Longitudinal investigation of a single variant SARS-CoV-2-outbreak in the immunologically naïve population of Ulvik, Norway

Abstract

Purpose To perform an extensive investigation of the clinical features and long-term complications among the n = 134 adults and children with nucleic acid amplification test (NAAT) verified SARS-CoV-2-infection in the immunologically naïve population of Ulvik, Norway, during the single variant B.1.1.7 outbreak in late January through February 2021. Methods Every infected person regardless of whether symptoms of COVID-19 were present was invited to answer a web-based questionnaire at two- and seven months after testing positive. The period from initial infection to the first questionnaire was assessed retrospectively, and the time points at two- and seven months were assessed prospectively. Results A total of 87 of 134 (65%) NAAT-positive persons answered the first questionnaire, of which 35/87 (40%) were children, and 74 of 87 (85%) answered the second questionnaire. Children experienced symptoms less often than adults during the acute phase of infection (51% (18/35) versus 81% (42/52) (p = .004)). At two-months follow-up 88% (53/60) of participants with symptoms during the acute phase, including all children, reported no longer having symptoms. Among those with persisting symptoms at seven months, fatigue (18/25) and insomnia (16/24) were common. Conclusion In an immunologically naïve population infected with the SARS-CoV-2 B.1.1.7 variant, the clinical features of acute phase symptoms were similar to previous studies. Children underwent asymptomatic infection more often than adults, and adults more often experienced persisting symptoms. Insomnia and fatigue were common complaints among those with persisting symptoms seven months after infection.