1.38; 95% CI: 1.11,1.70; p < 0.001) were more likely to accept the COVID-19 vaccine respectively. In addition, the respondents’ perception of the existence of the disease (OR: 1.45; 95% CI: 0.99,2.18; p > 0.05), the need for a COVID-19 vaccine (OR: 16; 95% CI: 11.63,22.10; p < 0.001), the willingness to pay (OR: 1.68; 95% CI: 1.39,2.01; p < 0.001) and the rating of the government handling of the pandemic (OR: 2.25; 95% CI: 1.57,3.23; p < 0.001) were critical to the acceptance of the COVID-19 vaccine.InterpretationWith 50.7% vaccine acceptance, Nigeria’s public health policymakers must prioritize and develop strategies that will effectively increase COVID-19 vaccine acceptance across the country with emphasis on trust, transparency and strong leadership.     

Inactive SARS-CoV-2 vaccine generates high antibody responses in healthcare workers with and without prior infection

Background and ObjectivesHealthcare workers (HCWs) were among the first groups to be vaccinated in Turkey. The data to be obtained by the vaccination of HCWs would guide wide spread vaccination programs.Materials and MethodsThe study included 330 HCWs working at Istanbul University-Cerrahpa?a, Cerrahpa?a Medical Faculty Hospital and vaccinated with inactive CoronaVac (Sinovac Life Sciences, China) SARS-CoV-2 vaccine in two doses (28 days apart). Anti-Spike /RBD IgG levels were measured 14 days after the first dose and 28 days after the second dose. Chemiluminescent microparticle immunoassay (CMIA) (ARCHITECT IgG II Quant test, Abbott, USA), which is 100% compatible with plaque reduction neutralization test (PRNT), was used.ResultsOf the participants, 211 (63.9%) were female, 119 (36.1%) were male, and mean age was 39.6 ± 7.7 years. In those without prior COVID-19 history; (n = 255) antibody positivity was detected as 48.2% (95% CI: 42.1–54.3) 14 days after the first dose of vaccine, and 99.2% (95% CI: 98.1–100) at day 28 after the second dose. Antibody titers were significantly lower in patients with hypertension (p = 0.011). In those with prior history of COVID-19 (n = 75); both the antibody positivity rates after the first vaccine (48.2% vs 100%, p = 0.000) and the anti-spike/RBD antibody levels after the second vaccine (with a ≥ 1050 AU/mL titer equivalent to PRNT 1/80 dilution) was significant than infection-naive group (25.9% vs. 54.7%, p = 0.000). Antibody positivity after two doses of vaccination for all study group was 99.4% (95% CI: 98.6–100).ConclusionsTwo doses CoronaVac produce effective humoral immunity in HCWs. Antibody response is significantly higher in those with prior history of COVID-19 than infection-naive group. Given no significant benefit of the second dose, a single shot of vaccination may be sufficient for those with prior history of COVID-19. Monitoring humoral and cellular immune responses, considering new variants, is required to validate this approach.     

Poor immune response to coronavirus disease vaccines in decompensated cirrhosis patients and liver transplant recipients

Background and aimsRecent studies have reported poor humoral immune response to mRNA vaccines in patients with chronic liver disease (CLD). However, the immunogenicity of ChAdOx1 (vector-based) and BBV152 (inactivated virus) vaccines in patients with CLD and liver transplant recipients (LTRs) is unknown. Therefore, we aimed to assess the immunogenicity of ChAdOx1 and BBV152 vaccines in patients with CLD (including cirrhosis patients) and LTRs.MethodsIn this single-center prospective study, consecutive completely vaccinated (ChAdOx1 or BBV152) non-cirrhosis CLD patients, those with cirrhosis, and LTRs were compared with matched healthy controls for anti-spike antibody and cellular response.ResultsSixty healthy individuals, 50 NCCLD patients, 63 compensated and 50 decompensated cirrhosis, and 17 LTRs were included. The proportion of non-responders was similar among the healthy control (8 %), non-cirrhosis CLD (16 %), and compensated cirrhosis groups (17.5 %;p = 0.3). However, a higher proportion of patients with decompensated cirrhosis (34 %) and LTRs (59 %) were non-responders than the healthy controls (p = 0.001). Cluster of differentiation (CD) 4-effector cells were lower in patients with non-cirrhosis CLD and compensated cirrhosis. CD4-naïve, CD4-effector, B, and B-memory cells were lower in the decompensated cirrhosis group. Although the central memory cells were higher in the decompensated cirrhosis group, they could not differentiate into effector cells. CD4- and CD8-naïve cells were higher in the marrow in the LTRs, while the CD4-effector memory cells and CD4- and CD8-effector cells were lower in the LTRs. Furthermore, B cells were more deficient in the LTRs, suggesting poor antibody response.ConclusionPatients with decompensated cirrhosis and LTRs demonstrated suboptimal humoral and cellular immune responses against recombinant and inactivated COVID-19 vaccines.     

