Government officials are wary of possible "conversion from passive misinformation to spreading violence" amidst the Covid-19 vaccine rollout.
Documents obtained by the Herald on Sunday also detail how Facebook offered training to those in charge of government social media accounts, on how to handle misinformation.
And Department of Conservation staff were called in to share their experiences of dealing with anti-1080 messages on DoC's social media channels.
New Zealand's vaccine programme is intensifying and so are efforts by opponents who are spreading false information about the Pfizer-BioNTech vaccine - including an anti-Covid vaccine pamphlet drop in Mt Eden this week.
The Herald on Sunday has received documents from DHBs and government agencies about efforts to counter such misinformation.
A "misinformation workshop" was held by the Department of the Prime Minister and Cabinet (DPMC), the hub of government that's leading the Covid-19 response work, in April, with representatives from many of the country's 20 DHBs attending.
A subsequent email to attendees noted points raised in discussion and that would be further developed included, "where there may be conversion from passive misinformation spreading to violence".
There was also talk about mapping misinformation around the country, with the Ministry of Health to take the lead on developing a triaging process for new material or incidents.
Attendees were told they could join an upcoming session where DoC communications staff would "talk about their experience managing anti-1080 sentiment on their channels and how we can learn from that", and that Facebook was offering social media training.
A DPMC Covid-19 response group spokesperson told the Herald on Sunday that "recent research indicates that there is a link between disinformation and violent extremism".
"At this stage there have been no specific incidents or concerns received by DHBs. Currently there is a requirement for all DHBs and providers to ensure site security [at vaccination clinics] and to conduct a site risk assessment."
The government's approach is to provide reliable information to the public, while "strengthening resilience to false misinformation", the spokesperson said.
Anti-vaccine pamphlets have been widely distributed in New Zealand, including this week in Auckland's central suburbs. In response, University of Auckland vaccinologist Associate Professor Helen Petousis-Harris said such tactics used characteristics of propaganda and were "deeply misleading".
"Ultimately people could die as a result of this kind of misinformation. The outcome could be a potentially fatal disease that's now preventable."
Meanwhile, the Medical Council this week warned doctors spreading false information about Covid-19 and vaccines could lose the right to practise medicine. It's investigating complaints, including about an open letter apparently signed by some doctors and which opposed the vaccine over claimed safety concerns.
Medical Council chairman Dr Curtis Walker told RNZ that scientific and medical evidence very strongly supported the Covid-19 vaccine as safe and effective.
"There's a mountain of evidence out there of how effective and safe the Covid vaccine is ... and we've already seen the alternative of unvaccinated populations where millions have died."
No new community cases of Covid-19
Ministers will meet this morning to decide any changes to alert levels, and boosted by the news that so far there are no known community cases linked to the Sydney visitor.
The Ministry of Health announced yesterday that another 2345 tests had been processed in the greater Wellington region, and all returned negative.
That's despite confirmation the man who flew into Wellington on June 19, who subsequently tested positive for Covid-19 after returning to Sydney, had the more infectious Delta variant.
So far, 2213 people have been identified as contacts, of whom 1441 have returned a negative result. Another 764 are being followed up, or awaiting a test result. Eight have been "excluded from testing", the ministry said.
Wellington was put into alert level 2 this week, which will remain in force until at least 11.59pm tonight. Leading scientists have previously told the Herald that positive test results from anyone linked to the Sydney tourist are most likely to have emerged already.
However, more test results will be sent to officials and ministers this morning. A press conference is scheduled for 1pm.