Low incidence and severity of SARS-CoV-2 infections in people with PCD

ABSTRACT

Background: There is little data on SARS-CoV-2 infections in people with rare diseases. We studied incidence and severity of SARS-CoV-2 in people with primary ciliary dyskinesia (PCD). Method(s) We used data from COVID-PCD, an international participatory study including people with PCD, which started recruitment on 30.05.2020. Participants completed weekly online questionnaires on SARS-CoV-2 infections and symptoms. We studied severity of infections reported at baseline or during follow-up while we calculated incidence rates including only infections reported during follow-up. We used Cox proportional hazard regression to study predictors of getting infected. Result(s) By January 23, 2022, 726 people participated (40% male, median age 27 years;range 0-85). 90% of persons above 14 years have been vaccinated against COVID-19 and most (93%) wore facemasks in public. Only 62 (8.5%) had a confirmed SARS-CoV-2 infection. Severity of disease was mainly mild;11 (18%) were asymptomatic, 47 (76%) had symptoms among whom 4 (6%) were hospitalized (none in the ICU, nobody died). Severity of disease was not associated with age, sex, co-morbidity or vaccination. We had follow-up data from 651 (90%). During 633 person-years of follow-up (median 59 weeks per person), 43 incident SARS-CoV-2 infections were reported (incidence rate 6.9 per 100 person years;95% CI 5.2-9.2). Children (0-14 years) had a higher risk of infection (hazard ratio 3.0;95% CI 1.3-6.8) compared to 15-49 year-olds. Conclusion(s) SARS-CoV-2 incidence rates remained low and severity mainly mild in people with PCD, probably reflecting high vaccination rate and personal protective behaviour.