Are COVID-19 mRNA vaccine side effects severe enough to cause missed work? Cross-sectional study of health care-associated workers

Burden and Impact of Reactogenicity among Adults Receiving COVID-19 Vaccines in the United States and Canada: Results from a Prospective Observational Study

As SARS-CoV-2 variants continue to emerge, vaccination remains a critical tool to reduce the COVID-19 burden. Vaccine reactogenicity and the impact on work productivity/daily activities are recognized as contributing factors to vaccine hesitancy. To encourage continued COVID-19 vaccination, a more complete understanding of the differences in reactogenicity and impairment due to vaccine-related side effects across currently available vaccines is necessary. The 2019nCoV-406 study (n = 1367) was a prospective observational study of reactogenicity and associated impairments in adults in the United States and Canada who received an approved/authorized COVID-19 vaccine. Compared with recipients of mRNA COVID-19 booster vaccines, a smaller percentage of NVX-CoV2373 booster recipients reported local and systemic reactogenicity. This study's primary endpoint (percentage of participants with ≥50% overall work impairment on ≥1 of the 6 days post-vaccination period) did not show significant differences. However, the data suggest that NVX-CoV2373 booster recipients trended toward being less impaired overall than recipients of an mRNA booster; further research is needed to confirm this observed trend. The results of this real-world study suggest that NVX-CoV2373 may be a beneficial vaccine option with limited impact on non-work activities, in part due to the few reactogenicity events after vaccination.

Vaccination, time lost from work, and COVID-19 infections: a Canadian healthcare worker retrospective cohort study

The COVID-19 pandemic highlighted hurdles for healthcare delivery and personnel globally. Vaccination has been an important tool for preventing severe illness and death in healthcare workers (HCWs) as well as the public at large. However, vaccination has resulted in some HCWs requiring time off work post-vaccination to recover from adverse events. We aimed to understand which HCWs needed to take time off work post-vaccination, for which vaccine types and sequence, and how post-vaccination absence impacted uptake of booster doses in a cohort of 26,267 Canadian HCWs. By March 31, 2022, more than 98% had received at least two doses of the approved COVID-19 vaccines, following a two-dose mandate. We found that recent vaccination and longer intervals between doses were associated with significantly higher odds of time-loss, whereas being a medical resident and receiving the BNT162b2 vaccine were associated with lower odds. A history of lab-confirmed SARS-CoV-2 infection was associated with lower odds of receiving a booster dose compared with no documented infection, aOR 0.61 (95% CI: 0.55, 0.68). Similarly, taking sick time following the first or second dose was associated with lower odds of receiving a booster dose, aOR 0.83 (95% CI: 0.75, 0.90). As SARS-CoV-2 becomes endemic, the number and timing of additional doses for HCWs requires consideration of prevention of illness as well as service disruption from post-vaccination time-loss. Care should be taken to ensure adequate staffing if many HCWs are being vaccinated, especially for coverage for those who are more likely to need time off to recover.

Intradermal delivery of a quadrivalent cell-based seasonal influenza vaccine using an adjuvanted skin patch vaccination platform

All seasonal influenza vaccines for 2021-2022 in the US were quadrivalent and the market continues to be dominated by intramuscular delivery of non-adjuvanted, virion-derived antigens grown in chicken eggs. Up to four new egg-adapted production influenza vaccine strains must be generated each year. The introduction in 2012 of Flucelvax®, which is grown in mammalian suspension cell culture and uses vaccine production strains without adaptive mutations for efficient growth in eggs, represented a major advance in vaccine production technology. Here we demonstrate that Flucelvax can be reformulated and combined with a liposomal adjuvant containing QS-21 (Verndari Adjuvant System 1.1, VAS1.1) or QS-21 and 3D-PHAD (VAS1.2) for intradermal administration using a painless skin patch, VaxiPatch™. VAS1.2 is similar to AS01_B, the adjuvant system used in Shingrix® and Mosquirix™. We show that Flucelvax, when reformulated and concentrated using tangential flow filtration (TFF), maintains hemagglutination and single radial immunodiffusion (SRID) potency. Loading the reformulated Flucelvax material onto VaxiPatch arrays conferred high levels of resistance to heat stress and room temperature stability. TFF enriched vaccine antigens were combined with VAS1.1 or VAS1.2 and dispensed in 10nL drops into the pockets of 36 (total 360 nL) stainless steel microneedles arranged in a microarray 1.2 cm in diameter. Using VaxiPatch delivery of 2 µg of antigen, we demonstrated intramusuclar-comparable IgG and hemagglutination inhibition (HAI) immune responses in Sprague Dawley® rats. With addition of VAS1.2, antigen-specific IgG titers were increased as much as 68-fold (47-fold for VAS1.1) with improvements in seroconversion for three of four strains (all four were improved by VAS1.1). TFF-reformulated antigens combined with VAS1.1 or VAS1.2 and delivered by VaxiPatch showed only minor skin reactogenicity after 1 h and no skin reactogenicity after 24 h. These data indicate that VaxiPatch and the VAS system have the potential to be transformative for vaccine delivery.

Covid-19 vaccination reported side effects and hesitancy among the Syrian population: a cross-sectional study

INTRODUCTION

Studying post-vaccination side effects and identifying the reasons behind low vaccine uptake are pivotal for overcoming the pandemic.

