# P-1112. Factors Associated with Symptomatic Upper Respiratory Viral Infection Symptoms and Self-COVID-19 Testing in a Multicentre Irish Healthcare Worker Cohort

## TL;DR

This study examines factors linked to upper respiratory infections and self-testing for COVID-19 among healthcare workers in Ireland.

## Contribution

The study identifies specific variables associated with symptomatic illness and self-testing behavior in healthcare workers.

## Key findings

- Increasing age was associated with symptomatic upper respiratory tract infections.
- Shorter time since last COVID-19 infection was linked to higher likelihood of self-testing.
- Only 63% of symptomatic healthcare workers performed a COVID-19 test.

## Abstract

Healthcare workers (HCWs) are at increased risk of viral upper respiratory tract infections (URTI) & COVID-19 compared to the general population. We utilise a longitudinal HCW study to describe symptomatic URTIs and self-testing for COVID-19 in HCWs, as well as the characteristics associated with developing URTI and subsequent COVID-19 testing.Figure 1:Symptom frequency across the study periodTable 1:Variables associated with symptomatic illnessBetween-group differences assessed using Chi-squared or Wilcoxon ranksum test, as appropriate.

Symptom frequency across the study period

Variables associated with symptomatic illness

Between-group differences assessed using Chi-squared or Wilcoxon ranksum test, as appropriate.

All participants in the Prevalence of COVID-19 in Irish HCWs (PRECISE) study, a longitudinal study across two hospital sites in Ireland (St James’s Hospital, Dublin & University Hospital Galway), were included. Participants completed monthly questionnaires detailing URTI symptoms, vaccines received, and COVID-19 tests taken, as well as demographic, medical and occupation details. Data was collected from September 2024 – February 2025. Univariate analysis assessed variables associated with symptomatic illness, testing for COVID-19, and SARS-CoV-2 infection, with multivariable logistic regression including significant univariate variables and relevant variables identified a priori.Table 2:Multivariable model for factors associated with symptomatic illness and self-testingMultivariable models including significant univariate features and variables selected a priori. Time since last vaccine and time since last infection were z-scored prior to analysis.Table 3:Variables associated with self-testingBetween-group differences assessed using Chi-squared or Wilcoxon ranksum test, as appropriate.

Multivariable model for factors associated with symptomatic illness and self-testing

Multivariable models including significant univariate features and variables selected a priori. Time since last vaccine and time since last infection were z-scored prior to analysis.

Variables associated with self-testing

Between-group differences assessed using Chi-squared or Wilcoxon ranksum test, as appropriate.

There were n=893 participants. Symptoms suggestive of URTI were reported by n=321 (36%) (Figure 1). Symptomatic infection was more likely in participants with a prior COVID-19 infection, but independent of seasonal COVID-19 or Influenza vaccination (Table 1). On multivariable analysis, increasing age was associated with symptomatic episodes (Table 2). Of the n=321 symptomatic HCWs, 202 (63%) performed a COVID-19 antigen test. Females, those with a pre-existing risk factor for COVID infection, and shorter time since most recent COVID infection were associated with increased likelihood of testing (Table 3), while shorter interval since last infection was the only significant variable following multivariable regression (Table 2). 34 of the 202 tests (17%) were positive.

There was a high prevalence of self-reported viral URTI symptoms among HCWs. Increasing age was associated with development of symptomatic illness. More than one-third did not perform a COVID-19 test, with shorter interval since last COVID-19 infection associated with self-testing. This study demonstrates the burden of symptomatic illness in HCWs, and the low rates of self-testing for COVID-19.

All Authors: No reported disclosures