Changes in Symptoms Experienced by SARS-CoV-2-Infected Individuals – From the First Wave to the Omicron Variant

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic and public health crisis since the beginning of 2020. First recognized for the induction of severe disease, the virus also causes asymptomatic infections or infections with mild symptoms that can resemble common colds. To provide better understanding of these mild SARS-CoV-2 infections and to monitor the development of symptoms over time, we performed a detailed analysis of self-reported symptoms of SARS-CoV-2 positive and SARS-CoV-2 negative individuals. In an online-based survey, a total of 2117 individuals provided information on symptoms associated with an acute respiratory infection, 1925 of the participants had tested positive for SARS-CoV-2 infection, and 192 had tested negative. The symptoms reported most frequently during the early phases of the pandemic by SARS-CoV-2 infected individuals were tiredness, headache, impairment of smell or taste and dry cough. With the spread of the alpha and delta variants, the frequency of nose symptoms such as blocked or runny nose and sneezing increased to being reported by almost 60% of infected individuals. Interestingly, the spread of the omicron variant brought a sharp decrease in the incidence of impaired sense of smell or taste, which was reported by only 24% in this phase of the pandemic. The constellation of symptoms should be monitored closely in the months ahead, since future SARS-CoV-2 variants are likely to bring about more changes.

Vaccination efficacy against post-COVID-19 symptoms in Delta and Omicron waves: a prospective cohort in East Indonesia

“…Fever remains a consistent symptom over different variants, despite a decreasing trend in reported fever. A study identified that the odds ratios of fever in Delta and Omicron waves were similar [29]. Regarding post-COVID-19 symptoms, people infected in the Delta waves were more likely to experience chronic cough and chronic headache, but the probability of fatigue was similar between variants as shown in Table 3.…”

Pathophysiology of SARS-CoV-2 Infection of Nasal Respiratory and Olfactory Epithelia and Its Clinical Impact

“…Similarly, Vihta et al reported that the Omicron variant had a lesser impact on smell and taste compared with the Delta and Alpha variants [71]. [77] Persistence of OD at Persistence of O 6 months (%) [80,[82][83][84] Recovery Rate of OD overy R (%) [78][79][80][81] Prevalence of OD (%) [58][59][60][61][62] An animal model study further reported that Syrian hamsters inoculated with the Delta variant results in severe necrotizing pan-rhinitis, while the Omicron variant acutely causes rhinitis with epithelial injury but with, of interest, OE sparing [73]. Histological analysis of the olfactory epithelium amongst Delta variant-infected hamsters showed global necrosis extending to the level of basal cells, with otherwise complete dissolution of the normal pseudostratified columnar layering of olfactory neurons and sustentacular cells [73].…”

“…It is interesting that the hospitalization [81][82][83][84], ICU admission [81], and mortality rates [85,86] differ fairly significantly between the different SARS-CoV-2 variants (Table 1). These may once again reflect the differences in susceptibility to different mutations in the SARS-CoV-2 receptor-binding domain, or simply acquired immunity for either infections or previous infections.…”

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

“…It does assess study design and cohort size, as well as information about convenience samples and response rates, when applicable. In addition, we explored the magnitude of the potential bias caused by survey-type studies that rely on the initiative and motivation of respondents [8,[30][31][32] by comparing the results of traditional-design studies with those of survey-type studies. In addition, we generated funnel plots to assess potential publication bias [33].…”

“…2). Twenty-two studies were from populations primarily of European ancestry [8,32,[40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59], eight studies on East Asians [60][61][62][63][64][65][66][67], three studies on South Asians [68][69][70], three studies on Latinos [71][72][73], four studies on populations in Africa [74][75][76][77], and one study from West Asia (Turkey [78]). 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 Africa report the lowest prevalence (Fig.…”