By Public Health Expert 09/10/2021


Prof Nick Wilson, Dr Jennifer Summers, Prof Michael Baker*

The NZ Government appears to have drifted into an unclear strategic approach to Covid-19 control. In this blog we outline one potential way forward: a regional strategic approach that considers “regional suppression” and “regional elimination”. To maximise the success of this strategy, NZ would need to ensure tighter internal borders. Fortunately, there are examples from five Australian states and territories that show that successful internal border control of Covid-19 is possible. 

Until very recently, Aotearoa NZ was clearly using an elimination strategy for Covid-19 control. Also, the Government had released (in August 2021) a fairly clear approach to Reconnecting New Zealanders to the World. The latter was also based on continuing the elimination strategy (for at least the short-term), while achieving high vaccine coverage; and increasing connections with the world to allow larger numbers of New Zealanders to safely enter the country.

The current Delta variant outbreak in Auckland (with spread into parts of the Waikato and possibly Northland), has resulted in somewhat unclear strategic messaging from the NZ Government. Our best guess is that the Government has shifted to a “regional suppression” strategy for Auckland, while still trying for “regional elimination” in the rest of NZ. But it has used unclear phrasing around “transitioning” away from elimination without specifying the new strategy that will replace it. This situation is uncharacteristic given the Government’s impressive record in strategic clarity, coherent policies, and effective public communication throughout the pandemic.

Here we outline a potential strategic direction to support a coherent programme of interventions that could minimise the adverse health impact of Covid-19. A further specific advantage of this approach is that if the Covid-19 outbreak in Auckland deteriorates, then healthcare resources can be shifted to Auckland from Covid-19-free regions of the country (eg, additional ICU nurses and doctors moving into Auckland).

If successful, this approach could help NZ fully resume its “Reconnecting” plan which includes achieving high vaccine coverage and then a phased increase in travel in and out of the country.

Suggested strategic framework for regional control of Covid-19

Region Suggested strategic approach Details
Northland “Regional elimination” To maximise long-term success the border with Auckland needs to be strengthened (see the text below this table). There might be a risk of cases in Northland following the recent visit of an infected person travelling from Auckland.
Auckland “Regional suppression” but with “regional elimination” potentially becoming more viable as vaccination levels increase If there continues to be progress with vaccination and increased social and economic support is targeted to deprived and marginalised communities (as discussed here), then it is conceivable that the current epidemic in Auckland can still be eliminated in coming months. But failing such action, it is best to assume a future of “regional suppression” where Covid-19 control restrictions are regularly adjusted up and down to minimise healthcare service overload while maximising social and economic activities.
The part of the Waikato currently in Alert Level 3 “Regional elimination” To maximise success, intensive control measures are required along with a hard border around the Alert Level 3 region. This border should comprise a limited number of police checkpoints with all minor roads crossing the border to be blocked in multiple places until elimination is achieved (eg, blocked with containers/concrete blocks). An alternative option would be a hard internal border across the central plateau level of the North Island, as this would involve the need for fewer road blocks and police checkpoints.
Rest of the North Island “Regional elimination” That is maintaining the current Covid-19-free status, but requiring much tighter internal borders with areas with current or potential community transmission.
South Island “Regional elimination” While maintaining its current Covid-19-free status, the South Island could potentially be moved to a lower Alert Level once a tighter border has been established around regions in the North Island with current or potential community transmission. If there is spread to other parts of the North Island in coming weeks and months, then the South Island should have its own tight border around it (and consider the successful lessons from Tasmania – see below).

 

Much tighter internal borders required

To be successful, our proposed strategic framework does require much tighter regional borders around Auckland, around the part of the Waikato under Alert Level 3 restrictions, and potentially Northland if transmission is occurring there. Recommended options for tightening these internal borders include all of the following:

  • Keeping the current requirement for a negative PCR test within 72 hours before crossing the border.
  • Tightening the limits around essential travel – to just “very essential travellers” (eg, with all crossing potentially requiring a border crossing fee to exclude minor reasons for travel).
  • Adding a requirement for full vaccination (ie, two doses of the Pfizer vaccine).
  • Adding a requirement for a negative rapid antigen test at the border that is performed by a health professional (if nasal) or Police (if a saliva test) at the border.
  • There should be large fines and other substantial penalties for any illegal attempts at crossing these internal borders.

 

Do internal borders work?

The internal border around Auckland for the current Delta outbreak has not worked particularly well to date – although we argue this is because it has not been tight enough. Better examples of success come from those Australian states and territories that are maintaining their elimination status despite the large Covid-19 outbreaks in New South Wales (NSW) and Victoria and a growing number of cases in ACT.

Elimination status is being maintained by Queensland, South Australia, Western Australia, Northern Territory and Tasmania with relatively fewer domestic/interstate cases compared to NSW and Victoria. Queensland has had a number of border failures with cases coming in from both NSW and Victoria – but has worked on strengthening the border along with vaccination drives and increasing quarantine facility capacity. South Australia implemented a short state-wide lockdown in July 2021 which helped to keep the number of community cases low; although some recent cases has resulted in snap lockdown in three Local Government Areas. Both Western Australia and the Northern Territory have had experience with Delta cases, but have so far managed to keep locally-acquired case numbers relatively low by both having strong border restrictions.

Tasmania currently has the record in Australia of having over 510 days since a locally-acquired Covid-19 case was detected. Tasmania has the advantage of being an island, but also has developed what is referred to as a ‘Delta Shield’ – which enables local authorities to activate when needed with swift lockdowns, additional state border closures/restrictions and other public health measures such as mask mandates and gathering restrictions. Tasmania has heavily restricted access from travellers who want to enter if travelling from high-risk areas such as NSW, Victoria and even NZ, and a 14-day quarantine requirements from those arriving from medium-risk areas. In this regard, the South Island of NZ could learn from the success of Tasmania’s border controls.

In summary, we have outlined a new regional strategic approach to Covid-19 control that considers “regional suppression” and “regional elimination”. To maximise success of such approaches, a much stronger approach to having tight internal borders would be needed. Fortunately, there are examples from five Australian states and territories that show that successful internal border control is possible.

 

*Author details: All authors are with the Department of Public Health, University of Otago, Wellington.