SARS-CoV-2 breakthrough infections in a retrospective cohort of vaccinated university students and employees

Vaccination

Objectives: to determine factors associated with rates of SARS-CoV-2 infection and to determine whether anti-receptor-binding domain (RBD) IgG levels were associated with the rates of infectionDesign: prospective cohort of 34 months’ duration (February 2021 to December 2023)Setting: teachers and education workers working ≥8 hours per week in the Canadian province of OntarioParticipants: 3155 education workers were eligible for the risk factor analysis; 2977 for the serological analysisPrimary outcome measure: SARS-CoV-2 infection, symptomatic or asymptomaticResults: 1909 SARS-CoV-2 infections were reported (0.93 per 1000 participant-days); the highest incidence occurred during the period dominated by the Omicron BA.2 variant (2.01/1000 participant-days). After a median of 740 (interquartile range 361, 971) days of follow-up, participants who received three (adjusted hazard ratio (aHR) 0.24; 95% CI 0.11, 0.50; p<0.001), four (aHR 0.14; 95% CI 0.07, 0.30; p<0.001), or five or more (aHR 0.14; 95% CI 0.06, 0.30; p<0.001) doses of COVID-19 vaccines had lower rates of infection than participants who received <2 doses. Likewise, those who had immunity from a previous infection had lower rates of infection (aHR 0.05; 95% CI 0.04, 0.07) than those without. Participants 30 years of age or older had a lower rate of infection than participants 20-29 years old and those with Caucasian/European ancestry had a lower rate of infection (aHR 0.83; 95% CI 0.71, 0.96; p=0.01) than others. Also, compared to participants without known contact with an infected person, those in close contact with an infected household member (aHR 1.54; 95% CI 1.39, 1.71; p<0.001), coworker or student (aHR 1.22; 95% CI 1.04, 1.42, p=0.012), or individuals from more than one setting (aHR 1.45; 95% CI 1.29, 1.63; p<0.001) had higher rates of infection. Blood samples with anti-RBD antibody levels in the highest quintile (≥5850 BAU/mL) were associated with a lower rate of subsequent infection (aHR 0.40; 95% CI 0.23, 0.72) compared to samples with RBD levels below the threshold of detection. Conclusions: COVID-19 vaccines continued to provide protection against infection with SARS-CoV-2 through December 2023. Infection following exposure to people with SARS-CoV-2 occurred in a variety of venues indicating the need to practice intervention strategies when the potential for transmission is high.

Longevity and Clinical Effectiveness of the Humoral and Cellular Responses to SARS-CoV-2 Vaccination in Hemodialysis Patients

P-662 Introduction: Individual-level exposure assessments used for large population epidemiological analyses or risk assessments of air pollution health effects most often use pollution levels at residential address to indicate exposure. For individuals working away from home or attending school, using pollution levels at residential location only may cause exposure misclassification and undermine subsequent analyses. A spatial exposure simulation model (SESM) was used to investigate the effects of commuting on exposure in working and non-working populations in Vancouver, British Columbia as part of the Border Air Quality Study. Methods: The SESM simulates working and non-working populations in census tracts by randomly sampling from time-activity patterns and distributions of pollution levels in six microenvironments: indoor residential, indoor other, outdoor, indoor work, commute, and other travel. Unlike other simulation models using this approach, the SESM uses a geographic information system to create the distributions for sampling, and provides output for each census tract in the study area rather than one result for the entire region. We use census data to identify commute destinations for each census tract. Exposure to nitrogen dioxide (NO2) was simulated for one 24-hour period, as it indicates traffic-related air pollution and there is a consistent gradient from high (urban core) to low (suburban fringe) in our study area. Results: The SESM results show that for the day simulated, workers have a different risk of exposure to ambient NO2 than non-workers living in the same census tract, and that risk may be higher or lower depending on geographic location. Exposure risk in the urban core is higher overall, but, for example, 75 percent of the workers in a census tract located in the urban core have a lower risk of exposure than non-workers in the same census tract, while 60 percent of workers in a suburban census tract have higher risk compared to non-workers (Figure 1). Male and female non-workers do not show significant differences in risk of exposure in any census tract. Figure 2 shows the difference in exposure risk at the 90th percentile between workers and non-workers for selected census tracts.FigureFigureDiscussion: Using pollution levels at residential location introduces significant exposure misclassification for working populations. Nonworking populations may also be misclassified to a lesser degree. The SESM provides map-able results for every census tract in the study area, thus highlighting where misclassification errors occur, the spatial distribution of exposure risk, and where targeted policy may have the greatest impact. Figure 1. Cumulative frequency distribution for a census tract 20 km away from the urban and a census tract in the urban core Figure 2. Map showing the difference in exposure risk at the 90th percentile between workers and nonworkers for selected census tracts

A quantitative assessment of the risk of exposure to bovine spongiform encephalopathy via meat-and-bone meal in Japan

Three-dose vaccination-induced immune responses protect against SARS-CoV-2 Omicron BA.2: a population-based study in Hong Kong

Breakthrough infection shapes humoral immunity against SARS-CoV-2 Omicron Variant

