Factors associated with meningitis vaccine awareness and engagement among Latino men who have sex with men in South Florida.

Awareness and uptake of the meningitis vaccine remains low among marginalized groups, such as Latino men who have sex with men (LMSM), potentially due to structural and psychosocial barriers in accessing preventative healthcare. The current study explored awareness and uptake of meningitis vaccines among a group of LMSM (N = 99) living in South Florida. A three-pronged variable selection approach was utilized prior to conducting regression models (linear and logistic). Overall, 48.5% of the participants reported little to no knowledge about meningitis vaccines, and 20.2% reported being vaccinated. Living with HIV (OR = 10.48) and time since outbreak (OR = 1.03) were significant predictors of meningitis vaccine uptake. No significant correlates of meningitis vaccine awareness were identified. More research is needed to identify other important factors associated with meningitis vaccine awareness and uptake among LMSM, a multiple marginalized group.

Government responses to the COVID-19 pandemic of the Gulf Cooperation Council countries: good practices and lessons for future preparedness.

The COVID-19 pandemic has dramatically threatened the Gulf Cooperation Council (GCC) countries which have a large proportion of foreign workers. The governments of GCC countries have proactively implemented a comprehensive set of policy measures, and up to our knowledge, a systematic analysis of qualitative and quantitative evidence on the government response is still lacking. We summarized the GCC countries' government response and quantitatively measured that response using four indexes-the Government Response Index, the Stringency Index, the Vaccine Index, and the Initial Response Index, to analyse their response for future pandemic preparedness. Overall, the government response of all the GCC countries to the COVID-19 pandemic has been comprehensive, stringent, and timely. Notably, the GCC countries have implemented comprehensive vaccine policies. In addition, they have worked actively to protect foreign workers to improve their access to health services and secure their essential living conditions, regardless of their immigrant status. All the GCC countries dynamically adjusted their response to the evolving COVID-19 epidemiological burden and started to relax the stringency of the control policies after the Omicron wave, though the governments had different response magnitudes as measured by the four indexes. These findings have provided several important lessons for future pandemic response and preparedness for countries with similar economic, demographic, and health contexts in (1) prompt actions of containment and closure policies with dynamic adjusting, (2) strengthening health system policies, (3) comprehensive vaccination policies with universal access, (4) equitable and free access to testing, diagnosis, and treatment for all, and (5) strengthening the resilience of health systems.

"Your Package Could Not Be Delivered": The State of Digital HIV Intervention Implementation in the US.

PURPOSE OF REVIEW: Despite continuous innovations and federal investment to create digital interventions addressing the HIV prevention and care continua, these interventions have not reached people in the U.S. at scale. This article reviews what is known about U.S. implementation of digital HIV interventions and presents a strategy to cross the research-to-practice chasm for these types of interventions. RECENT FINDINGS: We conducted a narrative review of U.S.-based original research on implementation of digital HIV interventions and identified few studies reporting on implementation determinants, strategies, processes, or outcomes, particularly outside the context of effectiveness trials. To supplement the literature, in 2023, we surveyed 47 investigators representing 64 unique interventions about their experiences with implementation after their research trials. Respondents placed high importance on intervention implementation, but major barriers included lack of funding and clear implementation models, technology costs, and difficulty identifying partners equipped to deliver digital interventions. They felt that responsibility for implementation should be shared between intervention developers, deliverers (e.g., clinics), and a government entity. If an implementation center were to exist, most respondents wanted to be available for guidance or technical assistance but largely wanted less involvement. Numerous evidence-based, effective digital interventions exist to address HIV prevention and care. However, they remain "on the shelf" absent a concrete and sustainable model for real-world dissemination and implementation. Based on our findings, we call for the creation of national implementation centers, analogous to those in other health systems, to facilitate digital HIV intervention delivery and accelerate progress toward ending the U.S. epidemic.

Peer ambassador stories: formative qualitative research to enhance the reach of PrEP, HIV testing, and behavioral health treatments to LMSM in South Florida.

