A Single Dose of BNT162b2 mRNA Vaccine Induces Airway Immunity in SARS-CoV-2 Naive and recovered COVID-19 subjects.

BACKGROUND: Mucosal antibodies can prevent virus entry and replication in mucosal epithelial cells and hence virus shedding. Parenteral booster injection of a vaccine against a mucosal pathogen promotes stronger mucosal immune responses following prior mucosal infection compared to injections of a parenteral vaccine in a mucosally naive subject. We investigated whether this was also the case for the BNT162b2 COVID-19 mRNA vaccine. METHODS: Twenty recovered COVID-19 subjects (RCS) and 23 SARS-CoV-2 naive subjects were vaccinated with respectively one and two doses of the BNT162b2 COVID-19 vaccine. Nasal Epithelial Lining Fluid (NELF) and plasma were collected before and after vaccination and assessed for Immunoglobulin (Ig)G and IgA antibody levels to Spike and for their ability to neutralize binding of Spike to ACE-2 receptor. Blood was analyzed one week after vaccination for the number of Spike-specific Antibody Secreting Cells (ASCs) with a mucosal tropism. RESULTS: All RCS had both nasal and blood SARS-CoV-2 specific antibodies at least 90 days after initial diagnosis. In RCS, a single dose of vaccine amplified pre-existing Spike-specific IgG and IgA antibody responses in both NELF and blood against both vaccine homologous and variant strains, including delta. These responses were associated with Spike-specific IgG and IgA ASCs with a mucosal tropism in blood. Nasal IgA and IgG antibody responses were lower in magnitude in SARS-CoV-2 naive subjects after two vaccine doses compared to RCS after one dose. CONCLUSION: Mucosal immune response to the SARS-CoV-2 Spike protein is higher in RCS after a single vaccine dose compared to SARS-CoV-2 naive subjects after two doses.

Emergency Department Visits for Firearm Injuries Before and During the COVID-19 Pandemic - United States, January 2019-December 2022.

During the COVID-19 pandemic, the U.S. firearm homicide rate increased by nearly 35%, and the firearm suicide rate remained high during 2019-2020 (1). Provisional mortality data from the National Vital Statistics System indicate that rates continued to increase in 2021: the rates of firearm homicide and firearm suicide in 2021 were the highest recorded since 1993 and 1990, respectively (2). Firearm injuries treated in emergency departments (EDs), the primary setting for the immediate medical treatment of such injuries, gradually increased during 2018-2019 (3); however, more recent patterns of ED visits for firearm injuries, particularly during the COVID-19 pandemic, are unknown. Using data from the National Syndromic Surveillance Program (NSSP),* CDC examined changes in ED visits for initial firearm injury encounters during January 2019-December 2022, by year, patient sex, and age group. Increases in the overall weekly number of firearm injury ED visits were detected at certain periods during the COVID-19 pandemic. One such period during which there was a gradual increase was March 2020, which coincided with both the declaration of COVID-19 as a national emergency† and a pronounced decrease in the total number of ED visits. Another increase in firearm injury ED visits occurred in late May 2020, concurrent with a period marked by public outcry related to social injustice and structural racism (4), changes in state-level COVID-19-specific prevention strategies,§ decreased engagement in COVID-19 mitigation behaviors (5), and reported increases in some types of crime (4). Compared with 2019, the average number of weekly ED visits for firearm injury was 37% higher in 2020, 36% higher in 2021, and 20% higher in 2022. A comprehensive approach is needed to prevent and respond to firearm injuries in communities, including strategies that engage community and street outreach programs, implement hospital-based violence prevention programs, improve community physical environments, enhance secure storage of firearms, and strengthen social and economic supports.

SARS-CoV-2 Vaccination-Induced Immunogenicity in Heart Transplant Recipients.

Among heart transplant (HT) recipients, a reduced immunological response to SARS-CoV-2 vaccination has been reported. We aimed to assess the humoral and T-cell response to SARS-CoV-2 vaccination in HT recipients to understand determinants of immunogenicity. HT recipients were prospectively enrolled from January 2021 until March 2022. Anti-SARS-CoV-2-Spike IgG levels were quantified after two and three doses of a SARS-CoV-2 vaccine (BNT162b2, mRNA1273, or AZD1222). Spike-specific T-cell responses were assessed using flow cytometry. Ninety-one patients were included in the study (69% male, median age 55 years, median time from HT to first vaccination 6.1 years). Seroconversion rates were 34% after two and 63% after three doses. Older patient age (p = 0.003) and shorter time since HT (p = 0.001) were associated with lower antibody concentrations after three vaccinations. There were no associations between vaccine types or immunosuppressive regimens and humoral response, except for prednisolone, which was predictive of a reduced response after two (p = 0.001), but not after three doses (p = 0.434). A T-cell response was observed in 50% after two and in 74% after three doses. Despite three vaccine doses, a large proportion of HT recipients exhibits a reduced immune response. Additional strategies are desirable to improve vaccine immunogenicity in this vulnerable group of patients.

