Symptom Profiles and Progression in Hospitalized and Nonhospitalized Patients With Coronavirus Disease, Colorado, USA, 2020

Grace M. Vahey; Kristen E. Marshall; Emily McDonald; Stacey W. Martin; Jacqueline E. Tate; Claire M. Midgley; Marie E. Killerby; Breanna Kawasaki; Rachel K. Herlihy; Nisha B. Alden; J. Erin Staples


Emerging Infectious Diseases. 2021;27(2):385-395. 

In This Article

Abstract and Introduction


To improve recognition of coronavirus disease (COVID-19) and inform clinical and public health guidance, we randomly selected 600 COVID-19 case-patients in Colorado. A telephone questionnaire captured symptoms experienced, when symptoms occurred, and how long each lasted. Among 128 hospitalized patients, commonly reported symptoms included fever (84%), fatigue (83%), cough (73%), and dyspnea (72%). Among 236 nonhospitalized patients, commonly reported symptoms included fatigue (90%), fever (83%), cough (83%), and myalgia (74%). The most commonly reported initial symptoms were cough (21%–25%) and fever (20%–25%). In multivariable analysis, vomiting, dyspnea, altered mental status, dehydration, and wheezing were significantly associated with hospitalization, whereas rhinorrhea, headache, sore throat, and anosmia or ageusia were significantly associated with nonhospitalization. General symptoms and upper respiratory symptoms occurred earlier in disease, and anosmia, ageusia, lower respiratory symptoms, and gastrointestinal symptoms occurred later. Symptoms should be considered alongside other epidemiologic factors in clinical and public health decisions regarding potential COVID-19 cases.


Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease (COVID-19), was first detected in China in December 2019.[1,2] Within 1 month, COVID-19 cases were reported in numerous countries, including the United States.[3] By the end of January 2020, the World Health Organization (WHO) declared the COVID-19 outbreak a public health emergency of international concern.[4] After WHO's declaration, rapid acceleration of virus transmission in many parts of the world led WHO to characterize COVID-19 as a global pandemic in March.[5] As of December 4, the United States had reported >14 million COVID-19 cases and ≈275,000 associated deaths.[6] The large number of cases and deaths has created an unprecedented burden on the nation's healthcare system, necessitating triage of patients and the prioritization of testing.

Initially, the most common symptoms of COVID-19 were reported to be fever, cough, and dyspnea.[7–9] However, asymptomatic infections and additional symptoms common to other viral respiratory illnesses have been reported, including chills, fatigue, myalgia, sore throat, nasal congestion, rhinorrhea, nausea, vomiting, and diarrhea.[10] Persons with COVID-19 have also reported anosmia (loss of smell) and ageusia (loss of taste) more frequently than with other viral respiratory diseases.[11]

Although ≈80% of persons with COVID-19 experience mild disease,[12] to date most published reports of COVID-19 symptoms are derived from case-series and cross-sectional analyses of medical record reviews, primarily among hospitalized patients. Literature regarding symptoms experienced by nonhospitalized COVID-19 patients is growing, but information summarizing symptom duration, progression, and statistical comparison to hospitalized patients remains limited. To improve COVID-19 disease recognition, which can help mitigate its spread, particularly for mild cases, and inform clinical and public health guidance, we interviewed hospitalized and nonhospitalized COVID-19 patients in Colorado to determine the symptoms they experienced and when these symptoms occurred during their course of illness.