Existing HIV prevention interventions, such as pre-exposure prophylaxis (PrEP), and behavioral health treatments inadequately reach Latino men who have sex with men (LMSM) in the US. This study involved formative research to inform the content, design, and implementation of a scalable, low resource implementation strategy - peer ambassador stories - stories from peers to normalize using PrEP, HIV testing, and behavioral health treatment. We conducted semi-structured interviews with 20 LMSM to elucidate their content, design, and implementation preferences for peer ambassador stories. Men were asked about story prompts, story contributor characteristics, story platform features, design preferences, and recommendations for enhancing the adoption and use of the peer ambassador technology platform among LMSM. Interviews were transcribed and analyzed via rapid qualitative analysis. Qualitative analyses identified 14 themes within 4 pre-specified domains. Collectively, the themes unified around the central concept that technology-delivered peer ambassador stories require a personalized, relational, culturally relevant touch to be acceptable and appropriate for LMSM. This study suggests that disseminating peer ambassador stories using electronic platforms and audio/video formats may enhance the reach of services and if they are personalized, relational, and culturally relevant. Findings have broad implications for informing other peer-based strategies to mitigate HIV disparities among LMSM.

Acceptability of 'Humpr': An Online Tool to Educate Adolescent Sexual Minority Males About Sexual Networking Applications.

We examined the acceptability of Humpr - an interactive, online tool developed to educate adolescent sexual minority males (ASMM) about how to safely navigate sexual networking applications (SNA). We developed Humpr as part of a larger HIV intervention trial in the U.S. In Humpr, 218 ASMM aged 14-20 (Mage = 17.18) created a mock dating profile, explored simulated user profiles, learned health-related information (e.g. slang indicating HIV/STI risks and/or drug use intentions), and then gave feedback regarding acceptability of the tool. Results showed that Humpr was very well-received, with 94% overall approval rates. Reasons for liking Humpr were evenly split between liking it for educational and entertaining reasons. Participants praised Humpr for its realistic design and interactive interface that allowed them to engage and connect with the tool. The majority (61%) had used SNAs in the past, but many still reported learning something new from Humpr. Participants also appreciated the acknowledgment of SNA use in ASMM and how the education was implemented in an open and judgment-free way. Topics learned from Humpr included how to be safe on SNAs and warning signs for HIV/STI risks. Suggested areas of improvement included having an opt-out option for those who do not wish to participate for any reason (e.g. discomfort) and additional educational content (e.g. consequences of being a minor on SNAs). Taken together, the findings offer preliminary evidence for the potential educational benefits of digital tools like Humpr for ASMM with and without prior SNA exposure.

SweetMama: Usability Assessment of a Novel Mobile Application Among Low-Income Pregnant People to Assist With Diabetes Management and Support.

Background: Mobile health tools may be effective strategies to improve engagement, education, and diabetes-related health during pregnancy. We developed SweetMama, a patient-centered, interactive mobile application (app) designed to support and educate low-income pregnant people with diabetes. Our objective was to evaluate the SweetMama user experience and acceptability. Methods: SweetMama is a mobile app with static and dynamic features. Static features include a customized homepage and resource library. Dynamic features include delivery of a theory-driven diabetes-specific curriculum via 1) motivational, tip, and goal-setting messages aligning with treatment and gestational age; 2) appointment reminders; and 3) ability to mark content as "favorite." In this usability assessment, low-income pregnant people with gestational or type 2 diabetes used SweetMama for 2 weeks. Participants provided qualitative feedback (via interviews) and quantitative feedback (via validated usability/satisfaction measures) on their experience. User analytic data detailed the duration and type of interactions users had with SweetMama. Results: Of 24 individuals enrolled, 23 used SweetMama and 22 completed exit interviews. Participants were mostly non-Hispanic Black (46%) or Hispanic (38%) individuals. Over the 14-day period, users accessed SweetMama frequently (median number of log-ins 8 [interquartile range 6-10]), for a median of 20.5 total minutes, and engaged all features. A majority (66.7%) rated SweetMama as having moderate or high usability. Participants emphasized design and technical strengths and beneficial effects on diabetes self-management and also identified limitations of the user experience. Conclusion: Pregnant people with diabetes found SweetMama to be user-friendly, informative, and engaging. Future work must study its feasibility for use throughout pregnancy and its efficacy to improve perinatal outcomes.

