25-Hydroxyvitamin D concentrations do not affect the humoral or cellular immune response following SARS-CoV-2 mRNA vaccinations

BACKGROUND

To improve effectiveness of vaccination against SARS-CoV-2, it is important to identify factors that influence the immune response induced by vaccination. Evidence for the role of vitamin D in immune response against SARS-CoV-2 is contradictory. It is therefore of interest whether 25-hydroxyvitamin D (25[OH]D) concentrations affect the humoral and/or cellular response following SARS-CoV-2 vaccination.

METHODS

In this prospective cohort study, blood samples were collected from 98 SARS-CoV-2 naive health care workers (HCW) receiving the first two doses of either BNT162b2 or mRNA-1273 in 2021. Wild-type spike (S) protein binding and neutralizing antibodies were determined approximately three weeks after the first dose and four to five weeks after the second dose. Antigen specific T-cells and functionality (proliferative response and interferon gamma [IFN-γ] release) were determined in 18 participants four weeks after the second dose of BNT162b2. We studied the association between 25(OH)D concentrations, which were determined prior to vaccination, and humoral and cellular immune responses following vaccination.

RESULTS

We found no association between 25(OH)D concentrations (median 55.9 nmol/L [IQR 40.5-69.8]) and binding or neutralizing antibody titers after complete vaccination (fold change of antibody titers per 10 nmol/L 25(OH)D increase: 0.98 [95% CI 0.93-1.04] and 1.03 [95% CI: 0.96-1.11], respectively), adjusted for age, sex and type of mRNA vaccine. Subsequently, continuous 25(OH)D concentrations were divided into commonly used clinical categories (<25 nmol/L [n = 6, 6%], 25-49 nmol/L [n = 33, 34%], 50-75 nmol/L [n = 37, 38%] and ≥75 nmol/L [n = 22, 22%]), but no association with the humoral immune response following vaccination was found. Also, 25(OH)D concentrations were not associated with the SARS-CoV-2 specific T cell response.

CONCLUSION

No association was found between 25(OH)D concentrations and the humoral or cellular immune response following mRNA vaccination against SARS-CoV-2. Based on our findings there is no rationale to advise vitamin D optimization preceding SARS-CoV-2 vaccination in HCW with moderate vitamin D status.

The Impact of First-Time SARS-CoV-2 Infection on Human Anelloviruses

Members of the Anelloviridae family dominate the blood virome, emerging early in life. The anellome, representing the variety of anelloviruses within an individual, stabilizes by adulthood. Despite their supposedly commensal nature, elevated anellovirus concentrations under immunosuppressive treatment indicate an equilibrium controlled by immunity. Here, we investigated whether anelloviruses are sensitive to the immune activation that accompanies a secondary infection. As a model, we investigated 19 health care workers (HCWs) with initial SARS-CoV-2 infection, with blood sampling performed pre and post infection every 4 weeks in a 3-month-follow-up during the early 2020 COVID-19 pandemic. A concurrently followed control group (n = 27) remained SARS-CoV-2-negative. Serum anellovirus loads were measured using qPCR. A significant decrease in anellovirus load was found in the first weeks after SARS-CoV-2 infection, whereas anellovirus concentrations remained stable in the uninfected control group. A restored anellovirus load was seen approximately 10 weeks after SARS-CoV-2 infection. For five subjects, an in-time anellome analysis via Illumina sequencing could be performed. In three of the five HCWs, the anellome visibly changed during SARS-CoV-2 infection and returned to baseline in two of these cases. In conclusion, anellovirus loads in blood can temporarily decrease upon an acute secondary infection.

Improving emergency department flow by introducing a simple time out moment (The TRAFFIC LIGHT study)

BACKGROUND AND IMPORTANCE

Long waiting times in the emergency department (ED) is an increasing problem in the recent years and is expected to become an even bigger problem in the future Objective: We aimed to test the hypothesis whether increasing awareness of the time lapse with the treating physician, 2 hours after patient arrival, can reduce long patient turnaround time (TAT).

METHOD

In this prospective single-center cohort study we compared and analyzed patient TAT in the ED before and after implementation of a so called 'traffic light' moment 2 hours after patient arrival. At this 'traffic light' moment a team member contacted the treating physician to increased awareness over the time lapse. Difference in percentage of patients who stayed more than 4 hours in the ED before and after intervention was the primary outcome Results: Between October 2nd 2021 and January 2nd,2022 1494 patients were included for primary outcome analysis. A total of 419 patients (n=740, 56.6%) had a TAT of less than 4 hour in the ED before intervention, compared to 497 (n=754, 65.9%) after intervention (p <0.001). Median time spent in de ED before intervention was 3:40 (IQR 2:24 - 5:04) compared to 3:15 (IQR 2:03 - 4:38) after intervention (p<0.001).

CONCLUSION

This simple and low-cost intervention reduces the ED length of stay significantly. Although multiple interventions will be required to ensure less patients spending more than 4-hours in the ED, a 'traffic light' moment can be a simple and an effective tool.

