Search Results for: Identificate le origini evolutive di SARS-CoV-2

Background
Infectious agents such as SARS-CoV-2 require strategies to contain outbreaks, particularly in hospitals where the spread of infection is most likely. Biometric monitoring of heart rate, temperature, oxygen saturations and sleep might provide important early warning signs for SARS-CoV-2. This study aimed to determine whether a smart medical device (E4 wristband) and a pulse oximeter used to continuously measure heart rate, skin temperature and oxygen saturation would predict the onset of SARS-CoV-2 infection.

Methods
A single-centre, prospective observational cohort of 30 healthcare workers (HCWs) working in areas at high risk for exposure to SARS-CoV-2 were enrolled. HCWs were tested for SARS-CoV-2 using RT-qPCR of daily self-administered swabs for 30 days. Each participant was asked to wear an E4 wristband to measure changes in their heart rate, skin temperature and sleep throughout the study.

Results
Nine (30%) HCWs (median (range) age of 39 (27–57) years) tested positive for COVID-19. No significant differences were found in the pre-infection and post-infection variations in the heart rate (p=0.31) or skin temperature (p=0.44). Seven of the nine positive subjects reported symptoms at some point during the study period: unusual fatigue (40%), headache (33%) and runny nose (22%) were the most frequent. Analysis of daily trends in observations demonstrated significant fluctuations in biometric parameters.

Conclusion
These results suggest that wearable technology might be useful in documenting signs of SARS-CoV-2 infection in exposed HCWs.

Trial registration number
NCT04363489.

Introduction
During the pandemic, overweight and obese adolescents were at a higher risk of COVID-19 infection. Indonesia’s government has implemented prevention programmes and immunisation; however, the rise in SARS-CoV-2 infections among adolescents is exacerbated by low-quality diet and lifestyle habits. Also, the vaccine programme is not prioritised in this population. To address this, a solution involves providing probiotics and counselling on healthy lifestyle habits to improve diet and immunity. Therefore, we designed a protocol for a randomised controlled trial with a 20-week intervention to investigate the effect of probiotics supplementation and counselling on healthy lifestyle habits, including healthy eating and physical activity, and psychosocial stimulation, on nutritional status and antibody response against SARS-CoV-2 in this group.

Methods and analysis
This clinical trial aims to investigate the effects of probiotic supplementation on healthy overweight and obese adolescents. The study will involve 440 adolescents aged 12–17 living in Jakarta, Surabaya or Yogyakarta for at least 6 months and have completed at least two doses of the COVID-19 vaccine. The intervention group will receive daily probiotic supplementation of three strains, including Bifidobacterium animalis subsp. Lactis (BB-12), Lactobacillus acidophilus (LA-5) and Lactobacillus rhamnosus (LGG), at the level of 109–1010 colony-forming units for 20 weeks, while the control group will receive a placebo. Both groups will receive weekly counselling on healthy eating habits, physical activity and psychosocial stimulation. The primary outcomes will be changes in the body mass index for age z-score and IgG specific to SARS-CoV-2 titre concentrations between groups. The secondary outcomes will include changes in secretory IgA specific to SARS-CoV-2 titre concentrations, monoclonal antibodies against SARS-CoV-2 spike protein, gut microbiota diversity and the score of Healthy Eating Index 2015.

Ethics and dissemination
The study protocol was approved by the Ethics Committee of the Faculty of Medicine, Universitas Indonesia-Cipto Mangunkusumo Hospital (KET 763/UN2.F1/ETIK/PPM.00.02/2022: 1 August 2022). The study results will be disseminated in open-access international journals, scientific meetings and conferences with stakeholders.

Trial registration number
The study has been registered at https://clinicaltrials.gov with identifier number NCT05623007.

Objectives
To assess the prevalence of SARS-CoV-2 antibodies in the residents of Kibera informal settlement in Nairobi, Kenya, before vaccination became widespread, and explore demographic and health-related risk factors for infection.

Design
A cross-sectional study.

Setting
Kibera informal settlement, Nairobi, Kenya.

Participants
Residents of Kibera informal settlement between October 2019 and August 2021, age 1 year and above who reported no current symptoms of COVID-19.