Effecting behaviour change using an artificial intelligence chatbot: A pilot randomised controlled study (preprint)

Chatbots have the potential to effect large-scale behaviour change because they are accessible through social media, flexible, scalable, and automatically gather data. Yet research on the feasibility and effectiveness of chatbot-administered behaviour change interventions is sparse. There is no guarantee that established behaviour change interventions are effective when implemented in chatbots given the unique human-machine interaction dynamics. In this pilot study, we test whether an advanced, natural language processing-based chatbot can effect behaviour change using animations embedded in conversations with users. Specifically, we evaluated whether the chatbot could increase understanding and intentions to adopt protective behaviours during the pandemic in a real world cohort. We randomised 59 participants from culturally and linguistically diverse populations to three groups, receiving either a compassion intervention, an exponential growth intervention or no intervention. We measured participants’ attitudes about leaving the house for different reasons and their intentions to get tested if they experienced symptoms. We found that the chatbot reduced uncertainty about appropriate COVID-19 protective behaviours and that the exponential growth bias intervention increased participants’ likelihood of getting tested. This study provides preliminary evidence that chatbots augmented with animations can spark behaviour change, with potential for applications in diverse and underrepresented groups, highlighting the need for further research on this topic.

[The Importance of Cost Structure for the Effectiveness of State Aid]. / Die Bedeutung der Kostenstruktur für die Effektivität von Staatshilfen.

For many firms, the coronavirus crisis has lead to persistent sales slumps that generated urgent liquidity demand - unless fixed costs were reduced. The authors use a newly developed classification procedure that makes the cost structure of companies and, thus, their sensitivity to sales shocks visible. This is useful for designing effective relief measures that preserve corporate structures by protecting employment and avoiding insolvencies of companies with healthy prospects for a recovery during the post-crisis period. Such an approach helps to accelerate economic recovery.

Vital Signs: Changes in Firearm Homicide and Suicide Rates - United States, 2019-2020.

INTRODUCTION: The majority of homicides (79%) and suicides (53%) in the United States involved a firearm in 2020. High firearm homicide and suicide rates and corresponding inequities by race and ethnicity and poverty level represent important public health concerns. This study examined changes in firearm homicide and firearm suicide rates coinciding with the emergence of the COVID-19 pandemic in 2020. METHODS: National vital statistics and population data were integrated with urbanization and poverty measures at the county level. Population-based firearm homicide and suicide rates were examined by age, sex, race and ethnicity, geographic area, level of urbanization, and level of poverty. RESULTS: From 2019 to 2020, the overall firearm homicide rate increased 34.6%, from 4.6 to 6.1 per 100,000 persons. The largest increases occurred among non-Hispanic Black or African American males aged 10-44 years and non-Hispanic American Indian or Alaska Native (AI/AN) males aged 25-44 years. Rates of firearm homicide were lowest and increased least at the lowest poverty level and were higher and showed larger increases at higher poverty levels. The overall firearm suicide rate remained relatively unchanged from 2019 to 2020 (7.9 to 8.1); however, in some populations, including AI/AN males aged 10-44 years, rates did increase. CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: During the COVID-19 pandemic, the firearm homicide rate in the United States reached its highest level since 1994, with substantial increases among several population subgroups. These increases have widened disparities in rates by race and ethnicity and poverty level. Several increases in firearm suicide rates were also observed. Implementation of comprehensive strategies employing proven approaches that address underlying economic, physical, and social conditions contributing to the risks for violence and suicide is urgently needed to reduce these rates and disparities.

Multisystem Inflammatory Syndrome Associated With Severe Acute Respiratory Syndrome Coronavirus 2 in Children: A Case Series From Mayotte Island.

During the COVID-19 outbreak in the French overseas department Mayotte, 11 children developed multisystem inflammatory syndrome (MIS-C). They all had a fever and gastrointestinal symptoms. Six patients were admitted to intensive care unit; management included intravenous immunoglobulin and corticosteroid. Severe acute respiratory syndrome coronavirus 2 was documented in all patients. The risk of developing MIS-C was much higher than in all of France.

Risk perception, illusory superiority, and personal responsibility during COVID-19: An experimental study of attitudes to staying home (preprint)

Individual decision-making about social distancing, self-quarantine and self-isolation is crucial in managing the COVID-19 pandemic. In the rapidly evolving pandemic, little is known about how different government communication strategies may systematically affect people’s attitudes to staying home or going out, nor the extent to which people perceive and process the risk of different scenarios. In this study, we report results from a sample of 581 participants (residing in the United Kingdom), and we examine the degree to which participants’ attitudes regarding the permissibility of leaving one’s home are (1) sensitive to different levels of risk of viral transmission in specific scenarios, (2) sensitive to communication framings that are either imperative or that invite reasoning about scenarios, or (3) creating “loopholes” for themselves when scenarios are framed with reference to the participants themselves rather than in general terms. We find that participants’ attitudes to social distancing are sensitive to the level of risk of transmission, and that when scenarios are framed in imperative terms, rather than when their reasoning is encouraged, participants have more impermissive attitudes to going out in Minimal Risk scenarios, with a trend of decreased permissiveness more generally; for self-loopholes, more research is needed to determine if participants make exceptions for themselves. Thus, subject to the limitations of this study, during phases where it is important to promote self-isolation for all scenarios, including those perceived to be low risk, imperative communication may be best.