[Glycemia reduction in type 2 diabetes patients with low cardiovascular risk]

In persons with type 2 diabetes without established cardiovascular complications data are lacking on the comparative effectiveness of commonly used glucose-lowering medications, when added to metformin, with respect to glycemic outcomes as well as microvascular and cardiovascular disease outcomes. The GRADE trial compared the ability of four glucose-lowering remedies to achieve and maintain a defined glycated hemoglobin target and to protect the participant from microvascular and macrovascular complications. In this article, we comment on the relevance of this trial with specific attention for the notion that GLP-1 receptor agonists seem to have a primary preventive effect.

Why not to pick your nose: Association between nose picking and SARS-CoV-2 incidence, a cohort study in hospital health care workers

BACKGROUND

Hospital health care workers (HCW) are at increased risk of contracting SARS-CoV-2. We investigated whether certain behavioral and physical features, e.g. nose picking and wearing glasses, are associated with infection risk.

AIM

To assess the association between nose picking and related behavioral or physical features (nail biting, wearing glasses, and having a beard) and the incidence of SARS-CoV-2-infection.

METHODS

In a cohort study among 404 HCW in two university medical centers in the Netherlands, SARS-CoV-2-specific antibodies were prospectively measured during the first phase of the pandemic. For this study HCW received an additional retrospective survey regarding behavioral (e.g. nose picking) and physical features.

RESULTS

In total 219 HCW completed the survey (response rate 52%), and 34/219 (15.5%) became SARS-CoV-2 seropositive during follow-up from March 2020 till October 2020. The majority of HCW (185/219, 84.5%) reported picking their nose at least incidentally, with frequency varying between monthly, weekly and daily. SARS-CoV-2 incidence was higher in nose picking HCW compared to participants who refrained from nose picking (32/185: 17.3% vs. 2/34: 5.9%, OR 3.80, 95% CI 1.05 to 24.52), adjusted for exposure to COVID-19. No association was observed between nail biting, wearing glasses, or having a beard, and the incidence of SARS-CoV-2 infection.

CONCLUSION

Nose picking among HCW is associated with an increased risk of contracting a SARS-CoV-2 infection. We therefore recommend health care facilities to create more awareness, e.g. by educational sessions or implementing recommendations against nose picking in infection prevention guidelines.

Prolonged indoleamine 2,3-dioxygenase-2 activity and associated cellular stress in post-acute sequelae of SARS-CoV-2 infection

BACKGROUND

Post-acute sequela of SARS-CoV-2 infection (PASC) encompass fatigue, post-exertional malaise and cognitive problems. The abundant expression of the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase-2 (IDO2) in fatal/severe COVID-19, led us to determine, in an exploratory observational study, whether IDO2 is expressed and active in PASC, and may correlate with pathophysiology.

METHODS

Plasma or serum, and peripheral blood mononuclear cells (PBMC) were obtained from well-characterized PASC patients and SARS-CoV-2-infected individuals without PASC. We assessed tryptophan and its degradation products by UPLC-MS/MS. IDO2 activity, its potential consequences, and the involvement of the aryl hydrocarbon receptor (AHR) in IDO2 expression were determined in PBMC from another PASC cohort by immunohistochemistry (IHC) for IDO2, IDO1, AHR, kynurenine metabolites, autophagy, and apoptosis. These PBMC were also analyzed by metabolomics and for mitochondrial functioning by respirometry. IHC was also performed on autopsy brain material from two PASC patients.

FINDINGS

IDO2 is expressed and active in PBMC from PASC patients, as well as in brain tissue, long after SARS-CoV-2 infection. This is paralleled by autophagy, and in blood cells by reduced mitochondrial functioning, reduced intracellular levels of amino acids and Krebs cycle-related compounds. IDO2 expression and activity is triggered by SARS-CoV-2-infection, but the severity of SARS-CoV-2-induced pathology appears related to the generated specific kynurenine metabolites. Ex vivo, IDO2 expression and autophagy can be halted by an AHR antagonist.

INTERPRETATION

SARS-CoV-2 infection triggers long-lasting IDO2 expression, which can be halted by an AHR antagonist. The specific kynurenine catabolites may relate to SARS-CoV-2-induced symptoms and pathology.

FUNDING

None.

Recent infection with HCoV-OC43 may be associated with protection against SARS-CoV-2 infection

Antibodies against seasonal human coronaviruses (HCoVs) are known to cross-react with SARS-CoV-2, but data on cross-protective effects of prior HCoV infections are conflicting. In a prospective cohort of healthcare workers (HCWs), we studied the association between seasonal HCoV (OC43, HKU1, 229E and NL63) nucleocapsid protein IgG and SARS-CoV-2 infection during the first pandemic wave in the Netherlands (March 2020 - June 2020), by 4-weekly serum sampling. HCW with HCoV-OC43 antibody levels in the highest quartile, were less likely to become SARS-CoV-2 seropositive when compared with those with lower levels (6/32, 18.8%, versus 42/97, 43.3%, respectively: p = 0.019; HR 0.37, 95% CI 0.16-0.88). We found no significant association with HCoV-OC43 spike protein IgG, or with antibodies against other HCoVs. Our results indicate that the high levels of HCoV-OC43-nucleocapsid antibodies, as an indicator of a recent infection, are associated with protection against SARS-CoV-2 infection; this supports and informs efforts to develop pancoronavirus vaccines.

