Changes in the trajectory of Long Covid symptoms following COVID-19 vaccination: community-based cohort study

Abstract

Objective: To estimate associations between COVID-19 vaccination and Long Covid symptoms in adults who were infected with SARS-CoV-2 prior to vaccination. Design: Observational cohort study using individual-level interrupted time series analysis. Setting: Random sample from the community population of the UK. Participants: 28,356 COVID-19 Infection Survey participants (mean age 46 years, 56% female, 89% white) aged 18 to 69 years who received at least their first vaccination after test-confirmed infection. Main outcome measures: Presence of long Covid symptoms at least 12 weeks after infection over the follow-up period 3 February to 5 September 2021. Results: Median follow-up was 141 days from first vaccination (among all participants) and 67 days from second vaccination (84% of participants). First vaccination was associated with an initial 12.8% decrease (95% confidence interval: -18.6% to -6.6%) in the odds of Long Covid, but increasing by 0.3% (-0.6% to +1.2%) per week after the first dose. Second vaccination was associated with an 8.8% decrease (-14.1% to -3.1%) in the odds of Long Covid, with the odds subsequently decreasing by 0.8% (-1.2% to -0.4%) per week. There was no statistical evidence of heterogeneity in associations between vaccination and Long Covid by socio-demographic characteristics, health status, whether hospitalised with acute COVID-19, vaccine type (adenovirus vector or mRNA), or duration from infection to vaccination. Conclusions: The likelihood of Long Covid symptoms reduced after COVID-19 vaccination, and the improvement was sustained over the follow-up period after the second dose. Vaccination may contribute to a reduction in the population health burden of Long Covid, though longer follow-up time is needed.

COVID-19 in non-hospitalised adults caused by either SARS-CoV-2 sub-variants Omicron BA.1, BA.2, BA.5 or Delta associates with similar illness duration, symptom severity and viral kinetics, irrespective of vaccination history

“…These results are consistent with self-reported symptom data during the BA.1 wave from the ZOE study, a large smartphone app-based community study in the UK and are supportive of the expansion of cardinal symptoms by the NHS in its COVID-19 guidance issued in April 2022 (13,15). Despite analyses of hospitalisation and mortality data indicating that Omicron caused lesssevere clinical disease (7,8,10), our data suggests that COVID-19 continues to cause a significant symptom burden in non-hospitalised adults with COVID-19, with attendant impacts on healthcare resources, and incidence of post-COVID syndrome (PCS) (11,12). This continued burden is well-illustrated by the shift in the numbers of asymptomatic cases we .…”

Risk of Long Covid in people infected with SARS-CoV-2 after two doses of a COVID-19 vaccine: community-based, matched cohort study

“…Conclusions based on healthcare records rather than self-report (as in our study) are less clear, with vaccination associated with reduced rates of only specific symptoms [5] and diagnoses [9], though under-presentation, under-diagnosis, and under-recording are all possible [10]. In addition to reducing the risk of Long Covid after breakthrough infection, evidence also suggests that the likelihood and severity of pre-existing Long Covid symptoms may be reduced after vaccination [11,12].…”

Long COVID: A growing problem in need of intervention

“…The UK Office for National Statistics published self-reported data from patients indicating that the first dose of vaccination reduced the risk of long COVID by 13% and the second dose by an additional 9%. 11 A study of US veterans found that prolonged symptoms (>28 days) were significantly less frequent in vaccinated (5%) than unvaccinated persons (11%). 12 Another study, currently only available as preprint, 13 comparing 9,479 vaccinated COVID-19 patients to unvaccinated matched controls, found a protective effect of vaccines on severity and clinical outcome of the acute illne ss but no difference in the risk of long COVID.…”