Impact of COVID-19 Vaccination with BNT162b2 on the Frequency of Acute Symptoms Among Symptomatic US Adults Testing Positive for SARS-CoV-2 at a National Retail Pharmacy

OBJECTIVES: This study characterized the frequency of acute COVID-19 symptoms by original monovalent BNT162b2 COVID-19 vaccine status.

METHODS: Symptomatic US adults testing positive for SARS-CoV-2 at CVS Health were recruited between 01/31-04/30/2022 (CT.gov: NCT05160636). Self-reported socio-demographics, clinical characteristics and vaccination status were evaluated. Self-reported systemic, respiratory, and gastrointestinal symptoms were assessed at enrollment, Week 1 and 4 after testing. Frequency of individual and total number of symptoms (0, 1–2, 3–5, 6+) were compared across BNT162b2 vaccination status (boosted: >2 doses, primed: 2 doses and unvaccinated) using chi-square test (or Fisher’s exact test, if cell count <5) for categorical variables, and t-test or Wilcoxon rank-sum test for quantitative outcomes.

RESULTS: 371 participants included 94 (25%) Boosted, 90 (22%) Primed, and 197 (53%) Unvaccinated. Mean age was 42.4, 76% were female, 24.2% had ≥1 comorbidity, 38.8% prior infection. In vaccinated groups, mean (SD) time since vaccination was 186 (105) days. All symptoms are represented in mean (SD). At enrollment, Boosted reported 4.7 (2.5) symptoms versus 5.8 (2.5) and 5.6 (2.7) in Primed and Unvaccinated, respectively (p=0.01). At Week 1, Boosted reported 2.1 (1.5) symptoms versus 2.8 (2.2) and 3.2 (2.4) in Primed and Unvaccinated (p=0.0008). At Week 4, Boosted reported 1.0 (1.2) symptoms versus 1.5 (1.5) and 1.7 (1.9) in Primed and Unvaccinated (p=0.005). Among Boosted, four and six out of twelve symptoms were less often reported at enrollment and Week 1, respectively, with largest differences observed for fever, chills, muscle/body aches. Three out of eight symptoms were less often reported by Boosted at Week 4, with largest differences for headache, diarrhea, and loss of taste/smell. Compared with Primed and Unvaccinated, Boosted had lower total symptom burden across all time points (p<0.005).

CONCLUSIONS: Participants boosted with BNT162b2 self-reported the fewest acute symptoms, reaffirming the value of being up-to-date with COVID-19 vaccination.