Antigenic cartography using sera from sequence-confirmed SARS-CoV-2 variants of concern infections reveals antigenic divergence of Omicron

Large-scale vaccination campaigns have prevented countless hospitalizations and deaths due to COVID-19. However, the emergence of SARS-CoV-2 variants that escape from immunity challenges the effectiveness of current vaccines. Given this continuing evolution, an important question is when and how to update SARS-CoV-2 vaccines to antigenically match circulating variants, similarly to seasonal influenza viruses where antigenic drift necessitates periodic vaccine updates. Here, we studied SARS-CoV-2 antigenic drift by assessing neutralizing activity against variants of concern (VOCs) in a set of sera from patients infected with viral sequence-confirmed VOCs. Infections with D614G or Alpha strains induced the broadest immunity, whereas individuals infected with other VOCs had more strain-specific responses. Omicron BA.1 and BA.2 were substantially resistant to neutralization by sera elicited by all other variants. Antigenic cartography revealed that Omicron BA.1 and BA.2 were antigenically most distinct from D614G, associated with immune escape, and possibly will require vaccine updates to ensure vaccine effectiveness.

Decreased Passive Immunity to Respiratory Viruses through Human Milk during the COVID-19 Pandemic

Infants may develop severe viral respiratory tract infections because their immune system is still developing in the first months after birth. Human milk provides passive humoral immunity during the first months of life. During the COVID-19 pandemic, circulation of common respiratory viruses was virtually absent due to the preventative measures resulting in reduced maternal exposure. Therefore, we hypothesized that this might result in lower antibody levels in human milk during the pandemic and, subsequently, decreased protection of infants against viral respiratory tract infections. We assessed antibody levels against respiratory syncytial virus (RSV), Influenza virus, and several seasonal coronaviruses in different periods of the COVID-19 pandemic in serum and human milk using a Luminex assay. IgG levels against RSV, Influenza, HCoV-OC43, HCoV-HKU1, and HCoV-NL63 in human milk were reduced with a factor of 1.7 (P < 0.001), 2.2 (P < 0.01), 2.6 (P < 0.05), 1.4 (P < 0.01), and 2.1 (P < 0.001), respectively, since the introduction of the COVID-19 restrictions. Furthermore, we observed that human milk of mothers that experienced COVID-19 contained increased levels of IgG and IgA binding to other respiratory viruses. Passive immunity via human milk against common respiratory viruses was reduced during the COVID-19 pandemic, which may have consequences for the protection of breastfed infants against respiratory infections. IMPORTANCE Passive immunity derived from antibodies in human milk is important for protecting young infants against invading viruses. During the COVID-19 pandemic, circulation of common respiratory viruses was virtually absent due to preventative measures. In this study, we observed a decrease in human milk antibody levels against common respiratory viruses several months into the COVID-19 pandemic. This waning of antibody levels might partially explain the previously observed surge of hospitalizations of infants, mostly due to RSV, when preventative hygiene measures were lifted. Knowledge of the association between preventative measures, antibody levels in human milk and subsequent passive immunity in infants might help predict infant hospital admissions and thereby enables anticipation to prevent capacity issues. Additionally, it is important in the consideration for strategies for future lockdowns to best prevent possible consequences for vulnerable infants.

Antibody responses against SARS-CoV-2 variants induced by four different SARS-CoV-2 vaccines in health care workers in the Netherlands: A prospective cohort study

BACKGROUND

Emerging and future SARS-CoV-2 variants may jeopardize the effectiveness of vaccination campaigns. Therefore, it is important to know how the different vaccines perform against diverse SARS-CoV-2 variants.

METHODS AND FINDINGS

In a prospective cohort of 165 SARS-CoV-2 naive health care workers in the Netherlands, vaccinated with either one of four vaccines (BNT162b2, mRNA-1273, AZD1222 or Ad26.COV2.S), we performed a head-to-head comparison of the ability of sera to recognize and neutralize SARS-CoV-2 variants of concern (VOCs; Alpha, Beta, Gamma, Delta and Omicron). Repeated serum sampling was performed 5 times during a year (from January 2021 till January 2022), including before and after booster vaccination with BNT162b2. Four weeks after completing the initial vaccination series, SARS-CoV-2 wild-type neutralizing antibody titers were highest in recipients of mRNA-1273, followed by recipients of BNT162b2 (geometric mean titers (GMT) of 358 [95% CI 231-556] and 214 [95% CI 153-299], respectively; p<0.05), and substantially lower in those vaccinated with the adenovirus vector-based vaccines AZD1222 and Ad26.COV2.S (GMT of 18 [95% CI 11-30] and 14 [95% CI 8-25] IU/ml, respectively; p<0.001). VOCs neutralization was reduced in all vaccine groups, with the greatest reduction in neutralization GMT observed against the Omicron variant (fold change 0.03 [95% CI 0.02-0.04], p<0.001). The booster BNT162b2 vaccination increased neutralizing antibody titers for all groups with substantial improvement against the VOCs including the Omicron variant. We used linear regression and linear mixed model analysis. All results were adjusted for possible confounding of age and sex. Study limitations include the lack of cellular immunity data.

CONCLUSIONS

Overall, this study shows that the mRNA vaccines appear superior to adenovirus vector-based vaccines in inducing neutralizing antibodies against VOCs four weeks after initial vaccination and after booster vaccination, which implies the use of mRNA vaccines for both initial and booster vaccination.