Main outcome measures
Associations were determined between SARS-CoV-2 positive tests measured with one rapid test and two ELISAs and demographic and health-related factors, using Pearson’s 2 test. Crude OR and adjusted OR were calculated to quantify the strength of associations between variables and seropositive status.

Results
A total of 438 participants were recruited. Most (79.2%) were age 18–50 years; females (64.2%) exceeded males. More than one-third (39.1%) were unemployed; only 7.4% were in formal, full-time employment. Less than one-quarter (22.1%) self-reported any underlying health conditions. Nearly two-thirds (64.2%) reported symptoms compatible with COVID-19 in the previous 16 months; only one (0.23%) had been hospitalised with a reported negative COVID-19 test. 370 (84.5%) participants tested positive in any of the three tests. There was no significant difference in SARS-CoV-2 seropositivity across age, sex, presence of underlying health conditions, on medication or those ever tested for SARS-CoV-2. Multiple logistic regression analysis showed that COVID-19 symptoms in the previous 16 months were the only significant independent predictor of seropositivity (p=0.0085).

Conclusion
High SARS-CoV-2 exposure with limited morbidity was found in the residents of Kibera informal settlement. The study confirms other reports of high SARS-CoV-2 exposure with limited morbidity in slum communities. Reasons cited include the high infectious disease burden on the African continent, demographic age structure and underreporting due to limited testing and lack of access to healthcare services; genetic factors may also play a role. These factors require further investigation.

Stroke, Ahead of Print. BACKGROUND:The VIPS (Vascular Effects of Infection in Pediatric Stroke) II prospective cohort study aimed to better understand published findings that common acute infections, particularly respiratory viruses, can trigger childhood arterial ischemic stroke (AIS). The COVID-19 pandemic developed midway through enrollment, creating an opportunity to assess its impact.METHODS:Twenty-two sites (North America, Australia) prospectively enrolled 205 children (aged 28 days to 18 years) with AIS from December 2016 to January 2022, including 100 cases during the COVID-19 pandemic epoch, defined here as January 2020 to January 2022. To assess background rates of subclinical infection, we enrolled 100 stroke-free well children, including 39 during the pandemic. We measured serum SARS-CoV-2 nucleocapsid total antibodies (present after infection, not vaccination; half-life of 3–6 months). We assessed clinical infection via parental interview.RESULTS:The monthly rate of eligible AIS cases declined from spring through fall 2020, recovering in early 2021 and peaking in the spring. The prepandemic and pandemic cases were similar except pandemic cases had fewer clinical infections in the prior month (17% versus 30%;P=0.02) and more focal cerebral arteriopathy (20% versus 11%;P=0.09). Among pandemic cases, 26 of 100 (26%) had positive antibodies, versus 4 of 39 (10%) of pandemic-era well children (P=0.04). The first SARS-CoV-2 positive case occurred in July 2020. Ten of the 26 (38%) positive cases had a recent infection by parental report, and 7 of those 10 had received a diagnosis of COVID-19. Only 1 had multisystem inflammatory syndrome in children. Median (interquartile range) nucleocapsid IgG total levels were 50.1 S/CO (specimen to calibrator absorbance ratio; 26.9–95.3) in the positive cases and 18.8 (12.0–101) in the positive well children (P=0.33).CONCLUSIONS:The COVID-19 pandemic may have had dual effects on childhood AIS: an indirect protective effect related to public health measures reducing infectious exposure in general, and a deleterious effect as COVID-19 emerged as another respiratory virus that can trigger childhood AIS.

Objectives
SARS-CoV-2 poses significant challenges to people living with diabetes (PLWD). This systematic review aimed to explore the impact of COVID-19 on mortality, complications associated with diabetes and haematological parameters among PLWD.

Design
Systematic review and meta-analysis using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

Data sources
EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials and LILACS were searched between 1 December 2019 and 14 January 2025.

Eligibility criteria for selecting studies
Eligible studies included case-control and cohort studies involving PLWD categorised into two groups: those with confirmed SARS-CoV-2 infection and those without.

