What we do
About our project
Motivation for projectIn the treatment, care and isolation of COVID-19 patients, one of the most important issues is determining the duration of infectiousness. The current Dutch guideline advises at least 14 days of isolation for seriously ill patients and at least 21 days for intubated patients. It is believed that in most cases this isolation duration is too long.
Aim of projectThe ultimate goal of this project is to produce new evidence-based criteria for the cessation of isolation of hospitalized COVID-19 patients that are safe (very low subsequent risk of transmission to other patients or healthcare workers), and reducing the number of unnecessary days in isolation (thereby improving quality of life of patients, reducing hospital costs, making optimal use of the scarce number of isolation beds and ensuring enough capacity for non-COVID-19 care). Multiple sources of data and evidence will be integrated to arrive at these new criteria.
MethodsThis is a retrospective cohort and technical laboratory study. The main outcome of interest is the probability and the duration of hospitalized COVID-19 patients being infectious, consequently influencing the decision on cessation of isolation. All adult COVID-19 patients tested positive in the 7 participating hospitals identified between the end of February 2020 and December 2021 were eligible for inclusion.
Possible impactThe decision algorithm will be delivered to appropriate committees and institutes that develop and issue IPC guidelines on COVID-19 care, such as the expert group infection prevention COVID-19 of the Federation of Medical Specialists (FMS) who will draft the guidelines for hospitals. Various applicants are member of this FMS expert group. Our results can be used internationally, and could lead to worldwide policy changes.
Our research focus
Work package 1: Patient and healthcare worker data
- To establish patient cohorts on which different end of isolation policies were applied, by assessing historically and currently used COVID-19 isolation policies in Dutch hospitals, and to construct a timeline of Infection Prevention and Control measures.
- To collect and analyse data on the relevant patient, disease, treatment and virus characteristics (e.g. duration of COVID-19 symptoms, undergone interventions (e.g. treatment), viral load kinetics, viral variants, and antibody development) in relation to isolation duration and infectivity in the different established cohorts.
Work package 2: PCR and Antigen-detecting rapid diagnostic test
- To determine the correlation between Ct values of different PCR platforms and isolation of infectious virus, and to establish platform-specific Ct-value cut-offs for non-infectious viral RNA detection.
- To enrich the current datasets by performing additional virological tests on stored surplus diagnostic material.
- To determine the correlation between PCR Ct-values, the quantitative amount of SARS-CoV-2 N-antigen and presence of infectious virus in follow-up respiratory samples, followed by Ag-RDT, to determine the usefulness of Ag-RDT and follow-up PCR in supporting decision-making on cessation of COVID-19 isolation.
- To quantify the accuracy of Ag-RDT test results as compared to other virological test results.
Work package 3: Formulating new criteria
- To develop an improved IPC isolation criteria or algorithm for COVID-19 isolation cessation using results from WP1 and WP2, and directed by international criteria/guidance.
- To generate recommendations and policy how these new criteria can be implemented and how to evaluate its impact and safety in practice.
Funds & Grants
This study is supported by ZonMw (grant number 10430102110003).
- Department of Viroscience, Unit Clinical Virology, Erasmus MC
- University Medical Center Rotterdam, The Netherlands