A single mRNA vaccine dose in COVID-19 patients boosts neutralizing antibodies against SARS-CoV-2 and variants of concern

The urgent need for, but limited availability of, SARS-CoV-2 vaccines worldwide has led to widespread consideration of dose-sparing strategies. Here, we evaluate the SARS-CoV-2-specific antibody responses following BNT162b2 vaccination in 150 previously SARS-CoV-2-infected individuals from a population-based cohort. One week after first vaccine dose, spike protein antibody levels are 27-fold higher and neutralizing antibody titers 12-fold higher, exceeding titers of fully vaccinated SARS-CoV-2-naive controls, with minimal additional boosting after the second dose. Neutralizing antibody titers against four variants of concern increase after vaccination; however, overall neutralization breadth does not improve. Pre-vaccination neutralizing antibody titers and time since infection have the largest positive effect on titers following vaccination. COVID-19 severity and the presence of comorbidities have no discernible impact on vaccine response. In conclusion, a single dose of BNT162b2 vaccine up to 15 months after SARS-CoV-2 infection offers higher neutralizing antibody titers than 2 vaccine doses in SARS-CoV-2-naive individuals.

Cross-reactive antibodies after SARS-CoV-2 infection and vaccination

Current SARS-CoV-2 vaccines are losing efficacy against emerging variants and may not protect against future novel coronavirus outbreaks, emphasizing the need for more broadly protective vaccines. To inform the development of a pan-coronavirus vaccine, we investigated the presence and specificity of cross-reactive antibodies against the spike (S) proteins of human coronaviruses (hCoV) after SARS-CoV-2 infection and vaccination. We found an 11- to 123-fold increase in antibodies binding to SARS-CoV and MERS-CoV as well as a 2- to 4-fold difference in antibodies binding to seasonal hCoVs in COVID-19 convalescent sera compared to pre-pandemic healthy donors, with the S2 subdomain of the S protein being the main target for cross-reactivity. In addition, we detected cross-reactive antibodies to all hCoV S proteins after SARS-CoV-2 vaccination in macaques and humans, with higher responses for hCoV more closely related to SARS-CoV-2. These findings support the feasibility of and provide guidance for development of a pan-coronavirus vaccine.

Cross-reactive antibodies after SARS-CoV-2 infection and vaccination

Current SARS-CoV-2 vaccines are losing efficacy against emerging variants and may not protect against future novel coronavirus outbreaks, emphasizing the need for more broadly protective vaccines. To inform the development of a pan-coronavirus vaccine, we investigated the presence and specificity of cross-reactive antibodies against the spike (S) proteins of human coronaviruses (hCoV) after SARS-CoV-2 infection and vaccination. We found an 11- to 123-fold increase in antibodies binding to SARS-CoV and MERS-CoV as well as a 2- to 4-fold difference in antibodies binding to seasonal hCoVs in COVID-19 convalescent sera compared to pre-pandemic healthy donors, with the S2 subdomain of the S protein being the main target for cross-reactivity. In addition, we detected cross-reactive antibodies to all hCoV S proteins after SARS-CoV-2 vaccination in macaques and humans, with higher responses for hCoV more closely related to SARS-CoV-2. These findings support the feasibility of and provide guidance for development of a pan-coronavirus vaccine.

Time since SARS-CoV-2 infection and humoral immune response following BNT162b2 mRNA vaccination

BACKGROUND

To optimise the use of available SARS-CoV-2 vaccines, some advocate delaying second vaccination for individuals infected within six months. We studied whether post-vaccination immune response is equally potent in individuals infected over six months prior to vaccination.

METHODS

We tested serum IgG binding to SARS-CoV-2 spike protein and neutralising capacity in 110 healthcare workers, before and after both BNT162b2 messenger RNA (mRNA) vaccinations. We compared outcomes between participants with more recent infection (n = 18, median two months, IQR 2-3), with infection-vaccination interval over six months (n = 19, median nine months, IQR 9-10), and to those not previously infected (n = 73).

FINDINGS

Both recently and earlier infected participants showed comparable humoral immune responses after a single mRNA vaccination, while exceeding those of previously uninfected persons after two vaccinations with 2.5 fold (p = 0.003) and 3.4 fold (p < 0.001) for binding antibody levels, and 6.4 and 7.2 fold for neutralisation titres, respectively (both p < 0.001). The second vaccine dose yielded no further substantial improvement of the humoral response in the previously infected participants (0.97 fold, p = 0.92), while it was associated with a 4 fold increase in antibody binding levels and 18 fold increase in neutralisation titres in previously uninfected participants (both p < 0.001). Adjustment for potential confounding of sex and age did not affect these findings.

INTERPRETATION

Delaying the second vaccination in individuals infected up to ten months prior may constitute a more efficient use of limited vaccine supplies.

FUNDING

Netherlands Organization for Health Research and Development ZonMw; Corona Research Fund Amsterdam UMC; Bill & Melinda Gates Foundation.