METHODS

This cross-sectional study was distributed through social media platforms and face-to-face interviews. Data from vaccinated and unvaccinated participants were collected and analyzed using the chi-square test, multivariable logistic regression to detect factors associated with side effects and severe side effects.

RESULTS

Of the 3509 participants included, 1672(47.6%) were vaccinated. The most common reason for not taking the vaccine was concerns about the vaccine's side effects 815(44.4). The majority of symptoms were mild 788(47.1%), followed by moderate 374(22.3%), and severe 144(8.6%). The most common symptoms were tiredness 1028(61.5%), pain at the injection site 933(55.8%), and low-grade fever 684(40.9%). Multivariable logistic regression analysis revealed that <40 years (vs. ≥40; OR: 2.113, p-value = 0.008), females (vs. males; OR: 2.245, p-value< .001), did not receive influenza shot last year (vs. did receive Influenza shot last year OR: 1.697, p-value = 0.041), AstraZeneca (vs. other vaccine brands; OR: 2.799, p-value< .001), co-morbidities (vs. no co-morbidities; OR: 1.993, p-value = 0.008), and diabetes mellitus (vs. no diabetes mellitus; OR: 2.788, p-value = 0.007) were associated with severe post-vaccine side effects. Serious side effects reported were blood clots 5(0.3%), thrombocytopenia 2(0.1%), anaphylaxis 1(0.1%), seizures 1(0.1%), and cardiac infarction 1(0.1%).

CONCLUSION

Our study revealed that most side effects reported were mild in severity and self-limiting. Increasing the public's awareness of the nature of the vaccine's side effects would reduce the misinformation and improve the public's trust in vaccines. Larger studies to evaluate rare and serious adverse events and long-term side effects are needed, so people can have sufficient information and understanding before making an informed consent which is essential for vaccination.

Impact of Sex and Age on mRNA COVID-19 Vaccine-Related Side Effects in Japan

mRNA COVID-19 vaccination was initiated worldwide in late 2020, and its efficacy has been well reported. However, studies about vaccine-related side effects are sparse. A total of 262 health care workers who received mRNA COVID-19 vaccine BNT162b2 were recruited, and their vaccine-related side effects were investigated. Impact of sex and age on the side effects was statistically analyzed. A higher number of vaccine-related side effects among females versus males was identified (median 3 versus 2, P < 0.05, after the first dose, and 5 versus 2.5, P < 0.01, after the second dose). General fatigue, headache, chills, and fever were the culprit adverse symptoms. In multivariate analysis, females had an increasing number of side effects after receiving their first (B = 0.7; 95% confidence interval [CI], 0.2 to 1.2) and second (B = 1.5; 95% CI, 0.7 to 2.2) vaccine doses compared to that of males. In age analysis, the older group (≥60 years old) had a lower number of side effects than the younger group (B = -0.5 with a 95% CI of -1.1 to -0.02 after the first vaccine dose, and B = -2.1 with a 95% CI of -2.9 to -1.2 after the second vaccine dose). Additionally, prolonged time to recovery was found among females (P = 0.003 after the first dose; P = 0.008 after the second dose). Specifically, symptoms of general fatigue, headache, itching, swelling at the injection site, and dizziness were the culprit symptoms affecting recovery time. Several cutaneous and membranous symptoms, including "COVID arm," were identified among females. These results highlight the impact of sex and age on side effects from mRNA COVID-19 vaccine and will aid in creating a safer vaccine. IMPORTANCE We demonstrate sex- and age-related impact on mRNA COVID-19 vaccine-related side effects, with a higher number and frequency of side effects and prolonged time to recovery in females compared to males and negative correlation between age and vaccine-related side effects. Identification of unique age- and sex-specific adverse symptoms will provide the opportunity to better understand the nature of sex- and age-associated immunological differences and develop safer and more efficacious vaccines.

Side Effects after mRNA COVID-19 Vaccine as a Booster in Health Workers

Background

In Indonesia, around 400 health workers died due to Covid-19 between June-July 2021, therefore the health workers need to be given further immunity. Health workers were among the first to get a booster shoot. However, they may experience side effects after vaccination. We aimed to describe side effects of Moderna vaccine as a booster in health workers.

Methods

A cross sectional study was conducted on health workers who received mRNA Covid-19 vaccine booster (Moderna) at Sulianti Saroso Infectious Disease Hospital, Indonesia and had filled the questionnaire assessing side effects form. We associated the form of the questionnaire assessing side effects from the originating source of hospital immunization unit in September 2021.

Results

A total of 101 health workers who received mRNA Covid-19 vaccine booster in Jul-Aug 2021 were included. Most of health worker experienced more than 3 side effects. The side effects were sore arm (100%); chills (72%); fatigue (57%); headache (53%) and fever (51%), other symptoms (28%). The side effects mostly happened a day of receiving a booster shot (61.4%). There was no association between age, gender, comorbid to amount of side effects (P>0.05).

Conclusion

Since the public must fulfil the immunization program during pandemic, it is the responsibility of the healthcare provider to inform about the potential side effects and benefits of a new Covid-19 vaccine.