COVID-19 Symptoms by Variant Period in the North Carolina COVID-19 Community Research Partnership, North Carolina, USA

Abstract

T he evolution of SARS-CoV-2 during the CO-VID-19 pandemic has raised interest in evolving disease manifestation and associated severity since early reports of its emergence in December 2019 (1). As SARS-CoV-2 variants have evolved, studies have focused on the differences in hospitalizations and deaths (2,3). Although case reports have described changes in symptoms, they are limited in scope and duration of follow-up (4-8). Moreover, because these retrospective case investigations are often event based, separating novel symptoms from preinfection symptoms is subject to recency bias (9), and does not establish a true distribution of these symptoms, unlike prospective syndromic surveillance. The purpose of this study was to describe the evolution of COVID-19 symptoms and their duration during each variant wave in the North Carolina COVID-19 Community Research Partnership (NC-CCRP), a multisite longitudinal symptom and serosurveillance study in North Carolina, USA, that included results from an electronic daily symptom survey regardless of infection status. The StudyThe NC-CCRP is one of the largest and longest running syndromic surveillance surveys of a convenience cohort in the United States. In the study, a total of 37,820 adult participants completed daily health and symptom logs during April 2020-April 2022 and captured 5,480 self-reported COVID-19 infections (10). Adults >18 years of age were recruited from the patient populations served by healthcare systems at 6 North Carolina sites via direct email outreach. Participants received a brief daily electronic survey by text or email to answer questions about COVID-19 exposures, symptoms, test results, receipt of vaccination, and risk behaviors. We obtained demographic information and healthcare worker occupation at baseline. Participants provided informed consent electronically. We defined variant periods as pre-Delta, Delta, and Omicron (pre-BA.4/BA.5) based on variant predominance in North Carolina (Figure 1). We defined symptomatic COVID-19 as the presence of >1 new symptom 2 weeks before or after the date of a self-reported positive viral test. A new symptom occurred if the symptom was not present in the 7 days before the report date. We defined reinfection as a positive test result >90 days after a previous positive test.

COVID‐19‐Associated Chemosensory Loss Continues to Decline

“…Recent studies have shown changing symptomatology of COVID‐19 infection, with each virus variant “wave” demonstrating varying clinical features 7‐9 . Though considered a disease‐defining symptom, decreasing incidence of olfactory disturbance was demonstrated with data from the powerful N3C database 3 —findings corroborated by subsequent studies using differing means 4,10 .…”

Prevalence of Olfactory Dysfunction with the Omicron Variant of SARS-CoV-2: A Systematic Review and Meta-analysis

“…2). Twenty-five studies were from populations primarily of European ancestry [9,30,38-60], seventeen studies on East Asians [61-77] (note that one of these studies, [75], reports on the same cohort as [74], and therefore was removed from the meta-analysis), eight studies on South Asians [79-86], four studies on Latinos/Hispanics [87-90], five studies on populations in Africa [91-95], and three studies from the Middle East [96-98]. The location of studies, with the prevalence indicated by the color intensity, and the cohort size indicated by the size of the circles, shows that Western countries report the highest prevalence, while studies from East Asia and the Middle East report the lowest prevalence (Fig.…”

Analysis of the transmission rate of SARS-CoV-2 Omicron subvariants BA.5.2 and BF.7 based on COVID-19 surveillance data.

“…11 In my opinion, its in uence on the accuracy of the results of the two online questionnaire surveys was very limited. In the rst online questionnaire survey, the emerging symptoms of most of residents, such as cough, fever, fatigue, muscle or body aches, or sore throat, 12 were hard to be explained by common upper respiratory tract infection during the two weeks. On the other hand, if the symptoms emerged after family members had a con rmed diagnosis of COVID-19, the resident had an extremely high probability of COVID-19 infection.…”