Keep It Up! 3.0: Study protocol for a type III hybrid implementation-effectiveness cluster-randomized trial.

BACKGROUND: Despite evidence that eHealth approaches can be effective in reducing HIV risk, their implementation requirements for public health scale up are not well established, and effective strategies to bring these programs into practice are still unknown. Keep It Up! (KIU!) is an online program proven to reduce HIV risk among young men who have sex with men (YMSM) and ideal candidate to develop and evaluate novel strategies for implementing eHealth HIV prevention programs. KIU! 3.0 is a Type III Hybrid Effectiveness-Implementation cluster randomized trial designed to 1) compare two strategies for implementing KIU!: community-based organizations (CBO) versus centralized direct-to-consumer (DTC) recruitment; 2) examine the effect of strategies and determinants on variability in implementation success; and 3) develop materials for sustainment of KIU! after the trial concludes. In this article, we describe the approaches used to achieve these aims. METHODS: Using county-level population estimates of YMSM, 66 counties were selected and randomized 2:1 to the CBO and DTC approaches. The RE-AIM model was used to drive outcome measurements, which were collected from CBO staff, YMSM, and technology providers. Mixed-methods research mapped onto the domains of the Consolidated Framework for Implementation Research will examine determinants and their relationship with implementation outcomes. DISCUSSION: In comparing our implementation recruitment models, we are examining two strategies which have shown effectiveness in delivering health technology interventions in the past, yet little is known about their comparative advantages and disadvantages in implementation. The results of the trial will further the understanding of eHealth prevention intervention implementation.

Effectiveness of the SMART Sex Ed program among 13-18 year old English and Spanish speaking adolescent men who have sex with men.

Adolescent men who have sex with men (AMSM) have a high HIV incidence and low utilization of testing and prevention services. However, very few HIV prevention programs exist that focus on the unique sexual health needs of AMSM. SMART is a stepped care package of eHealth interventions that comprehensively address the sexual and HIV prevention needs of AMSM. This study examines the impact of the first step of SMART, "SMART Sex Ed," on 13- to 18-year-old AMSM (n = 983) from baseline to three-month follow-up across 18 separate outcomes measuring HIV prevention attitudes, skills, and behaviors. We observed significant change from baseline to three-month post-intervention in nine HIV-related outcomes (e.g., receipt of HIV and STI test, HIV knowledge), as well as largely consistent effects across demographic subgroups (e.g., race, age, rural, low SES). Analyses observed no effects on condom use behaviors. SMART Sex Ed shows promise as an effective sexual health education program for diverse AMSM.

RESUMEN: Los adolescentes hombres que tienen sexo con otros hombres (AHSH) experimentan alta incidencia del VIH y baja utilización de servicios de prueba y prevención. Sin embargo, existen muy pocos programas de prevención del VIH enfocados en las necesidades particulares para la salud sexual de AHSH. SMART es un paquete de intervenciones de cuidado escalonado que usa plataformas electrónicas (eHealth) y que atiende de forma integrada las necesidades de salud sexual y prevención del VIH de AHSH. Este estudio examina el impacto de la primera etapa de SMART, llamada "SMART Sex Ed", entre AHSH (n = 983) entre las edades de 13 a 18 años e integra datos desde el reclutamiento con seguimiento cada 3 meses. Se recopilaron datos de 18 indicadores de actitudes, destrezas y prácticas de prevención del VIH (Ej. Historial de pruebas de VIH o ITS; conocimiento sobre VIH), así como los efectos en diferentes grupos demográficos (Ej. Raza, edad, área rural, y bajo nivel socioeconómico). Los análisis realizados demuestran que las características demográficas no tienen efecto en las prácticas de uso de condón. SMART Sex Ed es una intervención prometedora para educación sexual efectiva para AHSH.

Effectiveness of using e-government platform "Absher" as a tool for noncommunicable diseases survey in Saudi Arabia 2019-2020: A cross-sectional study.

