
Symptom‐based case definitions for COVID‐19: Time and geographical variations for detection at hospital admission among 260,000 patients
Author(s) -
Baruch Joaquin,
Rojek Amanda,
Kartsonaki Christiana,
Vijayaraghavan Bharath K. T.,
Gonçalves Bronner P.,
Pritchard Mark G.,
Merson Laura,
Dunning Jake,
Hall Matthew,
Sigfrid Louise,
Citarella Barbara W.,
Murthy Srinivas,
Yeabah Trokon O.,
Olliaro Piero
Publication year - 2022
Publication title -
influenza and other respiratory viruses
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.743
H-Index - 57
eISSN - 1750-2659
pISSN - 1750-2640
DOI - 10.1111/irv.13039
Subject(s) - medicine , case fatality rate , covid-19 , disease control , cohort , disease , demography , pediatrics , family medicine , emergency medicine , epidemiology , environmental health , infectious disease (medical specialty) , sociology
Case definitions are used to guide clinical practice, surveillance and research protocols. However, how they identify COVID‐19‐hospitalised patients is not fully understood. We analysed the proportion of hospitalised patients with laboratory‐confirmed COVID‐19, in the ISARIC prospective cohort study database, meeting widely used case definitions. Methods Patients were assessed using the Centers for Disease Control (CDC), European Centre for Disease Prevention and Control (ECDC), World Health Organization (WHO) and UK Health Security Agency (UKHSA) case definitions by age, region and time. Case fatality ratios (CFRs) and symptoms of those who did and who did not meet the case definitions were evaluated. Patients with incomplete data and non‐laboratory‐confirmed test result were excluded. Results A total of 263,218 of the patients (42%) in the ISARIC database were included. Most patients (90.4%) were from Europe and Central Asia. The proportions of patients meeting the case definitions were 56.8% (WHO), 74.4% (UKHSA), 81.6% (ECDC) and 82.3% (CDC). For each case definition, patients at the extremes of age distribution met the criteria less frequently than those aged 30 to 70 years; geographical and time variations were also observed. Estimated CFRs were similar for the patients who met the case definitions. However, when more patients did not meet the case definition, the CFR increased. Conclusions The performance of case definitions might be different in different regions and may change over time. Similarly concerning is the fact that older patients often did not meet case definitions, risking delayed medical care. While epidemiologists must balance their analytics with field applicability, ongoing revision of case definitions is necessary to improve patient care through early diagnosis and limit potential nosocomial spread.