Approximately 12% of girls and young women in the United States pledge abstinence. Yet most break their pledges, engaging in first intercourse before marriage. The extant literature reports few differences between pledge breakers and nonpledgers in sexually transmitted infections and nonmarital pregnancies. The present research maintains that previous studies may have obscured important differences in exposure risk and hypothesizes that female pledge breakers who have higher exposure risk are more likely to experience human papillomavirus (HPV) and nonmarital pregnancies. To test this hypothesis, this study uses the National Longitudinal Study of Adolescent to Adult Health, logistic regression, and event history modeling. The results show that, after accounting for differences in exposure risk, pledge breakers have higher risk of HPV and nonmarital pregnancy. As a set, the results are consistent with the argument that pledgers use condoms and contraceptives less consistently and highlight unintended consequences of abstinence promotion.

Rates and modulators of SARS-CoV-2 vaccine nonresponse and breakthrough infections remain unclear in serially vaccinated transplant recipients. In a prospective, mono-centric, observational study, 1878 adult solid organ and hematopoietic cell transplant recipients, with prior SARS-CoV-2 vaccination, were included between March 2021 and February 2022. SARS-CoV-2 anti-spike IgG antibodies were measured at inclusion and details on SARS-CoV-2 vaccine doses and infection were collected. No life-threatening adverse events were reported after a total of 4039 vaccine doses. In transplant recipients without prior SARS-CoV-2 infection (n = 1636), antibody response rates ranged widely, from 47% in lung transplant to 90% in liver transplant and 91% in hematopoietic cell transplant recipients after third vaccine dose. Antibody positivity rate and levels increased after each vaccine dose in all types of transplant recipients. In multivariable analysis, older age, chronic kidney disease and daily dose of mycophenolate and corticosteroids were negatively associated with antibody response rate. Overall rate of breakthrough infections was 25.2% and mainly (90.2%) occurred after third and fourth vaccine dose. Lung transplant recipients had the highest rates of severe breakthrough infection (10.5%) and death (2.5%). In multivariable analysis, older age, daily dose of mycophenolate and corticosteroids were associated with severe breakthrough infection. Transplant recipients with infection before first vaccine dose (n = 160) had higher antibody response rates and levels after each vaccine dose, and a significantly lower overall rate of breakthrough infections compared to those without prior infection. Antibody response after SARS-CoV-2 vaccination and rate of severe breakthrough infections vary largely between different transplant types and are modulated by specific risk factors. The observed heterogeneity supports a tailored approach against COVID-19 in transplant recipients.

Background: Novel coronavirus (COVID-19) first came to China in December 2019 and had become a public health emergency. There was a sudden rise of COVID-19 cases and its deaths. Aims and Objectives: This study intends to study the estimation of breakthrough infection among COVID-19 patients and to estimate the vaccination effectiveness among COVID-19 patients concerning the severity of the disease. Materials and Methods: This study was conducted in Mc Gann teaching hospital. The patients who were attending the Ayush Triage were included in the study. The sample size of 200 was estimated and the study was conducted for July 5–August 4, 2021, (1 month). A retrospective study design was planned and ethical board clearance was taken before starting the study. Patients were interviewed by telephone. The basic information such as contact number was collected by secondary data available in the triage center. Later details about Vaccination status and outcome of the disease were collected through telephonic interviews. Results: Among 200 COVID-19 patients, 28.5% of the patients had taken vaccination. The breakthrough (COVID-19 patients who had taken both doses) infection rate was 10.5% among the people who had been diagnosed with the COVID-19 infection. Most breakthrough infections were mild. The majority of the 163 (81.50%) did not know the source of infection. The majority of the patients 143 (71.50%) were not vaccinated. After the COVID-19 infection, only around 12 (6%) patients were not recovered completely, that is, they had a history of death or hospitalization, and the remaining 188 (94%) patients were completely recovered. Conclusion: Overall, one in every tenth individual after complete vaccination against COVID-19 infection had contracted the infection. Most of the breakthrough infections were mild and many of the subjects did not know the source of the infection.

Background: Novel coronavirus (COVID-19) first came to China in December 2019 and had become a public health emergency. There was a sudden rise of COVID-19 cases and its deaths. Aims and Objectives: This study intends to study the estimation of breakthrough infection among COVID-19 patients and to estimate the vaccination effectiveness among COVID-19 patients concerning the severity of the disease. Materials and Methods: This study was conducted in Mc Gann teaching hospital. The patients who were attending the Ayush Triage were included in the study. The sample size of 200 was estimated and the study was conducted for July 5–August 4, 2021, (1 month). A retrospective study design was planned and ethical board clearance was taken before starting the study. Patients were interviewed by telephone. The basic information such as contact number was collected by secondary data available in the triage center. Later details about Vaccination status and outcome of the disease were collected through telephonic interviews. Results: Among 200 COVID-19 patients, 28.5% of the patients had taken vaccination. The breakthrough (COVID-19 patients who had taken both doses) infection rate was 10.5% among the people who had been diagnosed with the COVID-19 infection. Most breakthrough infections were mild. The majority of the 163 (81.50%) did not know the source of infection. The majority of the patients 143 (71.50%) were not vaccinated. After the COVID-19 infection, only around 12 (6%) patients were not recovered completely, that is, they had a history of death or hospitalization, and the remaining 188 (94%) patients were completely recovered. Conclusion: Overall, one in every tenth individual after complete vaccination against COVID-19 infection had contracted the infection. Most of the breakthrough infections were mild and many of the subjects did not know the source of the infection.

