mRNA and Protein Subunit COVID-19 Vaccine Reactogenicity and the Relationship to Productivity for Healthcare Workers and First Responders

ObjectivesTo compare the percentage of participants that experienced any solicited systemic reactogenicity symptom after one dose of the updated 2024-2025 adjuvanted protein-based Novavax (NVX; JN.1) or Pfizer-BioNTech mRNA (PFZ; KP.2) COVID-19 vaccine within 2- and 7-days post-vaccination and examine its disrupting impact on daily life. MethodsIn this prospective, interventional, real-world study (SHIELD/NCT06633835), previously vaccinated healthcare workers (HCWs) and first responders (FRs) from Salt Lake City, Utah, USA, and surrounding areas self-selected to receive NVX or PFZ. At 2- and 7-days post-vaccination, participants self-reported on 11 vaccine-related reactogenicity symptoms and functional impairment using a 5-item modified Sheehan Disability Scale. Results588 participants completed the Day 2 questionnaire (NVX, n=219; PFZ, n=369); 583 completed the Day 7 questionnaire (NVX, n=217; PFZ, n=366). Two-days post-vaccination, NVX recipients were less likely to report a systemic (OR=0.40; 95% CI, 0.21-0.75) or local (OR=0.10; 95% CI, 0.30-0.33) reactogenicity symptom and lost 50% fewer work hours (0.7 vs 1.4 h) and 66% fewer productive hours (0.8 vs 2.4 h) than PFZ recipients. There was little to no difference between vaccines at 7-days post-vaccination. ConclusionFewer reactogenicity symptoms following COVID-19 vaccination suggest use of the NVX vaccine as an immunization option with a lower disruption to daily life.