Data extraction and synthesis
Meta-analyses estimated the odds ratios (ORs) and mean differences (MDs) of outcomes including mortality, intensive care unit (ICU) admission, diabetic ketoacidosis (DKA), acute kidney injury, hospitalisation length and haematological parameters. We pooled results using random-effects models and assessed study quality with the Newcastle-Ottawa Scale. A funnel plot was used to detect potential publication bias. The overall certainty of evidence was assessed using GRADE.

Results
25 of 7266 unique studies were eligible, including 1 154674 PLWD (561 558 with COVID-19 and 593 116 without COVID-19). SARS-CoV-2 infection in PLWD was associated with significantly increased mortality (OR 2.52, 95% CI 1.45 to 4.36, I2=99%), acute kidney injury (3.69, 95% CI 2.75 to 4.94, I2=0%), random plasma glucose in subjects with type 1 diabetes (MD 20.38 mg/dL, 95% CI 7.39 to 33.36, I2=0%), haemoglobin A1C in subjects with type 2 diabetes (0.21%, 95% CI 0.05 to 0.38, I2=13%), creatinine (0.12 mg/dL, 95% CI 0.04 to 0.19, I2=0%), C reactive protein (38.30 mg/L, 95% CI 4.79 to 71.82, I2=82%) and D-dimer (1.52 µg/mL, 95% CI 0.73 to 2.31, I2=0%). No significant differences were observed in the incidence of ICU admission and DKA, hospitalisation length, haemoglobin, leucocyte, lymphocyte, neutrophil to lymphocyte ratio, platelet, blood urea nitrogen, estimated glomerular filtration rate, procalcitonin, albumin, ferritin and bilirubin among PLWD with and without SARS-CoV-2 infection.

Conclusions
SARS-CoV-2 infection is associated with elevated risks of mortality and acute kidney injury and poor glycaemic control in PLWD, alongside increased levels of inflammatory and coagulation biomarkers. These findings underscore the urgent need for tailored clinical management strategies for PLWD with COVID-19.

PROSPERO registration number
CRD42023418039.

Objectives
SARS-CoV-2 poses significant challenges to people living with diabetes (PLWD). This systematic review aimed to explore the impact of COVID-19 on mortality, complications associated with diabetes and haematological parameters among PLWD.

Design
Systematic review and meta-analysis using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

Data sources
EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials and LILACS were searched between 1 December 2019 and 14 January 2025.

Eligibility criteria for selecting studies
Eligible studies included case-control and cohort studies involving PLWD categorised into two groups: those with confirmed SARS-CoV-2 infection and those without.

Data extraction and synthesis
Meta-analyses estimated the odds ratios (ORs) and mean differences (MDs) of outcomes including mortality, intensive care unit (ICU) admission, diabetic ketoacidosis (DKA), acute kidney injury, hospitalisation length and haematological parameters. We pooled results using random-effects models and assessed study quality with the Newcastle-Ottawa Scale. A funnel plot was used to detect potential publication bias. The overall certainty of evidence was assessed using GRADE.

Results
25 of 7266 unique studies were eligible, including 1 154674 PLWD (561 558 with COVID-19 and 593 116 without COVID-19). SARS-CoV-2 infection in PLWD was associated with significantly increased mortality (OR 2.52, 95% CI 1.45 to 4.36, I2=99%), acute kidney injury (3.69, 95% CI 2.75 to 4.94, I2=0%), random plasma glucose in subjects with type 1 diabetes (MD 20.38 mg/dL, 95% CI 7.39 to 33.36, I2=0%), haemoglobin A1C in subjects with type 2 diabetes (0.21%, 95% CI 0.05 to 0.38, I2=13%), creatinine (0.12 mg/dL, 95% CI 0.04 to 0.19, I2=0%), C reactive protein (38.30 mg/L, 95% CI 4.79 to 71.82, I2=82%) and D-dimer (1.52 µg/mL, 95% CI 0.73 to 2.31, I2=0%). No significant differences were observed in the incidence of ICU admission and DKA, hospitalisation length, haemoglobin, leucocyte, lymphocyte, neutrophil to lymphocyte ratio, platelet, blood urea nitrogen, estimated glomerular filtration rate, procalcitonin, albumin, ferritin and bilirubin among PLWD with and without SARS-CoV-2 infection.