Background: E-government platforms provide an opportunity to use a novel data source for population health surveillance (also known as e-health). Absher is a Saudi e-government platform with 23 million authenticated users, including residents and citizens in Saudi Arabia. All Absher users were invited to participate in a web-based survey to estimate the prevalence of noncommunicable diseases and their risk factors in Saudi Arabia. Objective: To assess the potential of using an e-government platform (Absher) to administer web-based health surveys. Methods: A cross-sectional, web-based health survey was administered to Absher users between April 2019 and March 2020. The survey instrument included eight items and took <5 min to complete. The respondents' data were compared to Saudi Arabia's 2016 census. Descriptive summary statistics of the prevalence of major noncommuncable diseases are presented and compared to population-based prevalence data from Saudi Arabia's World Health Survey (WHS) 2019. All analysis was conducted using Stata 13.0. Results: Overall, the Absher health survey had a 24.6% response rate, with most respondents being male (84%), Saudi (67%), and between 30 and 44 years of age (49%). Overall, the prevalence of noncommunicable diseases and risk factors among respondents was high for overweight (35%) and obesity (30%) and low for asthma (6%). The prevalence of diabetes, dyslipidemia, and hypertension was between 15 and 17% on average, and 26.5% were smokers. In comparison to population-based World Health Survey estimates, the Absher survey overestimated obesity, diabetes, dyslipidemia, hypertension, and smoking rates, and underestimated overweight, whereas asthma prevalence was similar for Absher and the WHS. Conclusions: With improvements in the study design, the use of e-government platforms can provide a useful and potentially low-cost data source for public health research.

COVID-19 symptom severity predicts neutralizing antibody activity in a community-based serological study.

Serological testing for SARS-CoV-2 IgG antibodies is used to assess their presence in blood samples from exposed individuals and provides a measure of the magnitude of immune response to infection. The measurement of neutralizing antibodies (NAbs) in particular provides information about the severity of prior infection and level of protective immunity against re-infection. Much of the work investigating the association between prior infection severity and NAb levels has been conducted among clinical populations, and less is known about this relationship in the general population. Accordingly, we utilize data from a large (n = 790) community-based cohort of unvaccinated, seropositive participants. We analyzed the association between NAb response, measured via surrogate virus neutralization assay, with patterns of symptoms and household exposure. Our results indicate no detectable NAb activity in 63.8% of the seropositive participants (n = 504). Those with detectable NAb levels demonstrated a positive relationship between NAb activity and both self-reported previous symptom severity and household exposure. These findings are significant in light of recent concerns about degree of protective immunity conferred by prior infection or vaccination, and we highlight the value of community-based research for investigating variation in immune response.

Low Levels of Neutralizing Antibodies After Natural Infection With Severe Acute Respiratory Syndrome Coronavirus 2 in a Community-Based Serological Study.

BACKGROUND: Confidence in natural immunity after infection with severe acute respiratory syndrome coronavirus 2 is one reason for vaccine hesitancy. METHODS: We measured antibody-mediated neutralization of spike protein-ACE2 receptor binding in a large community-based sample of seropositive individuals who differed in severity of infection (N = 790). RESULTS: A total of 39.8% of infections were asymptomatic, 46.5% were symptomatic with no clinical care, 13.8% were symptomatic with clinical care, and 3.7% required hospitalization. Moderate/high neutralizing activity was present after 41.3% of clinically managed infections, in comparison with 7.9% of symptomatic and 1.9% of asymptomatic infections. CONCLUSIONS: Prior coronavirus disease 2019 infection does not guarantee a high level of antibody-mediated protection against reinfection in the general population.

Use of a custom testing center locator tool to improve STI and HIV testing rates in adolescent men who have sex with men as part of an online sexual health program.

