Time of Day of Vaccination Affects SARS-CoV-2 Antibody Responses in an Observational Study of Health Care Workers

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global crisis with unprecedented challenges for public health. Vaccinations against SARS-CoV-2 have slowed the incidence of new infections and reduced disease severity. As the time of day of vaccination has been reported to influence host immune responses to multiple pathogens, we quantified the influence of SARS-CoV-2 vaccination time, vaccine type, participant age, sex, and days post-vaccination on anti-Spike antibody responses in health care workers. The magnitude of the anti-Spike antibody response is associated with the time of day of vaccination, vaccine type, participant age, sex, and days post-vaccination. These results may be relevant for optimising SARS-CoV-2 vaccine efficacy.

Time of day of vaccination affects SARS-CoV-2 antibody responses in an observational study of healthcare workers

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global crisis with unprecedented challenges for public health. Vaccinations against SARS-CoV-2 have slowed the incidence of new infections and reduced disease severity. As the time-of-day of vaccination has been reported to influence host immune responses to multiple pathogens, we quantified the influence of SARS-CoV-2 vaccination time, vaccine type, age, sex, and days post-vaccination on anti-Spike antibody responses in healthcare workers. The magnitude of the anti-Spike antibody response associated with the time-of-day of vaccination, vaccine type, participant age, sex, and days post vaccination. These results may be relevant for optimizing SARS-CoV-2 vaccine efficacy.

Is WHO International Standard for Anti-SARS-CoV-2 Immunoglobulin Clinically Useful?

ABSTRACTBackgroundThe introduction of vaccination against SARS-CoV-2 infection needs precise instruments for quality control of vaccination procedure, detection of poor immunological response and estimation of the achieved protection against the disease but also against infection and being infective.ObjectiveTo compare new automated SARS-CoV 2 Ig assay performance characteristics from the automated Elecsys SARS-CoV-2 S (Roche) with the new LIAISON® SARS-CoV-2 TrimericS IgG (DiaSorin) assay and their compatibility with WHO International Standard for anti-SARS-CoV-2 immunoglobulin. In the context of the mass vaccination programs, we undertook the investigation of clinical utility of the two new automated assays by analyzing results in samples collected at specified time points relative to the vaccination time.DesignProspective assay evaluation.PatientsMedical staff undergoing vaccination with BioNTech/Pfizer Comirnaty vaccine between January and March 2021 (n = 79) and referred for serum antiSARS-CoV 2 Ig testing prior to vaccination, 21 days after the first dose, and 8, 14 and 30 days after the second dose. Main Outcome Measure(s): Serum antibody levels measured with Roche and DiaSorin assays.ResultsIntra-assay imprecision was low with DiaSorin at 3.46%; and Roche at 2.5%. The Passing-Bablok regression equation for all tested samples was y (DiaSorin) = 184.61 + (1.03 x Roche) and the correlation between the assays (r=0.587; p < 0.0001).ConclusionsThe novel automated assays exhibit strong concordance in calibration, with assay-specific interpretation required for routine clinical use. These results highlight the need for further work on the international standard of measurement of SARS-CoV 2 Ig especially in era of vaccination. The serological assays can be useful to detect IgG/IgM antibodies, to assess the degree of immunization, to trace the contacts, and to support the decision to readmit people to work or vaccinate them again. However, the values generated by both assays can be markedly different, and assay-specific and personalized interpretation is required.

IMVAMUNE® and ACAM2000® Provide Different Protection against Disease When Administered Postexposure in an Intranasal Monkeypox Challenge Prairie Dog Model