Conclusions
SARS-CoV-2 infection is associated with elevated risks of mortality and acute kidney injury and poor glycaemic control in PLWD, alongside increased levels of inflammatory and coagulation biomarkers. These findings underscore the urgent need for tailored clinical management strategies for PLWD with COVID-19.

PROSPERO registration number
CRD42023418039.

Isolò la Sars nel 2003. Lezione su accesso a cure e prevenzione

Stroke, Ahead of Print. BACKGROUND:The modified Rankin Scale (mRS) is a key measure of functional outcomes in stroke trials. To minimize variability, structured tools like the Rankin Focused Assessment and central adjudication are recommended. This study compares local versus centrally adjudicated mRS scores in the MOST trial (Multi-Arm Optimization of Stroke Thrombolysis).METHODS:MOST was a phase 3, single-blind, randomized trial evaluating argatroban, eptifibatide, or placebo in addition to intravenous thrombolysis. The primary outcome, 90-day mRS score, was gathered through in-person video recordings by blinded local personnel. Recordings were sent to central adjudicators for final scoring. As in-person visits became limited due to SARS-CoV-2, remote interviews were allowed. We hypothesized that local mRS scores would be moderately associated with central scores. Fleiss-Cohen quadratic weighted κ statistics were used to determine the strength of agreement.RESULTS:Out of 514 participants, 378 had recorded visits available (121 in-person video, 157 remote video, 100 remote audio). Local assessors were blinded 96.8% of the time and 85.4% of visits used the Rankin Focused Assessment. Overall agreement between local and central mRS scores was good (weighted κ, 0.87 [95% CI, 0.83–0.90]). A nonsignificant decrease in strength of agreement was noted for those with a nonzero baseline mRS (mRS score=0, 0.87 [95% CI, 0.84–0.91] versus mRS score >0, 0.80 [95% CI, 0.68–0.91]). Trial conclusions were unchanged when utilizing the local mRS versus central adjudication.CONCLUSIONS:Local mRS scores demonstrated strong agreement with central scores across all assessment modes. With blinded end point assessments, central mRS adjudication in acute stroke trials may not be necessary.REGISTRATION:URL:https://www.clinicaltrials.gov; Unique identifier: NCT03735979.

Objectives
To examine the effectiveness of exercise interventions to improve long COVID symptoms and the tolerance of exercise interventions among people with long COVID.

Design
Systematic review.

Data sources
Medline via EBSCOhost, Embase via OVID and CENTRAL via the Cochrane Library up to 28 February 2023.

Eligibility criteria for selecting studies
Inclusion criteria were: (1) participants with long COVID, as defined by study authors; (2) random assignment to either an exercise intervention or a comparison group and (3) a quantitative measure of at least 1 of the 12 core long COVID outcomes. Exclusion criteria were: (1) signs or symptoms not reasonably attributable to prior SARS-CoV-2 infection; (2) pre-exposure or postexposure prophylaxis for COVID-19 or the prevention of long COVID symptoms and (3) interventions where the primary exercise component is breathing or respiratory muscle training.

Data extraction and synthesis
Two reviewers independently extracted data, and studies were narratively synthesised.

Results
Eight studies were included. Follow-up periods ranged from 2 to 28 weeks (mean=8.5 weeks). Sample sizes ranged from 39 to 119 (mean=56). All studies were in adults (mean age=49.9 years) and both sexes (mean female proportion=53.9%). Four studies were at low risk of bias, two were unclear and two were high. The evidence suggests that exercise interventions lead to short-term improvements in dyspnoea, fatigue, physical function and the physical domain of quality of life among people with long COVID. Of the five studies that reported adverse events, rates were low and, when reported, mild. Of the seven studies that reported sufficient relevant information, 1 of 252 participants who received exercise discontinued the intervention due to tolerance-related issues.

Conclusion
Available evidence suggests that exercise interventions may be beneficial and tolerable among some people with long COVID. However, the evidence base consists of a limited number of studies with small sample sizes and short follow-up periods.