Adolescent men who have sex with men (AMSM) experience high rates of HIV diagnoses and low utilization of HIV testing and prevention services. Meta-analyses and literature reviews have reported significant effects of online programs at reducing HIV and STI risk and improving use of protective behaviors. SMART is a stepped care package of eHealth interventions that comprehensively address the sexual health and HIV prevention needs of diverse 13-18 year old AMSM nationwide. As part of the online curriculum, educational tools were created to promote specific learning objectives, including the importance of STI and HIV testing. This study describes the use of an HIV and STI testing center locator custom designed for the SMART intervention to promote STI and HIV testing in AMSM. Data were collected between April 2018 and July 2020 as part of the SMART trial assessing the impact of the first intervention of the SMART program, titled SMART Sex Ed, on 13-18 year old AMSM. Measures included AMSM interaction data with the locator tool, history of HIV and STI testing, and confidence to get tested at baseline and 3 months post intervention. Upon entering the SMART program, most participants (69.3%) had never received an HIV or STI test in their lifetime. From those who were enrolled in SMART Sex Ed (n=1075), 82.6% used the custom developed HIV and STI testing center locator tool and those who used the tool were significantly more confident to receive an HIV test and STI test (p < 0.01). Qualitative feedback from SMART participants described the tool as interactive, useful, and easy to use. Preliminary data analysis suggests that our custom developed HIV and STI testing center locator is an acceptable and useful tool with potential for implementation outside the SMART Program. Future analysis should examine if the testing center locator is an acceptable and effective tool outside of the SMART intervention package. Given these results, providing AMSMs easy to use and acceptable online tools with comprehensive, culturally relevant didactic content can significantly improve AMSM's utilization of HIV testing and prevention services.

Optimizing Engagement in an mHealth Intervention for Diabetes Support During Pregnancy: the Role of Baseline Patient Health and Behavioral Characteristics.

BACKGROUND: Mobile health (mHealth) technology that addresses diabetes mellitus in pregnancy has the potential to improve maternal and child health while diminishing socioeconomic and racial disparities. Little is known about health literacy, electronic health literacy, or patient characteristics that contribute to increased mHealth use. In this pilot study, we aimed to examine patient factors associated with user engagement with a novel app for diabetes support during pregnancy. METHOD: Low-income pregnant individuals with gestational or type 2 diabetes mellitus were recruited for a 2-week usability assessment of a novel mHealth smartphone application, "SweetMama," designed to improve diabetes care. This analysis of user characteristics was a pilot assessment of data from the usability study phase. Participants completed assessments of patient health literacy, electronic health literacy, diabetes self-efficacy, and activation. User metrics (eg, sessions and total duration of use) were evaluated by participant characteristics. Descriptive analyses were conducted to assess outcomes with respect to patient's clinical history, health literacy, electronic health literacy, diabetes self-efficacy, and activation. RESULTS: Twenty-two diverse, low-income pregnant patients with either gestational or type 2 diabetes engaged with SweetMama for 14 days. Participants with gestational diabetes had greater mean minutes of use per session and mean total duration of use than those with type 2 diabetes. Participants with greater electronic health literacy, lower patient activation, and greater self-efficacy demonstrated greater total duration of use. No user metrics differed significantly by participant general health literacy. CONCLUSIONS: Findings of this pilot study suggest engagement with a novel mHealth app for diabetes support during pregnancy varied by baseline behavioral and clinical characteristics. Results could indicate that digital health literacy better differentiates engagement patterns than general health literacy.

Geographic disparities in COVID-19 case rates are not reflected in seropositivity rates using a neighborhood survey in Chicago.

To date, COVID-19 case rates are disproportionately higher in Black and Latinx communities across the US, leading to more hospitalizations, and deaths in those communities. These differences in case rates are evident in comparisons of Chicago neighborhoods with differing race and/or ethnicities of their residents. Disparities could be due to neighborhoods with more adverse health outcomes associated with poverty and other social determinants of health experiencing higher prevalence of SARS-CoV-2 infection or due to greater morbidity and mortality resulting from equivalent SARS-CoV-2 infection prevalence. We surveyed five pairs of adjacent ZIP codes in Chicago with disparate COVID-19 case rates for highly specific and quantitative serologic evidence of any prior infection by SARS-CoV-2 to compare with their disparate COVID-19 case rates. Dried blood spot samples were self-collected at home by internet-recruited participants in summer 2020, shortly after Chicago's first wave of the COVID-19 pandemic. Pairs of neighboring ZIP codes with very different COVID-19 case rates had similar seropositivity rates for anti-SARS-CoV-2 receptor binding domain IgG antibodies. Overall, these findings of comparable exposure to SARS-CoV-2 across neighborhoods with very disparate COVID-19 case rates are consistent with social determinants of health, and the co-morbidities related to them, driving differences in COVID-19 rates across neighborhoods.

mRNA intramuscular vaccination produces a robust IgG antibody response in advanced neuromuscular disease.