Emerging SARS-CoV-2 variants of concern evade humoral immune responses from infection and vaccination

Emerging SARS-CoV-2 variants of concern (VOCs) pose a threat to human immunity induced by natural infection and vaccination. We assessed the recognition of three VOCs (B.1.1.7, B.1.351, and P.1) in cohorts of COVID-19 convalescent patients (n = 69) and Pfizer-BioNTech vaccine recipients (n = 50). Spike binding and neutralization against all three VOCs were substantially reduced in most individuals, with the largest four- to sevenfold reduction in neutralization being observed against B.1.351. While hospitalized patients with COVID-19 and vaccinees maintained sufficient neutralizing titers against all three VOCs, 39% of nonhospitalized patients exhibited no detectable neutralization against B.1.351. Moreover, monoclonal neutralizing antibodies show sharp reductions in their binding kinetics and neutralizing potential to B.1.351 and P.1 but not to B.1.1.7. These data have implications for the degree to which pre-existing immunity can protect against subsequent infection with VOCs and informs policy makers of susceptibility to globally circulating SARS-CoV-2 VOCs.

Serologic Surveillance and Phylogenetic Analysis of SARS-CoV-2 Infection Among Hospital Health Care Workers

IMPORTANCE

It is unclear when, where, and by whom health care workers (HCWs) working in hospitals are infected with SARS-CoV-2.

OBJECTIVE

To determine how often and in what manner nosocomial SARS-CoV-2 infection occurs in HCW groups with varying exposure to patients with COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study comprised 4 weekly measurements of SARS-CoV-2-specific antibodies and collection of questionnaires from March 23 to June 25, 2020, combined with phylogenetic and epidemiologic transmission analyses at 2 university hospitals in the Netherlands. Included individuals were HCWs working in patient care for those with COVID-19, HCWs working in patient care for those without COVID-19, and HCWs not working in patient care. Data were analyzed from August through December 2020.

EXPOSURES

Varying work-related exposure to patients infected with SARS-CoV-2.

MAIN OUTCOMES AND MEASURES

The cumulative incidence of and time to SARS-CoV-2 infection, defined as the presence of SARS-CoV-2-specific antibodies in blood samples, were measured.

RESULTS

Among 801 HCWs, there were 439 HCWs working in patient care for those with COVID-19, 164 HCWs working in patient care for those without COVID-19, and 198 HCWs not working in patient care. There were 580 (72.4%) women, and the median (interquartile range) age was 36 (29-50) years. The incidence of SARS-CoV-2 was increased among HCWs working in patient care for those with COVID-19 (54 HCWs [13.2%; 95% CI, 9.9%-16.4%]) compared with HCWs working in patient care for those without COVID-19 (11 HCWs [6.7%; 95% CI, 2.8%-10.5%]; hazard ratio [HR], 2.25; 95% CI, 1.17-4.30) and HCWs not working in patient care (7 HCWs [3.6%; 95% CI, 0.9%-6.1%]; HR, 3.92; 95% CI, 1.79-8.62). Among HCWs caring for patients with COVID-19, SARS-CoV-2 cumulative incidence was increased among HCWs working on COVID-19 wards (32 of 134 HCWs [25.7%; 95% CI, 17.6%-33.1%]) compared with HCWs working on intensive care units (13 of 186 HCWs [7.1%; 95% CI, 3.3%-10.7%]; HR, 3.64; 95% CI, 1.91-6.94), and HCWs working in emergency departments (7 of 102 HCWs [8.0%; 95% CI, 2.5%-13.1%]; HR, 3.29; 95% CI, 1.52-7.14). Epidemiologic data combined with phylogenetic analyses on COVID-19 wards identified 3 potential HCW-to-HCW transmission clusters. No patient-to-HCW transmission clusters could be identified in transmission analyses.

CONCLUSIONS AND RELEVANCE

This study found that HCWs working on COVID-19 wards were at increased risk for nosocomial SARS-CoV-2 infection with an important role for HCW-to-HCW transmission. These findings suggest that infection among HCWs deserves more consideration in infection prevention practice.

Emerging SARS-CoV-2 variants of concern evade humoral immune responses from infection and vaccination

Emerging SARS-CoV-2 variants pose a threat to human immunity induced by natural infection and vaccination. We assessed the recognition of three variants of concern (B.1.1.7, B.1.351 and P.1) in cohorts of COVID-19 patients ranging in disease severity (n = 69) and recipients of the Pfizer/BioNTech vaccine (n = 50). Spike binding and neutralization against all three VOC was substantially reduced in the majority of samples, with the largest 4-7-fold reduction in neutralization being observed against B.1.351. While hospitalized COVID-19 patients and vaccinees maintained sufficient neutralizing titers against all three VOC, 39% of non-hospitalized patients did not neutralize B.1.351. Moreover, monoclonal neutralizing antibodies (NAbs) show sharp reductions in their binding kinetics and neutralizing potential to B.1.351 and P.1, but not to B.1.1.7. These data have implications for the degree to which pre-existing immunity can protect against subsequent infection with VOC and informs policy makers of susceptibility to globally circulating SARS-CoV-2 VOC.

[Research into diagnostic reasoning: significant, but also relevant?]