Introduction
The elderly are particularly vulnerable to morbidity and mortality from COVID-19, the disease caused by the SARS-CoV-2. Approximately 20% of the elderly showed no antibodies 3–5 months post-second dose of the COVID-19 vaccine. As probiotics have been shown to increase influenza-specific antibody levels post-influenza vaccination, we aim to reduce the percentage of participants without antibodies against the SARS-CoV-2 spike protein receptor-binding domain (anti-S1-RBD) at 6 months post-vaccination.

Methods and analysis
Our study design is a double-blind randomised controlled trial, using intention-to-treat analysis. Eligible participants are a purposive sample of 688 adults aged 65–89 years, in Quebec, Canada, not diagnosed with COVID-19 in the 3 months prior to recruitment and who wish to receive a government-recommended mRNA booster (Pfizer-BioNTech, Moderna) vaccine. The intervention consists of one capsule/day of a probiotic dietary supplement of Lacticaseibacillus rhamnosus and Lacticaseibacillus casei 6×109 CFU/capsule or a placebo, for 15 days pre-booster and post-booster vaccine. All participants provide dried blood spot samples at three timepoints (inclusion, 3 and 6 months post-vaccination) and a stool sample for microbiome analysis. A subgroup of 100 participants living near Sherbrooke, Quebec, is expected to volunteer for two onsite blood-test visits (at inclusion and 6 months post-vaccination). The primary outcome is the percentage of participants without anti-S1-RBD antibodies at 6 months post-vaccination. Secondary outcomes include longitudinal analysis of anti-S1-RBD and anti-N antibodies at three timepoints. In the subgroup, serum levels of neutralising antibodies will be determined at inclusion and 6 months post-vaccination. Probiotic and vaccine side effects are monitored. At the end of the study, we expect to identify the adjuvant effect of probiotic on vaccine-induced immune response.

Ethics and dissemination
The study was approved by Research Ethics Board of the Centre Intégré Universitaire de Santé et des Services Sociaux de l’Estrie- Centre Hospitalier Universitaire de Sherbrooke (CIUSSS de l’Estrie-CHUS) and the CHU de Québec-Université Laval # MP-31-2022-4598 as well as Health Canada. All participants will provide informed consent. Results will be disseminated to the scientific community and to all networks related in this research.

Trial registration number
NCT05195151.

Introduction
SARS-CoV-2 disease (COVID-19) has had an enormous health and economic impact globally. Although primarily a respiratory illness, multi-organ involvement is common in COVID-19, with evidence of vascular-mediated damage in the heart, liver, kidneys and brain in a substantial proportion of patients following moderate-to-severe infection. The pathophysiology and long-term clinical implications of multi-organ injury remain to be fully elucidated. Age, gender, ethnicity, frailty and deprivation are key determinants of infection severity, and both morbidity and mortality appear higher in patients with underlying comorbidities such as ischaemic heart disease, hypertension and diabetes. Our aim is to gain mechanistic insights into the pathophysiology of multiorgan dysfunction in people with COVID-19 and maximise the impact of national COVID-19 studies with a comparison group of COVID-negative controls.

Methods and analysis
COmorbidities and Sociodemographic factors on Multiorgan Injury following COVID-19 (COSMIC) is a prospective, multicentre UK study which will recruit 200 subjects without clinical evidence of prior COVID-19 and perform extensive phenotyping with multiorgan imaging, biobank serum storage, functional assessment and patient reported outcome measures, providing a robust control population to facilitate current work and serve as an invaluable bioresource for future observational studies.

Ethics and dissemination
Approved by the National Research Ethics Service Committee East Midlands (REC reference 19/EM/0295). Results will be disseminated via peer-reviewed journals and scientific meetings.

Trial registration number
COSMIC is registered as an extension of C-MORE (Capturing Multi-ORgan Effects of COVID-19) on ClinicalTrials.gov (NCT04510025).

Background
Understanding the impact of COVID-19 on the unplanned patient flow within hospitals is crucial for future preparedness planning and response strategies. We examined the impact of COVID-19 on the unplanned patient flow in a Danish healthcare region, with particular focus on emergency departments (EDs).

