Covid 19 Delta outbreak: Experts answer five questions we're all asking

As Auckland marks its first day at alert level 3, questions abound over whether we've eased restrictions too soon. Can this outbreak still be contained? And what happens if we've got it wrong? Science reporter Jamie Morton put five burning questions to University of Auckland infectious diseases expert Associate Professor Siouxsie Wiles, Otago University senior Māori health researcher Professor Sue Crengle, Otago epidemiologists Professor Michael Baker and Dr Amanda Kvalsvig, and Te Pūnaha Matatini and University of Canterbury Covid-19 modeller Professor Michael Plank.

Has the Government just made a major mistake by moving out of alert level 4, or can we have faith?

Siouxsie Wiles (SW): It's been clear throughout this pandemic that the Government's approach to controlling outbreaks has been to use the least restrictions necessary given the circumstances. We have to remember that they will have more information than us about where transmission is currently happening and will be balancing that against the risk of moving Auckland to level 3. It's clear that level 4 has been extremely effective at getting the outbreak to the stage it is at now. If it hadn't we would be seeing daily cases in the hundreds, maybe even over a thousand a day as has happened in New South Wales.

Sue Crengle (SC): Te Rōpū Whakakaupapa Urutā advocated for Auckland and Waikato to be in level 4 with the rest of the upper North Island - north from Mōkau in the west to Tūranganui-a-Kiwa in the east - under level 3 until the extent of transmission from the three cases in Kaiaua/Whakatīwai could be ascertained. In addition, we are not confident that all of the remaining clusters in Auckland are well circumscribed. A brief period of ongoing level 4 restrictions would have allowed the Government to better understand both the extent of Delta outside of the Auckland region and the boundaries of the remaining clusters in Auckland. We believe the Government has taken a calculated risk in changing alert levels at this time. Time will tell whether this move has been a major mistake.

Michael Baker (MB): All of us appreciate how tough it is for Auckland being at level 4. However, moving out of level 4 does threaten the Government's current strategy. This strategy includes continuing with elimination - keeping Covid-19 out and stamping it out when we get cases and outbreaks - while we increase vaccine coverage, and then increase reconnection with the outside world. The Government should consider an urgent review of its current approach to identify additional measures to achieve Covid-19 elimination in Auckland. This process could include an expanded meeting of all of its advisory groups along with Māori and Pasifika community leaders from Auckland.

Michael Plank (MP): The move is a calculated risk and it remains to be seen whether it will pay off. Five weeks is a long time to be in lockdown and people are tired. But there is a danger level 3 could increase the amount of spread between household. A lot will depend on whether contact tracers are able to ringfence the outbreak and stop it spreading to new households over the next week.

How realistic is it that this outbreak can still be contained under alert level 3?

SW: It is still very realistic that we contain the outbreak at level 3 but it will require everyone to play their part. People must stick to their bubbles, work from home wherever possible, wear a mask, and get tested and isolate if they have symptoms.

SC: Currently the majority of transmissions is within households. Level 3 allows people to return to work and there are increases in services that people can access, such as takeaways or retail purchases. These changes open the potential for increased transmission beyond households. While it is very important that people stay in their bubbles, there is also the risk of increased transmission because of permitted increased contact between people outside of their households. This has the potential to make containment more difficult under level 3.

MB: Elimination is still possible at level 3 but will be difficult. At level 4 we have been seeing unexpected cases every day that indicate ongoing transmission in Auckland. Level 3 allows a great deal more mixing opportunities, particularly at construction sites, workplaces producing takeaway food, and the small number of schools that will open. Consequently, elimination will be much more difficult at level 3. The pattern of cases in Auckland suggests sustained transmission in marginalised groups that are probably quite disconnected from Covid-19 response measures.

MP: It is still possible we can eliminate this outbreak at level 3. But it will depend on people doing the right thing. Level 3 allows more businesses to open but it's absolutely crucial people stick to their bubbles and resist the temptation to meet up with family and friends because this is how the virus will continue to spread through the community.

What might be the consequences - for Auckland and the rest of New Zealand - of getting this call wrong?

SW: It's a calculated risk for us to move to level 3 now, so if it doesn't pay off then it will obviously be very demoralising for everyone. I have no doubt it will also be weaponised against us by those both here and overseas who are invested in our elimination response failing, so we should prepare ourselves for that.

SC: The most serious consequence is that we lose control of the virus which will lead to increased cases, hospitalisations, and deaths. Because of the inequities in vaccination delivery these consequences will be more severe for the Māori community. We will all spend more time in level 3 - and possibly level 4 - to prevent the health system being overwhelmed people with Covid-19. If the health system is overwhelmed by people with Covid-19 there is the potential for people with other illnesses such as heart attacks, strokes, serious injuries to have their care affected too.

