Following SARS-CoV-2 infection, some patients experience a range of long-lasting symptoms, with a specific burden on their lives and ability to work.

We describe the prevalence and impact of persistent symptoms pre-/post-vaccination in SIREN study participants.

A cross-sectional study of SARS-CoV-2 positive participants was carried out within SIREN, a frequently tested UK healthcare worker cohort with vaccination and demographic data available. Participants with a SARS-CoV-2 positive PCR or anti-SARS-CoV-2 sample between 01 March 2020 and 31 September 2022 were asked via a questionnaire about symptoms and days absent from work following infection. Responses were excluded if infection dates were inconsistent with study records or missing key data. Symptom type/duration and whether infection occurred pre-/post-vaccination and during which variant period were described. Logistic regression was used to estimate factors associated with persistent symptoms (>12 weeks), adjusting for vaccination and demographic factors. The median days absent from work were also determined.

Of 16,599 invitations, 6677 participants responded, and 5053 were included in the analysis. The prevalence of persistent symptoms (symptoms lasting over 12 weeks) differed by infection episode; highest for first infections (32.7%; 1557/4767) compared to second (21.6%; 214/991) and third infections (21.6%; 16/74). Most frequently reported symptoms were fatigue, tiredness, shortness of breath and difficulty concentrating. A higher prevalence of persistent symptoms was reported during the Wild-type variant period compared to the other variant periods (52.9% Wild-type vs. 20.7% Omicron, for any symptom reported during their first infection). Overall, persistent symptoms were higher among unvaccinated participants (unvaccinated 38.1% vs vaccinated 22.0%). Multivariable analysis showed that participants were less likely to report persistent symptoms in infections occurring after vaccination compared to those with an infection before vaccination in the Alpha/Delta and Omicron periods (Alpha/Delta: adjusted Odds Ratio (aOR) 0.66, CI 95% 0.51–0.87, p = aOR 0.07, CI 95% 0.01–0.65, p = 0.02). About half of participants reported that their persistent symptoms impacted their day-to-day (51.8%) and work-related (42.1%) activities ‘a little’, and 24.0% and 14.4% reported that the impact was ‘A lot’. 8.9% reported they had reduced their working hours, and 13.9% had changed their working pattern.

Persistent symptoms were frequent in our cohort, and there was a reduction in symptom duration in those with multiple infection episodes during later variant periods and post-vaccination. The impact of persistent symptoms resulting in reducing working hours or adjusting working patterns has important implications for workforce resilience. UK healthcare workers were highly exposed during the pandemic, demonstrating a significant burden.