SARS-CoV-2 vaccines protect against symptomatic and severe COVID-19. The BNT162b2/Pfizer and mRNA-1273/Moderna vaccines represent new vaccine technology relying on administration of mRNA encoding SARS-CoV-2 viral spike protein encased in lipid nanoparticles. The vaccines are administered as two doses into muscle, which elicits a strong response, typically within 14 days after the second dose. Neuromuscular diseases are characterized by the progressive loss of muscle and are often treated with chronic glucocorticoid steroids, both of which may contribute to a blunted immune response to vaccination. Here, we measured IgG antibody content and neutralizing antibody response after mRNA COVID-19 vaccination in non-ambulatory neuromuscular disease patients. After two doses of mRNA COVID-19 vaccine, median anti-receptor binding domain IgG and percent surrogate viral neutralization in non-ambulatory neuromuscular disease samples were significantly elevated similar to healthy vaccinated controls. As in healthy controls, COVID-19 vaccines produce greater antibody levels compared to those with a history of outpatient COVID-19 infection. This data documents that non-ambulatory neuromuscular disease patients respond well to two doses of mRNA COVID-19 vaccine despite low muscle mass and even chronic steroid use.

Projecting health labor market dynamics for a health system in transition: planning for a resilient health workforce in Saudi Arabia.

BACKGROUND: Health workforce planning is critical for health systems to safeguard the ability to afford, train, recruit, and retain the appropriate number and mix of health workers. This balance is especially important when macroeconomic structures are also reforming. The Kingdom of Saudi Arabia is moving toward greater diversification, privatization, and resiliency; health sectorreform is a key pillar of this transition. METHODS: We used the Ministry of Health Yearbook data on the number of workers and health expenditures from 2007 to 2018 and projected health labor market supply and demand of workers through 2030, evaluated the potential shortages and surpluses, and simulated different policy scenarios to identify relevant interventions. We further focused on projections for health workers who are Saudi nationals and health worker demand within the public sector (versus the private sector) to inform national objectives of reducing dependency on foreign workers and better deploying public sector resources. RESULTS: We projected the overall health labor market to demand 9.07 physicians and nurses per 1,000 population (356,514) in 2030; the public sector will account for approximately 67% of this overall demand. Compared to a projected supply of 10.16 physicians and nurses per 1,000 population (399,354), we estimated an overall modest surplus of about 42,840 physicians and nurses in 2030. However, only about 17% of these workers are estimated to be Saudi nationals, for whom there will be a demand shortage of 287,895 workers. Among policy scenarios considered, increasing work hours had the largest effect on reducing shortages of Saudi workers, followed by bridge programs for training more nurses. Government resources can also be redirected to supporting more Saudi nurses while still ensuring adequate numbers of physicians to meet service delivery goals in 2030. CONCLUSION: Despite projected overall balance in the labor market for health workers in 2030, without policy interventions, severe gaps in the Saudi workforce will persist and limit progress toward health system resiliency in Saudi Arabia. Both supply- and demand-side policy interventions should be considered, prioritizing those that increase productivity among Saudi health workers, enhance training for nurses, and strategically redeploy financial resources toward employing these workers.

Effective COVID-19 Control: A Comparative Analysis of the Stringency and Timeliness of Government Responses in Asia.

