133 Molesworth Street
PO Box 5013
Wellington 6140
New Zealand
T+64 4 496 2000
14 October 2021
Paul McKenna
By email: [FYI request #16428 email]
Ref:
H202113156
Tēnā koe Paul
Response to your request for official information
Thank you for your request under the Official Information Act 1982 (the Act) on 27 September
2021 for:
1. Does each row in the CSV file supplied relate to one 'case'? one test result deemed
positive? or something else? Please clarify (Some rows have one test result, others
have up to 6).
Each row in the file is the available results from one case.
2. I understand that each positve (sic) test result is validated by repeat analysis, yet many
rows have only one Ct value. Is this the highest, lowest or average value out of 2? Or
was there no repeat anaylisis? (sic) If not why would this occur?
The Ct values provided are all of the values the Ministry holds for each case.
Case definition does not require validation through a repeat analysis.
Laboratory definitive evidence requires at least one of the following:
•
detection of SARS-CoV-2 from a clinical specimen using a validated NAAT (PCR).
Very weak positive results wil only be labelled a confirmed case when the result is
confirmed on a second sample.
•
detection of coronavirus from a clinical specimen using pan-coronavirus NAAT (PCR)
and confirmation as SARS-CoV-2 by sequencing
•
significant rise in IgG antibody level to SARS-CoV-2 between paired sera.
There is more information at:
www.health.govt.nz/our-work/diseases-and-conditions/covid-19-
novel-coronavirus/covid-19-information-health-professionals/case-definition-and-clinical-testing-
guidelines-covid-19#case.
3. Some rows have multiple sets of 2 results (up to 3 sets). Does this reflect; multiple tests
obtained at various times throughout infection? 2-3 separate cases? or something else?
Each row in the file is the available results from one case.
4. Many Cts are very high and would not normally be considered positive. What protocol is
used to determine these to be actual SARS-CoV-2 infections?
5. Many postive (sic) test results use an Envelope (E) gene assay. Since E-gene assays
have been shown to lack specificity, particularly in relation to other coronaviruses, what
measure have been used to ensure these are not false positives?
Please refer to the response to question 2 above.
I trust this fulfils your request. Under section 28(3) of the Act, you have the right to ask the
Ombudsman to review any decisions made under this request. The Ombudsman may be
contacted by email at:
[email address] or by calling 0800 802 602.
Please note that this response, with your personal details removed, may be published on the
Ministry of Health website at:
www.health.govt.nz/about-ministry/information-releases.
Nāku noa, nā
Gill Hall
Group Manager, Science and Insights
COVID-19 Health System Response
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