BackgroundCOVID-19 messenger RNA (mRNA) vaccines have demonstrated efficacy and effectiveness in preventing symptomatic COVID-19, while being relatively safe in trial studies. However, vaccine breakthrough infections have been reported.ObjectiveThis study aims to identify risk factors associated with COVID-19 breakthrough infections among fully mRNA-vaccinated individuals.MethodsWe conducted a series of observational retrospective analyses using the electronic health records (EHRs) of the Columbia University Irving Medical Center/New York Presbyterian (CUIMC/NYP) up to September 21, 2021. New York City (NYC) adult residences with at least 1 polymerase chain reaction (PCR) record were included in this analysis. Poisson regression was performed to assess the association between the breakthrough infection rate in vaccinated individuals and multiple risk factors—including vaccine brand, demographics, and underlying conditions—while adjusting for calendar month, prior number of visits, and observational days in the EHR.ResultsThe overall estimated breakthrough infection rate was 0.16 (95% CI 0.14-0.18). Individuals who were vaccinated with Pfizer/BNT162b2 (incidence rate ratio [IRR] against Moderna/mRNA-1273=1.66, 95% CI 1.17-2.35) were male (IRR against female=1.47, 95% CI 1.11-1.94) and had compromised immune systems (IRR=1.48, 95% CI 1.09-2.00) were at the highest risk for breakthrough infections. Among all underlying conditions, those with primary immunodeficiency, a history of organ transplant, an active tumor, use of immunosuppressant medications, or Alzheimer disease were at the highest risk.ConclusionsAlthough we found both mRNA vaccines were effective, Moderna/mRNA-1273 had a lower incidence rate of breakthrough infections. Immunocompromised and male individuals were among the highest risk groups experiencing breakthrough infections. Given the rapidly changing nature of the SARS-CoV-2 pandemic, continued monitoring and a generalizable analysis pipeline are warranted to inform quick updates on vaccine effectiveness in real time.

Introduction: Coronavirus Disease 2019 (COVID-19) vaccines have an important role in the control and prevention of the pandemic. However, infection after vaccination, though uncommon, has been reported after partial or complete immunization. This study aims to find out vaccine breakthrough infection after the Covishield COVID-19 vaccine. Method: This cross-sectional survey was conducted among the health care workers (HCWs) from May 2021 to July 2021 at Patan Hospital, Patan Academy of Health Sciences, Nepal who received the Covishield vaccine. The data were collected using Google form and a printed questionnaire on COVID 19 breakthrough infection ≥2w after vaccination. The rate of breakthrough infection, hospitalization, and its association with age, gender, and working departments of HCWs was analyzed using SPSS. Ethical approval was obtained. Result: Out of 1462 HCWs approached, 880 completed the survey, among which 819 (93.1%) had a completed vaccination status. Infection after the first and before the second dose was 164 (18.7% of 880) and after two doses 131 (16%). The breakthrough infection occurred in 83 (10.1% of 819). There was no statistically significant association of breakthrough infection with age, gender, and working department of HCWs. Total 74 (8.4%) were managed by admission in hospital. Conclusion: The findings of this study reveal a low breakthrough infection rate after Covishield vaccination among HCWs at Patan Academy of Health Sciences, Kathmandu, Nepal. Overall, COVID-19 infection rates decreased after the first and second dose of the vaccine.

Immunogenicity after second and third mRNA-1273 vaccination doses in patients receiving chemotherapy, immunotherapy, or both for solid tumours.

Host sex is an important source of heterogeneity in the severity of epidemics. Pinpointing the mechanisms causing this heterogeneity can be difficult because differences in behaviour among sexes (e.g. greater territorial aggression in males) can bias exposure risk, obfuscating the role of immune function, which can lead to differences in pathology, in driving differential susceptibility between sexes. Thus, sex-biased transmission driven by differences in immune function independent of behaviour is poorly understood, especially in non-mammalian systems. Here we examine the previously unexplored potential for male-biased pathology to affect transmission using an avian host-pathogen system. We employ a sex-dependent multistate transmission model parameterized with isolated, individual-based experimental exposures of domestic canaries and experimental transmission data of house finches. The experiment revealed that male birds have shorter incubation periods, longer recovery periods, higher pathogen burdens and greater disease pathology than females. Our model revealed that male-biased pathology led to epidemic size rapidly increasing with the proportion of male birds, with a nearly 10-fold increase in total epidemic size from an all-female to an all-male simulation. Our results demonstrate that female-biased resistance, independent of male behaviour, can drive sex-dependent transmission in wildlife, indicating that sex-based differences in immune function, not just differences in exposure risk, can shape epidemic dynamics.