AIM: Many governments in East and Southeast Asia responded promptly and effectively at the onset of the COVID-19 pandemic. Synthesizing and analyzing these responses is vital for disease control evidence-based policymaking. METHODS: An extensive review of COVID-19 control measures was conducted in selected Asian countries and subregions, including Mainland China, Hong Kong, Taiwan, South Korea, Singapore, Japan, and Vietnam from 1 January to 30 May 2020. Control measures were categorized into administrative, public health, and health system measures. To evaluate the stringency and timeliness of responses, we developed two indices: the Initial Response Index (IRI) and the Modified Stringency Index (MSI), which builds on the Oxford COVID-19 Government Response Tracker (OxCGRT). RESULTS: Comprehensive administrative, public health, and health system control measures were implemented at the onset of the outbreak. Despite variations in package components, the stringency of control measures across the study sites increased with the acceleration of the outbreak, with public health control measures implemented the most stringently. Variations in daily average MSI scores are observed, with Mainland China scoring the highest (74.2), followed by Singapore (67.4), Vietnam (66.8), Hong Kong (66.2), South Korea (62.3), Taiwan (52.1), and Japan (50.3). Variations in IRI scores depicting timeliness were higher: Hong Kong, Taiwan, Vietnam, and Singapore acted faster (IRI > 50.0), while Japan (42.4) and Mainland China (4.2) followed. CONCLUSIONS: Timely setting of stringency of the control measures, especially public health measures, at dynamically high levels is key to optimally controlling outbreaks.

Comparison of IgG and neutralizing antibody responses after one or two doses of COVID-19 mRNA vaccine in previously infected and uninfected individuals.

BACKGROUND: Recent reports have suggested that among individuals previously infected with SARS-CoV-2, a single mRNA vaccine dose is sufficient to elicit high levels of immunity. METHODS: We compared anti-SARS-CoV-2 spike receptor binding domain (RBD) IgG antibody concentrations and antibody-mediated neutralization of spike-angiotensin-converting enzyme (ACE2) receptor binding in vitro following vaccination of non-hospitalized participants by sero-status and acute virus diagnosis history. Participants were analysed before and after mRNA vaccination (BNT162b2/Pfizer or mRNA-1273/Moderna) in a community-based, home-collected, longitudinal serosurvey in the Chicago area (USA); none reported hospitalization for COVID-19. Samples were collected in January and February 2021. Before vaccination, some reported prior positive acute viral diagnostic testing and were seropositive (COVID-19+); the others who did not report acute viral diagnostic testing were categorized as seropositive or seronegative based on anti-spike RBD IgG test results. FINDINGS: Of 307 unique vaccine recipients, 46 reported a prior COVID-19 diagnosis and were seropositive (COVID-19 +). Of the 261 with no history of acute viral diagnostic testing, 117 were seropositive and 144 seronegative before vaccination. The median age was 38 years (range 21-83) with 67 female and 33% male; 40% were non-White. Responses were evaluated after one (n = 142) or two (n = 191) doses of BNT162b2 or mRNA-1273 vaccine. After one dose, median post-vaccine IgG concentration and percent surrogate neutralization were each significantly higher among the COVID-19+ (median 48·2 µg/ml, IgG; > 99.9% neutralization) compared to the seropositives (3·6 µg /ml IgG; 56.5% neutralization) and seronegatives (2·6 µg /ml IgG; 38·3% neutralization). The latter two groups reached > 95% neutralization after the second vaccine dose. INTERPRETATION: After one dose of mRNA vaccine, individuals previously diagnosed with COVID-19 responded with high levels of anti-RBD IgG and surrogate neutralization of spike-ACE2 interaction. One dose of mRNA vaccine was not sufficient to generate comparably high responses among most persons previously infected with SARS-CoV-2 without a clinical COVID-19 diagnosis, nor among seronegative persons. FUNDING: National Science Foundation 2035114, NIH 3UL1TR001422-06S4, and Northwestern University Office of Research.

Cohabitation With a Known Coronavirus Disease 2019 Case Is Associated With Greater Antibody Concentration and Symptom Severity in a Community-Based Sample of Seropositive Adults.

In a community-based sample of seropositive adults (n = 1101), we found that seropositive individuals who lived with a known coronavirus disease 2019 (COVID-19) case exhibited higher blood anti-severe acute respiratory syndrome coronavirus 2 spike receptor-binding domain immunoglobulin G concentrations and greater symptom severity compared to seropositive individuals who did not live with a known COVID-19 case.