Mahima Sen and Upashana Sen, of Sandringham cafe Elaichi, with freshly made muffins shortly after midnight as Auckland dropped to alert level 3. Photo / Hayden Woodward

MB: There are two outcomes at this stage: elimination, or continuing and probably increasing transmission. We will know in seven to 10 days which path this outbreak is likely to follow. Ultimately, where Auckland goes the rest of New Zealand is likely to follow. At level 3 in Auckland the most likely scenario will be increasing cases, eventually following the patterns seen in Victoria and New South Wales in Australia. Vaccine coverage rates in Auckland, and New Zealand generally, are still too low to fully protect public health. A rise in cases will result in more seriously ill people being admitted to hospitals, which will rapidly start to stretch available ICU beds and could exceed capacity. There would also be some deaths. This outbreak will almost certainly increase health inequalities. Māori and Pasifika have been most affected by the current outbreak. Their vaccine coverage is also lower than for European and Asian populations. This epidemic will therefore markedly increase health inequalities. To slow virus spread, Auckland may need to remain at level 3 for a prolonged period. We might also start to see more cases seeded to other parts of New Zealand resulting in them also needing level 3 restrictions. This response might need to continue until the end of 2021, depending on vaccine coverage and severity of the epidemic increase. As always, there will be an element of luck and we will need to take steps to minimise the risk of superspreading events for many months, unless elimination is achieved.

MP: We can see in New South Wales and Victoria how easy it is to lose control of a Delta outbreak. If this happened here it could rapidly stretch our health care systems and effectively consign us to level 3 restrictions for most of the rest of the year while we complete the vaccine roll out.

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If Auckland case numbers began tracking up again under level 3, would it prove too late to revert back to level 4?

SW: It will never be too late to revert back to level 4. It will be disappointing, but the alternative is far worse.

SC: No. However, this would have to be done very quickly. We have seen in New South Wales and Victoria that this virus can move very quickly, and it is very easy to lose control of it.

MB: A return to level 4 would be an option, but probably not the optimal or acceptable response. A better approach would be to work very intensively with the communities and areas where transmission is still occurring to achieve elimination.

MP: No. We need to keep a close eye on cases and, in particular, whether the virus is increasingly able to spread between households. If it does, we need to respond quickly and this could mean a move back to level 4.

Should this decision prompt the Government to go harder and faster on vaccination? What more can be done - and what can people do themselves to help things?

SW: I ask everyone that is vaccinated to have a conversation this week with their close friends and families about their decision to get vaccinated. We all need to reach out to those who still have questions about the vaccine to help them access the information they need to make an informed decision. We know there is a lot of misinformation spreading on social media which is targeting people's fears and so it's important that people understand how to spot misinformation and recognise when they are being manipulated by people who are trying to disrupt our vaccination drive.

Queues for the drive-through at McDonald's on Lincoln Rd shortly after 12:30pm, as Auckland drops to alert level 3. Photo / Hayden Woodward

SC: Yes, absolutely. Vaccination does prevent people becoming infected with Covid-19, and it is excellent at preventing hospitalisations and deaths if people do get sick with Covid-19 after they have been vaccinated. There are serious inequities in vaccination in the Māori community. The Government needs to provide more resources for Māori vaccination and ensure that vaccination is easily accessible to all whānau. More communication and information about the vaccination is required. It is important that this information/communication uses messaging and media that are relevant for different age groups. Whānau who haven't been vaccinated yet should do so. There are walk-in and drive-through clinics that don't need an appointment. You can also make appointments by phone and on the Covid-19 vaccination website. Whānau should also remember to wear a mask when outside, stay 2m away from people who aren't in your bubble, and wash hands a lot.

MB: The current Delta variant outbreak is a huge reminder of the importance of vaccination. The decision to move Auckland to level 3 should prompt rapid Government action to increase Covid-19 vaccination. Government should prioritise Auckland for vaccination and shift resources there to accelerate vaccine delivery. A key focus needs to be on raising vaccination rates for Māori and Pasifika. There should also be a focus on adjacent areas in Northland and the Waikato. The Government should rapidly consider making vaccination mandatory for those returning to work at levels 3 and 4. They included essential workers who have already returned to work at level 4, and workers in construction, retailing, food and beverages, and education who are returning to work at level 3. This mandate could be timed to come into effect within a week or so, giving these workers time to get their first vaccine dose or face not being allowed at work to help contain the current outbreak.

MP: There's no doubt that the more people get vaccinated, the easier it will become to control outbreaks like this, and the less threat there will be of our hospitals being overwhelmed. The sooner we can get people vaccinated the better, but it will take time to reach the really high vaccination rates we need, partly because of the gap between doses. In the meantime, people should get vaccinated as soon as possible and stick to their bubbles. Eliminating this outbreak is the fastest way to get out of lockdown.

Amanda Kvalsvig: There are two main ways to prevent viral spread. One is the alert level 3 and 4 approach of circuit breakers that keep people apart. This approach is highly effective. But as we've seen, circuit-breakers are disruptive and have the hardest impact on those who can least afford it. Unsurprisingly, people are asking for alternatives. The second approach is reducing transmission between people who are in contact. This approach is really the first prize. It keeps us connected to people, work, education and so on - all the things that make our lives meaningful and enjoyable. If we are to step away from circuit-breakers New Zealand needs to be much smarter about reducing transmission. That means bringing vaccines to those most at risk, getting to grips with indoor air quality, and getting comfortable with masks. We need an upgraded and highly focused alert level system that is equitable and built around the essential fact that the virus is transmitted through the air. So if we're stepping away from some tools in the toolbox, approaches to reduce transmission through the air are the ones we need to pick up fast. The new variants can outrun the contact tracing system very quickly if transmission through the air is not being actively reduced. The key point is that this virus is highly infectious but it's also very controllable. If we get this right we can continue to enjoy being out and about in our daily lives while keeping everyone safe.