Research into diagnostic reasoning often focuses on diagnostic errors, while ignoring the also important concepts of overdiagnosis and cost of the diagnostic process. A popular theoretic model guiding studies on the subject is the dual process model in which cognitive errors play an important role. This paradigm is also used in the study of Mamede and colleagues, who studied the effect of disease specific knowledge on the occurrence of diagnostic errors due to availability bias in internal medicine residents. The study, which used case vignettes, is well set up but its experimental design cannot account for the influence of clinical context which limits its clinical value. Further research into this topic should be performed in actual clinical situations to provide more insight in how to improve diagnostic reasoning in medicine.

Outcomes of persons with coronavirus disease 2019 in hospitals with and without standard treatment with (hydroxy)chloroquine

Objective

To compare survival of individuals with coronavirus disease 2019 (COVID-19) treated in hospitals that either did or did not routinely treat patients with hydroxychloroquine or chloroquine.

Methods

We analysed data of COVID-19 patients treated in nine hospitals in the Netherlands. Inclusion dates ranged from 27 February to 15 May 2020, when the Dutch national guidelines no longer supported the use of (hydroxy)chloroquine. Seven hospitals routinely treated patients with (hydroxy)chloroquine, two hospitals did not. Primary outcome was 21-day all-cause mortality. We performed a survival analysis using log-rank test and Cox regression with adjustment for age, sex and covariates based on premorbid health, disease severity and the use of steroids for adult respiratory distress syndrome, including dexamethasone.

Results

Among 1949 individuals, 21-day mortality was 21.5% in 1596 patients treated in hospitals that routinely prescribed (hydroxy)chloroquine, and 15.0% in 353 patients treated in hospitals that did not. In the adjusted Cox regression models this difference disappeared, with an adjusted hazard ratio of 1.09 (95% CI 0.81–1.47). When stratified by treatment actually received in individual patients, the use of (hydroxy)chloroquine was associated with an increased 21-day mortality (HR 1.58; 95% CI 1.24–2.02) in the full model.

Conclusions

After adjustment for confounders, mortality was not significantly different in hospitals that routinely treated patients with (hydroxy)chloroquine compared with hospitals that did not. We compared outcomes of hospital strategies rather than outcomes of individual patients to reduce the chance of indication bias. This study adds evidence against the use of (hydroxy)chloroquine in hospitalised patients with COVID-19.

E-learning on antibiotic prescribing-the role of autonomous motivation in participation: a prospective cohort study

Objectives

E-learning is increasingly used in education on antimicrobial stewardship, but participation rates are often low. Insight into factors that affect participation is therefore needed. Autonomous motivation is associated with higher achievements in medical education and could also play a role in e-learning participation. We therefore aimed to investigate the role of residents’ autonomous motivation in their participation in e-learning on antibiotic prescribing.

Methods

We performed a multicentre cohort study in two academic and two teaching hospitals. Residents who filled out questionnaires on antibiotic knowledge, the perceived importance of antibiotics and motivation [Self-Regulation Questionnaire – Academic (SRQ-a)] received e-learning access. We used the SRQ-a to calculate relative autonomous motivation (RAM), an index that estimates the amount of autonomous motivation compared with the amount of controlled motivation. We then analysed associations between RAM and participation in e-learning with logistic regression.

Results

Eighty-six residents participated (74% female, mean age 30 years). Overall e-learning participation was 58% (n = 50). Participation was 41% in residents with negative RAM (i.e. more controlled motivation) and 62% in residents with positive RAM (i.e. more autonomous motivation). RAM was positively associated with participation, adjusted for residency in an academic hospital (adjusted OR 2.6, 95% CI 1.5–4.6).

Conclusions

Participation in non-obligatory e-learning on antibiotic prescribing is higher in residents with more autonomous motivation. Interventions to increase autonomous motivation could improve participation. Preceding e-learning on antibiotic prescribing with face-to-face education, to explain the importance of the subject, could enhance autonomous motivation and thus optimize e-learning efficiency.

Improving antibiotic prescribing skills in medical students: the effect of e-learning after 6 months

Background

Antimicrobial prescribing behaviour is first established during medical study, but teachers often cite lack of time as an important problem in the implementation of antimicrobial stewardship in the medical curriculum. The use of electronic learning (e-learning) is a potentially time-efficient solution, but its effectiveness in changing long-term prescribing behaviour in medical students is as yet unknown.

Methods

We performed a prospective controlled intervention study of the long-term effects of a short interactive e-learning course among fourth year medical students in a Dutch university. The e-learning was temporarily implemented as a non-compulsory course during a 6 week period. Six months later, all students underwent an infectious disease-based objective structured clinical examination (OSCE) aimed at simulating postgraduate prescribing. If they passed, each student did the OSCE only once. We created a control group of students from a period when the e-learning was not implemented. Main outcomes were the OSCE pass percentage and knowledge, drug choice and overall scores. We used propensity scores to create equal comparisons.

Results

We included 71 students in the intervention group and 285 students in the control group. E-learning participation in the intervention group was 81%. The OSCE pass percentage was 86% in the control group versus 97% in the intervention group (+11%, OR 5.9, 95% CI 1.7-20.0). OSCE overall, knowledge and drug choice grades (1-10) were also significantly higher in the intervention group (differences +0.31, +0.31 and +0.51, respectively).

Conclusions

E-learning during a limited period can significantly improve medical students' performance of an antimicrobial therapeutic consultation in a situation simulating clinical practice 6 months later.