Public perception of COVID-19 vaccines through analysis of Twitter content and users

BackgroundWith the global continuation of the COVID-19 pandemic, the large-scale administration of a SARS-CoV-2 vaccine is crucial to achieve herd immunity and curtail further spread of the virus, but success is contingent on public understanding and vaccine uptake. We aim to understand public perception about vaccines for COVID-19 through the wide-scale, organic discussion on Twitter.MethodsThis cross-sectional observational study included Twitter posts matching the search criteria ((‘covid*’ OR ‘coronavirus’) AND ‘vaccine’) posted during vaccine development from February 1st through December 11th, 2020. These COVID-19 vaccine related posts were analyzed with topic modeling, sentiment and emotion analysis, and demographic inference of users to provide insight into the evolution of public attitudes throughout the study period.FindingsWe evaluated 2,287,344 English tweets from 948,666 user accounts. Individuals represented 87.9 % (n = 834,224) of user accounts. Of individuals, men (n = 560,824) outnumbered women (n = 273,400) by 2:1 and 39.5 % (n = 329,776) of individuals were ≥40 years old. Daily mean sentiment fluctuated congruent with news events, but overall trended positively. Trust, anticipation, and fear were the three most predominant emotions; while fear was the most predominant emotion early in the study period, trust outpaced fear from April 2020 onward. Fear was more prevalent in tweets by individuals (26.3 % vs. organizations 19.4 %; p < 0.001), specifically among women (28.4 % vs. males 25.4 %; p < 0.001). Multiple topics had a monthly trend towards more positive sentiment. Tweets comparing COVID-19 to the influenza vaccine had strongly negative early sentiment but improved over time.InterpretationThis study successfully explores sentiment, emotion, topics, and user demographics to elucidate important trends in public perception about COVID-19 vaccines. While public perception trended positively over the study period, some trends, especially within certain topic and demographic clusters, are concerning for COVID-19 vaccine hesitancy. These insights can provide targets for educational interventions and opportunity for continued real-time monitoring.     

A randomized controlled trial of antibody response to 2018–19 cell-based vs. egg-based quadrivalent inactivated influenza vaccine in children

BackgroundCurrent influenza vaccine effectiveness (VE) improvement efforts focus on minimizing egg adaptation mutations during manufacture. This study compared immune response of two FDA-approved quadrivalent inactivated influenza vaccines in an unblinded randomized controlled trial.MethodsParticipants were 144 community dwelling, healthy children/adolescents aged 4–20 years, randomized 1:1 in blocks of 4 to a vaccine grown in cell culture (ccIIV4 [Flucelvax®]; n = 85); or in egg medium (IIV4 [Fluzone ®]; n = 83). Blood was drawn at day 0 prevaccination and at day 28 (19–35 days) post vaccination. Hemagglutination inhibition (HI) assays against A/H1N1 and both B strains and microneutralization (MN) assays against egg-based and cell-based A/H3N2 strains were conducted. The primary outcome measure was seroconversion (day 28/day 0 titer ratio ≥ 4 with day 28 titer ≥ 40). Secondary outcomes were elevated titers (day 28 HI titer ≥ 1:110), geometric mean titers (GMTs) and mean fold rise (MFR) in titers. Outcomes were compared for 74 ccIIV4 recipients and 70 IIV4 recipients, and for those vaccinated and unvaccinated the previous year. Only the HI and MN laboratory analysis team was blinded to group assignment.ResultsIn this racially diverse (81% non-white) group of children with a median age of 14 years, baseline demographics did not differ between vaccine groups. At day 0, half or more in each vaccine group had elevated HI or MN titers. Low seroconversion rates (14%-35%) were found; they did not differ between groups. Among 2018–19 ccIIV4 recipients, those unvaccinated in the previous season showed significantly higher MFR against A/H1N1 and A/H3N2 cell-grown virus than the previously vaccinated. Similar results were found for MFR against B/Victoria among 2018–2019 IIV4 recipients.ConclusionIn mostly older children with high baseline titers, no differences in seroconversion or other measures of antibody titers were found between ccIIV4 and IIV4 recipients against egg- and cell-grown influenza vaccine viruses.Clinical Trials NoNCT03614975.     

Let's talk about COVID-19 vaccination: Relevance of conversations about COVID-19 vaccination and information sources on vaccination intention in Switzerland

BackgroundCOVID-19 vaccine hesitancy is known to be more pronounced among young people. However, there are a lack of studies examining determinants of COVID-19 vaccination intention in the general population in this young age-group in Switzerland, and in particular, studies investigating the influence of information sources and social networks on vaccination intention are missing.MethodsThe cross-sectional study “COVIDisc – Discussion with young people about the corona pandemic” provided the opportunity to investigate COVID-19 vaccination intention in 893 individuals aged 15–34 years from the cantons of Zurich, Thurgau, and Ticino in Switzerland. An online survey was administered between 10 November 2020 and 5 January 2021. Associations of public information sources and conversations about COVID-19 with COVID-19 vaccination intention were analyzed with multivariable logistic regression and mediation analysis using generalized structural equation modeling.Results51.5% of the participants intended or probably intended to get vaccinated once the vaccine would be available. Using print or online news (AOR 1.50, 95% CI 1.09–2.07) as an information source and having conversations about the COVID-19 vaccine (AOR 2.09, 95% CI 1.52–2.87) increased participants' COVID-19 vaccination intention. The effects of female gender (b = −0.267, p = 0.039) and risk perception (b = 0.163, p = 0.028) were partially mediated by having conversations about the COVID-19 vaccine. The effects of age (b = −0.036, p = 0.016), secondary educational level (b = 0.541, p = 0.010) and tertiary educational level (b = 0.726, p = 0.006) were fully mediated via having conversations about the COVID-19 vaccine.ConclusionsConversations and campaigns should start even before vaccines become available. Our data support interventions for young women and less educated people using social norms and supporting information seeking with news. Trust and risk perceptions are essential foundations for vaccine intentions.     

