Table 1. COVID-19 interim case definition in place for notification of COVID-19 cases at the time of the study, Ireland, June 2020.

Classification criteria		Definition
Clinical criteriaa		A patient with acute respiratory infection with sudden onset of at least one of the following: cough, feverb, shortness of breath OR sudden onset of anosmiac, ageusiad and dysgeusiae OR with severe acute respiratory infection (SARI) with fever and at least one sign/symptom of respiratory disease, e.g. cough, fever, shortness of breath AND requiring hospitalisation AND with no other aetiology that fully explains the clinical presentation
Epidemiological criteria		A patient with at least one of the following two epidemiological links: close contactf with a confirmed COVID-19 case in the 14 days prior to onset of symptoms OR having been a resident or a staff member in the 14 days prior to onset of symptoms, in a residential institution for vulnerable people where ongoing COVID-19 transmission has been confirmed
Diagnostic imaging criteria		Radiological evidence showing lesions compatible with COVID-19
Laboratory criteria		Detection of SARS-CoV-2 nucleic acid in a clinical specimen
Case classification	Possible case	Any person meeting the clinical criteria
	Probable case	Any person meeting the clinical criteria with an epidemiological link OR meeting the diagnostic imaging criteria
	Confirmed case	Any person meeting the laboratory criteria

COVID-19: coronavirus disease; SARI: severe acute respiratory infection; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2.

^a Clinical judgement should be applied in application of these criteria to determine who requires testing.

^b Fever may be subjective or confirmed by a healthcare worker (≥ 38^◦C).

^c Loss of sense of smell.

^d Loss of sense of taste.

^e Distortion of sense of taste.

^f Close contact is defined as face-to-face contact at < 2 metres for longer than 15 minutes.