Symptom-based early-stage differentiation between SARS-CoV-2 versus other respiratory tract infections-Upper Silesia pilot study

Abstract

In the DECODE project, data were collected from 3,114 surveys filled by symptomatic patients RT-qPCR tested for SARS-CoV-2 in a single university centre in March-September 2020. The population demonstrated balanced sex and age with 759 SARS-CoV-2( +) patients. The most discriminative symptoms in SARS-CoV-2( +) patients at early infection stage were loss of taste/smell (OR = 3.33, p < 0.0001), body temperature above 38℃ (OR = 1.67, p < 0.0001), muscle aches (OR = 1.30, p = 0.0242), headache (OR = 1.27, p = 0.0405), cough (OR = 1.26, p = 0.0477). Dyspnea was more often reported among SARS-CoV-2(-) (OR = 0.55, p < 0.0001). Cough and dyspnea were 3.5 times more frequent among SARS-CoV-2(-) (OR = 0.28, p < 0.0001). Co-occurrence of cough, muscle aches, headache, loss of taste/smell (OR = 4.72, p = 0.0015) appeared significant, although co-occurrence of two symptoms only, cough and loss of smell or taste, means OR = 2.49 (p < 0.0001). Temperature > 38℃ with cough was most frequent in men (20%), while loss of taste/smell with cough in women (17%). For younger people, taste/smell impairment is sufficient to characterise infection, whereas in older patients co-occurrence of fever and cough is necessary. The presented study objectifies the single symptoms and interactions significance in COVID-19 diagnoses and demonstrates diverse symptomatology in patient groups.

Figure 1

Results of statistical analysis. Panel A stacked bar plots showing frequencies of symptoms regarding COVID-19 diagnosis. Symptoms having a higher odds ratio in SARS-CoV-2 infected patients were shown. Panel B odds ratio for all symptoms and coexisting diseases with 95% confidence intervals. The red line shows the level of odds ratio equal to 1. Significant odds ratios were coloured green.

Figure 2

Heatmap with correlation coefficients for pairwise comparison of queries. Blood type was ignored due to different interpretation of the effect size coefficient. Comparisons with at least a small effect size have been coloured, i.e. values of correlation within the range (− 0.1, 0.1) were left blank.

Figure 3

Frequency of patients observing one symptom or a combination of symptoms regarding the total number of patients from a certain group (infected or not infected with SARS-CoV-2) who answered all four analysed queries. Dots in the middle part indicate which symptom or combination of symptoms the bars in the upper part of the plot refer to. For example, about 15% of patients with negative COVID-19 diagnosis reported only cough (and no high temperature, no dyspnea, no loss of taste/smell), whereas, from the group of patients with a positive diagnosis, about 11% of patients reported only cough (no other symptoms from the list). The lower part of the plot shows the odds ratio with 95% confidence intervals for comparison of SARS-CoV-2 diagnosis with a corresponding symptom or symptom combination. The red line shows the level of odds ratio equal to 1. Significant odds ratios (p < 0.05) were coloured green.

Figure 4

Frequency of patients observing one symptom or a combination of symptoms regarding the total number of patients from a certain group (infected or not infected with SARS-CoV-2) who answered all four analysed queries, considered in two age subsets. Dots in the middle part indicate which symptom or combination of symptoms the bars in the upper part of the plot refer to. The lower part of the plot shows an odds ratio with 95% confidence intervals for comparison of SARS- CoV-2 diagnosis with a corresponding symptom or symptoms combination. The red line shows the level of odds ratio equal to 1. Significant odds ratios were coloured green.