The 'morning dip' in antimicrobial appropriateness: circumstances determining appropriateness of antimicrobial prescribing

Objectives

Quality of care has been shown to vary depending on the time of day or day of the week and depending on caregivers' gender and experience. We aimed to study how these factors influence quality of antimicrobial prescribing.

Methods

Prospective point-prevalence surveys were performed to determine the association between the above-mentioned prescription factors and antimicrobial appropriateness. Surveys included cases of patients admitted to a tertiary care hospital with a prescribed systemic antimicrobial drug and its prescribers. The main outcome was appropriateness of antimicrobial prescriptions. A post hoc qualitative survey among hospital physicians asked physicians to reflect on the results.

Results

The study included 351 antimicrobial prescriptions by 150 physicians prescribed for 276 patients. Appropriateness of antimicrobial prescribing in the morning was significantly lower compared with the afternoon and evening/night [43% versus 68% versus 70%, crude OR afternoon versus morning = 3.00 (95% CI = 1.60-5.48), crude OR evening/night versus morning = 3.40 (95% CI = 1.64-6.69)]. First-year residents performed significantly worse than their more experienced colleagues [51% versus 69%, crude OR = 2.09 (95% CI = 1.26-3.38)]. Infectious disease expert consultation improved appropriateness [54% versus 81%, crude OR = 3.71 (95% CI = 2.05-6.23)]. No significant effects for gender or office hours versus non-office hours were found. Post hoc survey results suggest creating room to improve prescribing circumstances during mornings and for inexperienced physicians.

Conclusions

Antimicrobial prescribing was less appropriate in the mornings and when prescribed by inexperienced physicians. Appropriateness may be increased by improving prescribing circumstances.

The impact of laboratory closing times on delay of adequate therapy in blood stream infections

BACKGROUND

Patients with bloodstream infections need early adequate antimicrobial treatment to reduce mortality. This raises the question of timing and logistics. How important is the time of day when a culture is flagged positive to the processing of blood cultures and optimisation of antimicrobial therapy?

METHODS

We performed a retrospective study assessing the time delay of a positive blood culture result during and after office hours and its impact on adequate antimicrobial therapy. Process duration from the moment of culture positivity to Gram stain completion was compared at different timepoints during the day in a medium-sized hospital with an offsite microbiological laboratory.

RESULTS

Ninety-four patients with positive, noncontaminated blood cultures were included. Sixty-six patients (70%) received adequate empirical therapy; this increased to 76 cases (82%) and to 88 cases (95%) after analysis of Gram stain results and complete determination, respectively (p < 0.05 for all comparisons). Median duration from culture positivity to Gram stain completion (including offsite culture transport) increased from a median of four to 12 hours if time of cultures turned positive after office hours (p < 0.05), irrespective of the adequacy of empirical coverage. This also resulted in a median 12-hour delay for the complete process from time of culture positivity to administration of the antimicrobial drug (p < 0.05).

CONCLUSION

Processing blood cultures after office hours is often deferred, which can lead to a delay in adequate antimicrobial therapy for patients with bloodstream infections.

Behavioral Approach to Appropriate Antimicrobial Prescribing in Hospitals: The Dutch Unique Method for Antimicrobial Stewardship (DUMAS) Participatory Intervention Study

Importance

Inappropriate antimicrobial prescribing leads to antimicrobial resistance and suboptimal clinical outcomes. Changing antimicrobial prescribing is a complex behavioral process that is not often taken into account in antimicrobial stewardship programs.

Objective

To examine whether an antimicrobial stewardship approach grounded in behavioral theory and focusing on preserving prescriber autonomy and participation is effective in improving appropriateness of antimicrobial prescribing in hospitals.

Design, Setting, and Participants

The Dutch Unique Method for Antimicrobial Stewardship (DUMAS) study was a prospective, stepped-wedge, participatory intervention study performed from October 1, 2011, through December 31, 2015. Outcomes were measured during a baseline period of 16 months and an intervention period of 12 months. The study was performed at 7 clinical departments (2 medical, 3 surgical, and 2 pediatric) in a tertiary care medical center and a general teaching hospital in the Netherlands. Physicians prescribing systemic antimicrobial drugs for any indication for patients admitted to the participating departments during the study period were included in the study.

Interventions

We offered prescribers a free choice of how to improve their antimicrobial prescribing. Prescribers were stimulated to choose interventions with higher potential for success based on a root cause analysis of inappropriate prescribing.

Main Outcomes and Measures

Appropriateness of antimicrobial prescriptions was determined using a validated approach based on guideline adherence and motivated guideline deviation and measured with repeated point prevalence surveys (6 per year). Appropriateness judgment was masked for the study period. Antimicrobial consumption was extracted from pharmacy records and measured as days of therapy per admission. We used linear and logistic mixed-model regression analysis to model outcomes over time.

Results

A total of 1121 patient cases with 700 antimicrobial prescriptions were assessed during the baseline period and 882 patient cases with 531 antimicrobial prescriptions during the intervention period. The mean antimicrobial appropriateness increased from 64.1% at intervention start to 77.4% at 12-month follow-up (+13.3%; relative risk, 1.17; 95% CI, 1.04-1.27), without a change in slope. No decrease in antimicrobial consumption was found.