The protection provided by smallpox vaccines when used after exposure to Orthopoxviruses is poorly understood. Postexposu re administration of 1st generation smallpox vaccines was effective during eradication. However, historical epidemiological reports and animal studies on postexposure vaccination are difficult to extrapolate to today’s populations, and 2nd and 3rd generation vaccines, developed after eradication, have not been widely tested in postexposure vaccination scenarios. In addition to concerns about preparedness for a potential malevolent reintroduction of variola virus, humans are becoming increasingly exposed to naturally occurring zoonotic orthopoxviruses and, following these exposures, disease severity is worse in individuals who never received smallpox vaccination. This study investigated whether postexposure vaccination of prairie dogs with 2nd and 3rd generation smallpox vaccines was protective against monkeypox disease in four exposure scenarios. We infected animals with monkeypox virus at doses of 104 pfu (2× LD50) or 106 pfu (170× LD50) and vaccinated the animals with IMVAMUNE® or ACAM2000® either 1 or 3 days after challenge. Our results indicated that postexposure vaccination protected the animals to some degree from the 2× LD50, but not the 170× LD5 challenge. In the 2× LD50 challenge, we also observed that administration of vaccine at 1 day was more effective than administration at 3 days postexposure for IMVAMUNE®, but ACAM2000® was similarly effective at either postexposure vaccination time-point. The effects of postexposure vaccination and correlations with survival of total and neutralizing antibody responses, protein targets, take formation, weight loss, rash burden, and viral DNA are also presented.

Depletion-of-susceptibles bias in influenza vaccine waning studies: how to ensure robust results

Vaccine effectiveness studies are subject to biases due to depletion-of-persons at risk of infection, or at especially high risk of infection, at different rates from different groups (depletion-of-susceptibles bias), a problem that can also lead to biased estimates of waning effectiveness, including spurious inference of waning when none exists. An alternative study design to identify waning is to study only vaccinated persons, and compare for each day the incidence in persons with earlier or later dates of vaccination to assess waning in vaccine protection as a function of vaccination time (namely whether earlier vaccination would result in lower subsequent protection compared to later vaccination). Prior studies suggested under what conditions this alternative would yield correct estimates of waning. Here we define the depletion-of-susceptibles process formally and show mathematically that for influenza vaccine waning studies, a randomised trial or corresponding observational study that compares incidence at a specific calendar time among individuals vaccinated at different times before the influenza season begins will not be vulnerable to depletion-of-susceptibles bias in its inference of waning as a function of vaccination time under the null hypothesis that none exists, and will – if waning does actually occur – underestimate the extent of waning. Such a design is thus robust in the sense that a finding of waning in that inference framework reflects actual waning of vaccine-induced immunity. We recommend such a design for future studies of waning, whether observational or randomised.

Parental Approach to the Prevention and Management of Fever and Pain Following Childhood Immunizations: A Survey Study

Antipyretic analgesics are commonly used to prevent and treat adverse events following immunizations. Current practice discourages routine use due to possible blunting of vaccine immune responses. We surveyed 150 parents/caregivers of recently vaccinated 6- and 15-month-old children to determine the prevalence of and beliefs regarding antipyretic analgesics use around vaccinations. 11% used them prophylactically, before vaccination. Use in the first 48 hours after vaccination was 64%, primarily to prevent and/or treat fever and pain. Acetaminophen was administered 2.6 times more frequently than ibuprofen. Ibuprofen was used more in the 15-month compared with the 6-month-old children (28% vs 7.4%, respectively, P = .001). The majority of caregivers disagreed with their use for fever (53%) or pain (59%). Antipyretic analgesic use, including prophylaxis, around vaccinations was common in our study population. Effective interventions are needed to target parents/caregivers to eliminate unnecessary antipyretic analgesic use around vaccination time and foster nonmedication alternatives.

Reasons for measles cases not being vaccinated with MMR: investigation into parents' and carers' views following a large measles outbreak

SUMMARYUptake rates for the combined measles, mumps and rubella (MMR) vaccine have been below the required 95% in the UK since a retracted and discredited article linking the MMR vaccine with autism and inflammatory bowel disease was released in 1998. This study undertook semi-structured telephone interviews among parents or carers of 47 unvaccinated measles cases who were aged between 13 months and 9 years, during a large measles outbreak in Merseyside. Results showed that concerns over the specific links with autism remain an important cause of refusal to vaccinate, with over half of respondents stating this as a reason. A quarter stated child illness during scheduled vaccination time, while other reasons included general safety concerns and access issues. Over half of respondents felt that more information or a discussion with a health professional would help the decision-making process, while a third stated improved access. There was clear support for vaccination among respondents when asked about current opinions regarding MMR vaccine. The findings support the hypothesis that safety concerns remain a major barrier to MMR vaccination, and also support previous evidence that experience of measles is an important determinant in the decision to vaccinate.