Simple Symptom-Based Prediction of COVID-19: A Single-Center Study of Outpatient Fever Clinic in Japan

Shinji Inaba; Yasuhisa Nakao; Shuntaro Ikeda; Yuki Mizumoto; Takeshi Utsunomiya; Masahiko Honjo; Yasutsugu Takada; Naoyuki Nogami; Eiichi Ishii; Osamu Yamaguchi

doi:10.7759/cureus.36614

Simple Symptom-Based Prediction of COVID-19: A Single-Center Study of Outpatient Fever Clinic in Japan

Cureus. 2023 Mar 24;15(3):e36614. doi: 10.7759/cureus.36614. eCollection 2023 Mar.

Authors

Shinji Inaba^{1

2

3}, Yasuhisa Nakao¹, Shuntaro Ikeda¹, Yuki Mizumoto⁴, Takeshi Utsunomiya⁴, Masahiko Honjo⁵, Yasutsugu Takada⁵, Naoyuki Nogami^{1

2}, Eiichi Ishii⁶, Osamu Yamaguchi¹

Affiliations

¹ Department of Cardiology, Pulmonology, Hypertension and Nephrology, Ehime University Graduate School of Medicine, Toon, JPN.
² Department of Community Medicine, Pulmonology and Cardiology, Ehime University Graduate School of Medicine, Toon, JPN.
³ Department of Cardiology, Imabari City Medical Association General Hospital, Imabari, JPN.
⁴ Department of Surgery, Imabari City Medical Association General Hospital, Imabari, JPN.
⁵ Department of Hepato-Billiary-Pancreatic Surgery, Ehime University Graduate School of Medicine, Toon, JPN.
⁶ Department of Pediatrics, Imabari City Medical Association General Hospital, Imabari, JPN.

Abstract

Introduction: Coronavirus disease 2019 (COVID-19) symptoms are not fully understood in non-hospitalized individuals in Japan, and COVID-19 differentiation by symptoms alone remained challenging. Therefore, this study aimed to examine COVID-19 prediction from symptoms using real-world data in an outpatient fever clinic.

Methods: We compared the symptoms of COVID-19-positive and negative patients who visited the outpatient fever clinic at Imabari City Medical Association General Hospital and tested for COVID-19 from April 2021 to May 2022. This retrospective single-center study enrolled 2,693 consecutive patients.

Results: COVID-19-positive patients had a higher frequency of close contact with COVID-19-infected patients compared with COVID-19-negative patients. Moreover, patients with COVID-19 had high-grade fever at the clinic compared with patients without COVID-19. Additionally, the most common symptom in patients with COVID-19 was sore throat (67.3%), followed by cough (62.0%), which was approximately twice as common in patients without COVID-19. COVID-19 was more frequently identified in patients having a fever (≥37.5℃) with a sore throat, a cough, or both. The positive COVID-19 rate reached approximately half (45%) when three symptoms were present.

Conclusion: These results suggested that COVID-19 prediction by combinations of simple symptoms and close contact with COVID-19-infected patients might be useful and lead to recommendations for testing of COVID-19 in symptomatic individuals.

Keywords: clinical diagnosis of covid-19; covid-19; covid-19 symptoms; general public health; outpatient fever clinic.