Conclusions and Relevance

Use of a behavioral approach preserving prescriber autonomy resulted in an increase in antimicrobial appropriateness sustained for at least 12 months. The approach is inexpensive and could be easily transferable to various health care environments.

Assessment of appropriate antimicrobial prescribing: do experts agree?

OBJECTIVES

Little is known about the validity and reliability of expert assessments of the quality of antimicrobial prescribing, despite their importance in antimicrobial stewardship. We investigated how infectious disease doctors' assessments compared with a reference standard (modal expert opinion) and with the assessments of their colleagues.

METHODS

Twenty-four doctors specialized in infectious diseases or clinical microbiology (16 specialists and 8 residents) from five hospitals were asked to assess the appropriateness of antimicrobial agents prescribed for a broad spectrum of indications in 56 paper cases. They were instructed how to handle guideline applicability and deviations. We created a reference standard of antimicrobial appropriateness using the modal assessment of 16 specialists. We calculated criterion validity and interrater and intrarater overall and specific agreement with an index expert (senior infectious disease physician) and analysed the influence of doctor characteristics on validity.

RESULTS

Specialists agreed with the reference standard in 80% of cases (range 75%-86%), with a sensitivity and specificity of 75% and 84%, respectively. This did not differ by clinical specialty, hospital or years of experience, and residents had similar results. Specialists agreed with the index expert in 76% of cases and the index expert agreed with his previous assessments in 71% of cases.

CONCLUSIONS

Doctors specialized in infectious diseases and clinical microbiology assess the appropriateness of antimicrobials prescribed for a broad spectrum of indications with acceptable agreement and validity, regardless of their experience or hospital of employment. However, there is room for improvement, which merits attention in multidisciplinary discussions and education.

Stay tuned: what is special about not shifting attention?

Background

When studying attentional orienting processes, brain activity elicited by symbolic cue is usually compared to a neutral condition in which no information is provided about the upcoming target location. It is generally assumed that when a neutral cue is provided, participants do not shift their attention. The present study sought to validate this assumption. We further investigated whether anticipated task demands had an impact on brain activity related to processing symbolic cues.

Methodology/Principal Findings

Two experiments were conducted, during which event-related potentials were elicited by symbolic cues that instructed participants to shift their attention to a particular location on a computer screen. In Experiment 1, attention shift-inducing cues were compared to non-informative cues, while in both conditions participants were required to detect target stimuli that were subsequently presented at peripheral locations. In Experiment 2, a non-ambiguous “stay-central” cue that explicitly required participants not to shift their attention was used instead. In the latter case, target stimuli that followed a stay-central cue were also presented at a central location. Both experiments revealed enlarged early latency contralateral ERP components to shift-inducing cues compared to those elicited by either non-informative (exp. 1) or stay-central cues (exp. 2). In addition, cueing effects were modulated by the anticipated difficulty of the upcoming target, particularly so in Experiment 2. A positive difference, predominantly over the posterior contralateral scalp areas, could be observed for stay-central cues, especially for those predicting that the upcoming target would be easy. This effect was not present for non-informative cues.

Conclusions/Significance

We interpret our result in terms of a more rapid engagement of attention occurring in the presence of a more predictive instruction (i.e. stay-central easy target). Our results indicate that the human brain is capable of very rapidly identifying the difference between different types of instructions.

[Congenital anomalies in Amsterdam: results of the 'Amsterdam-Born Children and their Development' study]

OBJECTIVE

To describe the prevalence of congenital anomalies in children born in Amsterdam and to analyse potential differences between groups based on risk factors such as ethnicity and maternal age.

DESIGN

Secondary analysis of a prospective cohort study.

METHODS

Between 2003 and 2004, mothers filled in questionnaires on their newborn children on behalf of the Amsterdam-Born Children and their Development study (ABCD study). Data from 5,276 liveborn children in this cohort were used to calculate the prevalence rates of congenital anomalies in Amsterdam. These were compared with expected prevalence rates based on Eurocat data for the Northern region of the Netherlands during the years 2000-2005. Prevalence rates were compared between subgroups which had been divided according to risk factors: maternal ethnic origin, maternal age, parity, gender of child, inter-pregnancy interval, years of maternal education, smoking, alcohol use, and periconceptional folate use.

RESULTS

The total prevalence of major congenital anomalies among liveborn children in the ABCD cohort was as expected based on the figures from the Eurocat registration. Digestive anomalies were reported significantly less frequently (n = 1) than expected (n = 10). Mothers of Surinam descent more frequently reported a child with a musculoskeletal anomaly. Older mothers were more likely to report congenital anomalies. No significant trends regarding other risk factors were observed.

CONCLUSIONS

No significant trends regarding ethnicity and congenital anomalies were detected. The interpretation of the other results was hampered by methodological differences between the ABCD study and Eurocat. Nationwide registration with active case detection of congenital anomalies is therefore recommended.

[Orphanet: a European database for rare diseases]

Orphanet is a European initiative that aims to improve the management and treatment of rare diseases. It comprises a database dedicated to information on rare diseases and orphan drugs, and offers services adapted to the needs of patients and their families, health professionals, and researchers. The database can be accessed through the website (www.orpha.net) and has some interesting options for searching, for example research projects, support groups or searching by clinical signs. Health professionals are encouraged to add activities concerning rare diseases to the database.