Methods
A descriptive multicentre cohort study was conducted comparing unplanned patient contacts during the first year of the COVID-19 pandemic (1 March 2020–28 February 2021) with the previous year (1 March 2019–29 February 2020). The study examined changes in patient flow and key flow variables—number of contacts, length of stay (LOS), triage, re-contacts, mortality, International Classification of Diseases (ICD)-10 codes, isolations and SARS-CoV-2-positive patients—and compared differences between five EDs in the Central Denmark Region.

Results
The overall number of unplanned patient contacts decreased 3.6% from the previous period (257 657) to the COVID-19 period (248 706). The decrease was lowest in EDs compared with other departments and was primarily detected during lockdowns, which were followed by months of increased ED contacts.
Although overall patient contacts decreased, an increase in proportions was observed in contacts with a LOS

Objectives
To investigate the prevalence and factors of COVID-19 infection in children aged 0–6 years within Hunan Province following the deregulation of epidemic control.

Design
This is an observational study in epidemiology, using an on-site questionnaire survey to investigate the current status of COVID-19 infection and its influencing factors in children aged 0–6 years in Hunan Province from 16 February to 24 March 2023.

Setting
Multi-stage stratified sampling method was applied in this study. The regions were categorised as developed, medium and underdeveloped. One municipality was selected from each category. In each municipality, one district and one county were chosen for cluster sampling.

Participants
Children aged 0–6 years in Hunan Province.

Results
A total of 78 115 children aged 0–6 years were enrolled in this study, of 30 659 (39.2%) had a confirmed positive SARS-CoV-2 test result or related clinical symptoms. The majority of COVID-19 infections in children were of mild type (92.0%), and very few were severe and critical (0.4% and 0.1%). The majority (74.6%–88.7%) of children had minimal lifestyle behavioural changes after infected with COVID-19. Parents of the child working as a staff member (OR=0.654, 95% CI: 0.603, 0.709) and civil servant (OR=0.865, 95% CI: 0.794, 0.941), living in a rural area (OR=0.384, 95% CI: 0.369, 0.400) and no COVID-19 exposure (OR=0.108, 95% CI: 0.104, 0.113) were protective factors for COVID-19 infection in children.

Conclusion
Children experienced a large number of COVID-19 infections following the deregulation, fewer severe cases and fewer changes in lifestyle. Easing epidemic control measures in the later stage of the pandemic did not aggravate the consequences of the epidemic.

Objectives
To analyse the relationships between SARS-CoV-2 laboratory testing capacity (TC) and socioeconomic factors (wealth, governance and social inequality) across 109 countries in 2020–2021, to identify potential determinants of global disparities in TC during the COVID-19 pandemic.

Design
An ecological study using regression analyses to explore the associations between TC and socioeconomic determinants within and across global regions.

Setting/participants
Data from 109 countries from Our World in Data, the WHO, the United Nations and others grouped into six geographic and sociodemographic regions (global burden of disease regions), were analysed separately for the years 2020–2021 based on differential vaccine availability and country-level responses throughout the pandemic.

Outcome measures
Relationships between SARS-CoV-2 TC and factors such as vaccination rates, wealth, vulnerable employment (VE), gender and income inequality within and across world regions in 2020–2021.

Results
TC increased a minimum of 2.1-fold for ‘Sub-Sahara’ (median TC 1800–3700 tests) to a maximum of 4.9-fold for ‘Asia and Oceania’ (4500–22 000) between 2020 and 2021. Factors associated with TC among the socioeconomic variables included VE that was associated with reduced TC both in 2020 (relative change (RC) –43%; 95% CI –57% to –25%) and 2021 (RC –46%; 95% CI –62% to –24%) and employment-to-population ratio that had a positive effect on TC in 2021 (RC 27%; 95% CI 44% to 55%). Socioeconomic variables showed similar patterns for both the established measles–mumps–rubella and the new COVID-19 vaccines. Region-level analyses revealed stark heterogeneity in the associations between socioeconomic variables and TC between the analysed years (2020 vs 2021) and across regions. Region-specific trends showed that in Latin America and Asia/Oceania, TC was linked to health expenditure in both analysed years (RC2020: 199%; 95% CI 74% to 405%; RC2021: 142%; 95% CI 67% to 24%). VE was associated with decreased TC in the ‘high-income’, ‘Central Europe’ and ‘Sub-Saharan’ regions.

