Date publication:
20 January 2022
Destined audience:
General public
Context
Omicron COVID-19, the variant of concern, has been found to be highly transmissible in the community despite high vaccination rates. This means that a high incidence of cases is expected to continue for a considerable time.
The testing capacity of PCR is limited. It has been further constrained due to inability for samples to be pooled given high positivity rates, high impact of community transmission on staff infections, furlough periods and supply chain constraints (e.g. for reagents
COVID-19 management currently relies on timely laboratory-PCR testing notification. The increased turnaround time for collection, PCR tests and results will lead delays in linkage to care and specific therapies and the identification of high-risk individuals. Rapid antigen testing is now being used more as a diagnostic tool than a screening test. Rapid antigen testing will require new methods to identify patients and contacts. This will ensure that patients at higher risk for severe disease and those who would benefit from treatment interventions are connected to care. PCR testing with the appropriate turnaround times will also be necessary.
Proposed use for rapid antigen testing (RAT).
The following three purposes can be served by rapid antigen tests:
- This test is used as a diagnostic alternative to PCR for COVID-19-prone individuals. A positive rapid antigen test should be considered a diagnosis for COVID-19 in most cases, especially in this high-prevalence environment.
- To manage outbreaks.
- To aid in the early identification of cases in high risk settings.
1 Using RAT to diagnose COVID-19-high risk patients as an alternative test to PCR
|
Cohort |
Recommendation for Testing |
Comment |
|---|---|---|
|
People who reside in a household with a known COVID-19 Case |
Positive RAT should not be taken as a confirmation of COVID-19, regardless of symptoms. |
Employers should have a risk management program in place to ensure safe delivery of services.
|
|
People who have been exposed to a COVID-19case at high risk |
||
|
Symptomatic people (who have not been exposed to high-risk substances) |
Positive RAT should not be considered confirmed COVID-19. |
|
2 Using RAT for managing outbreaks
|
Cohort |
Recommendation for Testing |
Comment |
|---|---|---|
|
High-risk environments (healthcare, aged and disability care, correctional institutions) |
To determine the initial extent of a facility’s capacity, RAT testing can be used. |
Confirmatory PCR testing for the initial case only. Day 6 and Day 12 of the RAT will be used to assess the outbreak progress. Day 12 swab to declare outbreak over may be PCR. |
|
Other industries, businesses, organizations, etc. |
Staff may be tested for RATs to determine the extent of transmission in work environments. |
Industry should think about how they will respond to COVID-19 epidemics in their workplace. This may include a daily RAT to staff and other controls already in place. |
3 Using RAT to detect cases in high-risk environments early
|
Cohort |
Recommendation for Testing |
Comment |
|---|---|---|
|
High community prevalence in residential aged and disability care facilities |
|
This regime is subject to local consideration regarding community prevalence and availability. |
|
Healthcare settings that manage very high-risk patients (e.g. Haematology unit, transplant ward, oncology ward, renal dialysunit |
||
|
Other critical services (e.g. Other critical services (e.g. |
In certain circumstances, consult with the Health authorities |
The appropriate regime will be determined by the industry and setting. It should be able to manage business continuity of supply/service. However, other risk mitigants might be able to adequately manage risks. RAT may also be used in addition to these. |
|
Other industries, businesses, organizations, etc. |
Not recommended |
Industry may decide to review and institute surveillance testing in accordance with its individual industry risk assessment. |