Short-term safety of COVID-19 mRNA vaccines with respect to all-cause mortality in the older population in Norway

BackgroundThere have been concerns about COVID-19 vaccination safety among frail older individuals. We investigated the relationship between COVID-19 mRNA vaccination and mortality among individuals aged ≥ 70 years and whether mortality varies across four groups of health services used.MethodsIn this nationwide cohort study, we included 688,152 individuals aged ≥ 70 years at the start of the Norwegian vaccination campaign (December 27, 2020). We collected individual-level data from the Norwegian Emergency Preparedness Register for COVID-19. Vaccinated and unvaccinated individuals were matched (1:1 ratio) on the date of vaccination based on sociodemographic and clinical characteristics. The main outcome was all-cause mortality during 21 days after first dose of COVID-19 mRNA vaccination. Kaplan-Meier survival functions were estimated for the vaccinated and unvaccinated groups. We used Cox proportional-hazards regression to estimate hazard ratios (HRs) of death between vaccinated and unvaccinated individuals, with associated 95% confidence intervals (CIs), overall and by use of health services (none, home-based, short- and long-term nursing homes) and age group.ResultsBetween December 27, 2020, and March 31, 2021, 420,771 older individuals (61.1%) were vaccinated against COVID-19. The Kaplan-Meier estimates based on the matched study sample showed a small absolute risk difference in all-cause mortality between vaccinated and unvaccinated individuals, with a lower mortality in the vaccinated group (overall HR 0.28 [95% CI: 0.24–0.31]). Similar results were obtained in analyses stratified by use of health services and age group.ConclusionWe found no evidence of increased short-term mortality among vaccinated individuals in the older population after matching on sociodemographic and clinical characteristics affecting vaccination and mortality.     

Effectiveness of adenovirus type 5 vectored and inactivated COVID-19 vaccines against symptomatic COVID-19, COVID-19 pneumonia,and severe COVID-19 caused by the B.1.617.2 (Delta) variant: Evidence from an outbreak in Yunnan,China, 2021

BackgroundIn partial response to the coronavirus disease 2019 (COVID-19) pandemic, countries around the world are conducting large-scale vaccination campaigns. Real-world estimates of vaccine effectiveness (VE) against the B.1.617.2 (Delta) variant are still limited. An outbreak in Ruili city of China provided an opportunity to evaluate VE against the Delta variant of two types of COVID-19 vaccines in use in China and globally – inactivated (CoronaVac and BBIBP-CorV) and adenovirus type 5 vectored (Convidecia) vaccines.MethodsWe estimated VE using a retrospective cohort study two months after the Ruili vaccination campaign (median: 63 days). Close contacts of infected people (Chinese nationality, 18 years and above) were included to assess VE against symptomatic Covid-19, COVID-19 pneumonia, and severe COVID-19. We calculated the relative risks (RR) of the outcomes for unvaccinated compared with fully vaccinated individuals. We used logistic regression analyses to estimate adjusted VEs, controlling for gender and age group (18–59 years and 60 years and over).We compared unvaccinated and fully vaccinated individuals on duration of RT-PCR positivity and Ct value.FindingsThere were 686 close contacts eligible for VE estimates. Adjusted VE of ad5-vectored vaccine was 61.5% (95% CI, 9.5–83.6) against symptomatic COVID-19, 67.9% (95%CI: 1.7–89.9) against pneumonia, and 100% (95%CI: 36.6–100) against severe/critical illness. For the two inactivated vaccines, combined VE was 74.6% (95% CI, 36.0–90.0) against symptomatic COVID-19, 76.7% (95% CI: 19.3–93.3) against pneumonia, and 100% (95% CI: 47.6–100) against severe/critical COVID-19. There were no statistically significant differences in VE between two inactivated vaccines for symptomatic COVID-19 and for pneumonia, nor were there statistically significant differences between inactivated and ad5-vectored VE in any of the three outcomes. The median durations of RT-PCR positivity were 17 days for fifteen people vaccinated with an inactivated vaccine, 18 days for forty-four people vaccinated with the Ad5 vectored vaccine, and 26 days for eleven unvaccinated individuals. InterpretationThese results provide reassuring evidence that the three vaccines are effective at preventing Delta-variant COVID-19 in short term following vaccination campaign, and are most effective at preventing more serious illness. The findings of reduced duration of RT-PCR positivity and length of hospital stay associated with full vaccination suggests potential saving of health-care system resources.