Conclusions
Socioeconomic and gender inequalities play a significant role in determining SARS-CoV-2 TC. These inequalities underscore the necessity of ensuring equitable access to health services and targeted public health interventions, particularly in resource-limited settings, to improve health outcomes and pandemic preparedness. Socioeconomic and gender disparities can exacerbate health inequalities and hinder the effectiveness of public health policies in a globally interconnected world.

To the Editor Myocarditis, pericarditis, and myopericarditis are inflammatory heart conditions recognized as adverse events linked to COVID-19 mRNA vaccines, but their population-level clinical outcomes remain underdocumented. In a recent JAMA article, Ms Semenzato and colleagues provided valuable insights by comparing different myocarditis etiologies; the exclusion of pericarditis is notable. Accurate identification of myocarditis is crucial for both diagnosis and management. Case definitions from the Centers for Disease Control and Prevention and the Brighton Collaboration offer structured criteria, especially for vaccine-related cases. In the study by Semenzato and colleagues, myocarditis occurring within 7 days of vaccination was classified as postvaccine myocarditis, while myocarditis occurring within 30 days of SARS-CoV-2 infection was labeled post–COVID-19 myocarditis. In contrast, the Brighton Collaboration’s definitions, widely used in Canada for evaluating myocarditis and pericarditis after vaccination, include graduated levels of diagnostic certainty (definite, probable, possible) and consider events occurring within 6 weeks of vaccination as likely vaccine-associated. The Centers for Disease Control and Prevention reports onset of myocarditis symptoms ranging from 0 to 40 days after vaccination. while data from the Vaccine Adverse Event Reporting System, one of the largest global systems for tracking vaccine-associated adverse events, suggest that onset of myocarditis and pericarditis can extend beyond 120 days after vaccination. The study’s 7-day window may underestimate vaccine-associated myocarditis.

Objectives
Despite widespread vaccination programmes and consensus recommendations, the understanding of the durability of COVID-19 vaccination against ensuing infection and transmission at the individual level is incomplete. The objective of this study was to estimate the effects of time-varying covariates including time since vaccination and symptoms on subsequent positive SARS-CoV-2 test results and assess the stability of these effects between March 2020 and April 2022.

Design
Prospective cohort study.

Setting
Urban university in the USA.

Participants
Drexel University students, faculty, and staff (n=15 527) undergoing mandatory COVID-19 symptom tracking, testing and vaccinations.

Intervention
Systematic symptom tracking and SARS-COV-2 testing starting in September 2020 and mandatory COVID-19 vaccination starting in September 2021.

Main outcomes and measures
COVID-19 vaccine effectiveness modified by time since vaccination and symptoms.

Results
Using fit-for-purpose digitally based symptom and vaccine tracking and mandatory comprehensive testing for SARS-CoV-2 infection, we estimate the time-dependent effects of vaccination, symptoms and covariates on the risk of infection with a Cox proportional hazards model based on calendar time scale. We found a strong protective effect of vaccination against symptomatic infection. However, there was strong evidence of a protective effect against infection only in the first 90 days after completed vaccination, and only against symptomatic versus asymptomatic infection. The overall estimated effect of vaccination within 30 days, including asymptomatic infections, was 37.3% (95% CI 26%, 47%). Vaccine effect modification by reported symptoms and time period was estimated, revealing the protective effect of vaccination within 90 days against symptomatic infection that varied from 90% (95% CI 84%, 94%) to 49%(95% CI –77%, 85%) across time periods.

Conclusions
This study is among the first to prospectively capture complete COVID-19 symptom, testing and vaccination data over a multiyear period. Overall effectiveness of the COVID-19 vaccine against subsequent infection, including transmissible asymptomatic infections, is modest and wanes after 90 days. Vaccination policies may need to take these issues into account.