133 Molesworth Street
PO Box 5013
Wellington 6140
New Zealand
T+64 4 496 2000
11 October 2021
Vonny Marsh
By email: [FYI request #16612 email]
Ref:
H202111751
Tēnā koe Vonny
Response to your request for official information Thank you for your request under the Official Information Act 1982 (the Act) to the Ministry of
Health (the Ministry) on 03 September 2021 for information in relation to influenza like illnesses
(ILI) and COVID-19.
You will find a response to each part of your request below.
“How many cases of influenza like illnesses (please detail both excluding and
including covid19 cases) have been notified in NZ for 2020.”
Unlike COVID-19, ILIs are not notifiable. They are reported by components of the surveillance
system for influenza and other respiratory illnesses through the following:
• Healthline
• Healthstat
• GP sentinel surveillance
• Severe acute respiratory illness (SARI), a subset of ILIs reported by sentinel hospitals in
the Auckland region.
• Flutracking
SARI and GP sentinel surveillance are the only components that test for influenza and
respiratory viruses. In 2020, COVID-19 testing was mostly done in designated COVID testing
centres. ILI and SARI rates were low in 2020 due to the COVID-19 response.
Information relating to ILIs can be found on the Institute of Environmental Research and
Science (ESR) influenza dashboards, available at:
www.esr.cri.nz/our-services/consultancy/flu-
surveillance-and-research. Information on COVID-19 notifications is publicly available on the New Zealand COVID-19
dashboard www.esr.cri.nz/our-expertise/covid-19-response/new-esr-full-width-pagethe-new-
zealand-covid-19-intelligence-dashboard/ Information on current cases is available on the
Ministry’s website at:
www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-
coronavirus/covid-19-data-and-statistics/covid-19-current-cases#case-details.
“What percentage of these cases were diagnosed as the flu and what percentage of these
were diagnosed as Covid19?”
The Ministry does not hold the exact number of influenza cases in 2020. Only four cases were
picked up from hospital surveillance and do not represent the number of influenza cases in New
Zealand.
Most of the COVID-19 cases were diagnosed following the COVID case definition criteria and
testing put in place for COVID-19 only. Information on COVID-19 cases can be found on the
websites above.
“What months would you consider the flu season?”
The start and end of the flu season are variable and depend on the year. The peak influenza
season is usually around July/August.
“During the 2020 flu season, per 100,000 people, what was the average number of cases
(please detail both including and excluding covid19) per week notified?”
As above, ILIs are not notifiable diseases. Weekly rates of general practice ILI consultations per
100,000 are available on ESR’s influenza dashboard at:
www.esr.cri.nz/our-
services/consultancy/flu-surveillance-and-research.
“what was the range of this info (for the 2020 flu season what was the highest reported
cases per week per 100,000, and what was the lowest number of cases per week per
100,000 notified.... for both excluding and including Covid 19)”
As above, information on highest and lowest reported cases per 100,000 people can be found
on ESR’s influenza dashboard.
The table below outlines the lowest and highest weekly cases per 100,000 people, average
weekly cases per 100,000 and the total number of cases as of 3 September 2021 for COVID-
19.
Year Lowest weekly cases Highest weekly cases Average weekly cases
Total
per 100,000
per 100,000
per 100,000
cases
2020 0
10.28
0.98
2165
2021 0.18
9.4
0.88
1583
“How many cases of influenza like illnesses (please detail both excluding and including
covid19 cases) have been hospitalized in NZ for 2020?”
In 2020, there were 76 hospitalisations of COVID-19 cases.
The Ministry does not hold information in relation to hospitalisation for ILIs. Surveillance
information on SARI (ie, hospitalised ILI), is available on ESR’s influenza dashboard.
“How many people died of any influenza strain in 2020, how many died of Covid19 in
2020?”
There have been no reports of death from influenza for 2020.
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Information relating to mortality rates is collected as part of the Ministry’s mortality dataset. In
2020, there was 25 deaths from COVID 19.
You requested:
“info for 2021 to date, 2019, 2018 and 2017.”
Rates of general practice ILI consultations for 2021 are publicly available on ESR’s influenza
dashboard at:
www.esr.cri.nz/our-services/consultancy/flu-surveillance-and-research. Rates for
2017-2019 are available at:
www.esr.cri.nz/our-services/consultancy/flu-surveillance-and-
research/2017-new-zealand-influenza-intelligence-dashboard. As of 3 September 2021, there has been one death and 198 hospitalisations due to COVID-19.
I trust this information 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 website at:
www.health.govt.nz/about-ministry/information-releases/responses-official-
information-act-requests. Nāku noa, nā
Jane Chambers
Acting Deputy Director- General
Population Health and Prevention
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