COVID-19 PCR Testing Backlog: Rapid Review

Published online: 
14 June 2022
COVID-19 PCR Testing Backlog: Rapid Review.

Since the beginning of the Delta outbreak in August 2021, laboratories undertaking COVID-19 testing and the Ministry of Health (the Ministry) Directorate coordinating the health system response have been under considerable strain. This strain built on close to 18 months of operational response and significant workloads starting in March 2020. As the Delta outbreak waned in late 2021, Omicron was identified as a new variant of concern and New Zealand began to adapt its response plan accordingly. The Government’s three-phase Omicron response set out a staged approach of changes to testing, contact tracing, and isolation requirements, gradually moving from PCR testing as the primary methodology to Rapid Antigen Tests (RATs) primarily in Phase 3.

As part of response planning, the Ministry’s Testing and Supply Group in the COVID-19 Health Response Directorate worked with laboratories to understand existing capacity for PCR testing and support plans to increase capacity. A goal of 60,000 tests per day nationally was identified and efforts were undertaken to achieve this by the end of March 2022, including by procuring additional equipment. Regular reporting of capacity indicated to decision makers that laboratories were on track to achieving this level of capacity. However, there were issues with the definition of capacity that led to misinterpretation of the system’s ability to respond to a surge in Omicron cases.

The first case of community transmission of Omicron in New Zealand was reported on 18 January 2022. Demand for testing, the proportion of positive tests, and case numbers began to increase rapidly. By the middle of February 2022, some laboratories were becoming overwhelmed, and a backlog of PCR tests began to build. By 1 March 2022, a backlog of 32,000 samples older than five days had built up that laboratories advised would be destroyed due to their reduced clinical relevance and/or viability. However, as New Zealand had shifted to Phase 3 of the Omicron response, laboratories were able to free up capacity and processed the backlog by mid-March 2022.

In this context, Allen + Clarke was commissioned by the Ministry in March 2022 to undertake an independent rapid review of the circumstances leading to the backlog of PCR testing and the apparent gap between the system’s forecast capacity and its actual ability to respond to the Omicron surge.

Publishing information

  • Date of publication:
    14 June 2022
  • ISBN:
  • Citation:
    Allen + Clarke. 2022. COVID-19 PCR Testing Backlog: Rapid review. Wellington: Ministry of Health.
  • Ordering information:
    Only soft copy available to download
  • Copyright status:

    Owned by the Ministry of Health and licensed for reuse under a Creative Commons Attribution 4.0 International Licence.

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