key: cord-0940273-ppfxkyx9
authors: Hughes, Gerry; Merry, Concepta; Geary, Una; Noonan, Nóirín; Bergin, Colm
title: Changing Disease Epidemiology to Inform Expanded Coronavirus Disease 2019 Testing
date: 2020-11-26
journal: Clin Infect Dis
DOI: 10.1093/cid/ciaa1677
sha: 8bf8aff650af25d522aa08e9e0a2e2f49033838d
doc_id: 940273
cord_uid: ppfxkyx9

nan

To the Editor-We read with interest the recent article by Lucey et al [1] in which they describe coronavirus disease 2019 (COVID-19) transmission events between healthcare workers and patients and among healthcare workers themselves.

The authors reference a change in their local testing criteria that was expanded to include healthcare workers with symptoms of sore throat and headache. This followed concern that some healthcare workers with COVID-19 could be experiencing milder symptoms that did not meet the previous criteria for testing. This is a point that we feel deserves further discussion. Research from our own center shows that headache, in particular, but also nasal congestion and sore throat are significantly more common than someof the symptoms listed in the EuropeanCentre for Disease Prevention and Control(ECDC) COVID-19 case definition. This finding could have a significant impact for COVID-19 testing guidelines both nationally and internationally.

At the time that the author's institution changed their testing criteria, the ECDC placed emphasis on the symptoms of fever, cough, and shortness of breath in their case definition for COVID-19. Sudden-onset anosmia, ageusia, or dysgeusia has since been added to their case definition [2]. National guidelines from the Health Protection and Surveillance Centre in Ireland mirrors these recommendations [3] .

At St. James's Hospital, a large tertiary teaching hospital also located in Dublin, Ireland, all outpatients with a diagnosis of COVID-19 were invited to complete a symptom survey during the acute phase of their illness between April 2020 and June 2020. A total of 295 individual participants responded; 91% of respondents were healthcare workers. The most common reported symptoms included tiredness (79%), headache (72%), generalized pains and aches (64%), altered sensation of taste (59%), and altered sensation of smell (58%). A full list of reported symptoms and their frequency are shown in Figure 1 .

There were 259 responses to the surveyfrom 183 unique individuals during the first 7 days following onset of symptoms. Twenty-four of these responses (9%) did not include any of the clinical criteria of the current ECDC COVID-19 case definition (fever, dyspnea, cough, anosmia/ageusia/dysgeusia). However, of these 24 responses, 21 (88%) did include headache, nasal congestion, or sore throat (or a combination). Several other studies have demonstrated nosocomial transmission of COVID-19 [4, 5] and asymptomatic carriage among healthcare workers [6, 7] .

Given the potential for unrecognised COVID-19 transmission (particularly in healthcare settings), we suggest that consideration be given to including headache, nasal congestion, and sore throat in the COVID-19 case definition for symptomatic individuals, as well as a formal recommendation to introduce, where possible, regular reverse-transcription polymerase chain reaction screening among healthcare workers during times of high disease prevalence and new infection waves. 

Health Protection Surveillance Centre. COVID-19 case definitions

Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China

Nosocomial transmission of COVID-19: a retrospective study of 66 hospital-acquired cases in a London teaching hospital

COVID-19: PCR screening of asymptomatic healthcare workers at London hospital

Screening of healthcare workers for SARS-CoV-2 highlights the role of asymptomatic carriage in COVID-19 transmission