‘Very high’ vaccination rate needed to end lockdowns – Expert Reaction

A new modelling paper says that New Zealand may no longer need lockdowns if we vaccinate 90 per cent of the population.

The paper authors say moderate public health measures like mask use and gathering restrictions may even have to remain at this high rate of vaccination, due to how transmissible the Delta variant is.

See the Te Pūnaha Matatini paper and press release here. Note: this paper has not been externally peer-reviewed.

The SMC asked experts to comment on the paper.

Dr Dianne Sika-Paotonu, Immunologist, Associate Dean (Pacific), Head of University of Otago Wellington Pacific Office, and Senior Lecturer, Pathology & Molecular Medicine, University of Otago Wellington, comments:

“The modelling work undertaken by Te Pūnaha Matatini demonstrates that very high vaccination rates combined together with associated public health measures will be needed to protect against the Delta variant of the SARS-CoV-2 virus – population immunity will be reliant upon both these approaches.

“The current COVID-19 outbreak involves the Delta version of the virus, which is more dangerous within the community setting and is highly infectious, easily transmissible and more likely to cause severe illness – we’ve all seen how a single case of Delta very quickly turned into many more. With Delta still in our communities and just over one third of the population in Aotearoa New Zealand fully vaccinated, it is critical that those who haven’t had the vaccine yet are vaccinated as soon as possible, but also that testing, monitoring, mask wearing and vaccination efforts continue moving forward.

“This modelling work also indicates that vaccination rates of at least 90%, together with sustainable public health measures would reduce serious illness and deaths – vaccine coverage would need to reach across age groups, geographic locations, communities and ethnicities within Aotearoa New Zealand. As has already been demonstrated, our Māori and Pacific communities remain highly vulnerable to being disproportionately affected by COVID-19, and will likely bear the heavy burden and toll of any further outbreaks.

“The 12-15 year old age group is the most recent cohort to be added to the vaccination programme, and if the Pfizer–BioNTech COVID-19 vaccine is approved for use in children aged 5-11 years, both these young groups must be supported to get vaccinated – the most recent Delta outbreak in Aotearoa New Zealand involved 13 babies (under the age of 1), and 253 children aged under 12 years.

“Ultimately, vaccination levels within Aotearoa New Zealand must increase to keep everyone safe from COVID-19 – including our most vulnerable. High vaccination rates of 90% and beyond coupled with the appropriate public health steps, could potentially help avoid future higher alert level lockdown measures.”

No conflict of interest declared.

Dr Rachelle Binny, Mathematical Modeller, Manaaki Whenua – Landcare Research; and Principal Investigator, Te Pūnaha Matatini, comments:

“These results show the importance of New Zealanders achieving the highest vaccination coverage we possibly can. If nearly every New Zealander gets the vaccine, we could avoid the need for strict Alert Level 3-4 restrictions to control future Delta outbreaks. Instead, the spread of the virus could be managed with an effective contact tracing and quarantine system and more moderate public health measures in place, like wearing face masks and limiting the size of indoor gatherings. We’d have a better chance of keeping schools and workplaces open while the virus is in the community, and still be able to meet up with our vaccinated friends and whānau.

“The alternative is bleak. Failing to reach these high levels of vaccination mean we will need to keep relying on lockdowns and tight border restrictions to avoid the thousands of COVID-19 fatalities that would arise if Delta was in the community. These high fatality rates could cripple our healthcare system, and Māori and Pacific communities – who have a higher risk of hospitalisation and fatality from COVID-19 – would bear the brunt of this health burden.”

Conflict of interest statement: “I am a member of Te Pūnaha Matatini’s COVID-19 research team, along with the authors of this study, and am partly funded by MBIE for research on mathematical modelling of COVID-19.”

Associate Professor Alex James, School of Mathematics and Statistics, University of Canterbury, comments:

“This work presents the absolute worst-case scenario of what could happen when we reach our final vaccination coverage. The doom and gloom presented here assumes a return to the full comforts of Level 1 with only minimal reductions in transmission due to contact tracing. It’s also unclear whether children spread the virus like adults do and this can have a huge effect on outcomes.

“It’s possible to take a more optimistic approach, in particular looking at countries like Denmark that have more realistic and achievable levels of vaccination. Some reasonable precautions like sensible use of masks and good ventilation could significantly reduce spread but still allow businesses including tourism to operate, schools to be open and for people to socialise while keeping case numbers low. This would give time for the risks and benefits of vaccinating children to be considered.

“It’s a no-brainer that we want as many eligible people to be vaccinated as possible but it will take a lot of consideration before we can widen our eligibility criteria.”

No conflict of interest declared.

Professor John Hopkins, Professor of Law specialising in Law and Disasters, University of Canterbury, comments:

“This is not a surprise. The evidence from Singapore seems to be showing that even high vaccination rates will still result in significant hospitalisations (including ICU) without continued social restrictions. Even there, where vaccination rates are over 80% of the total population, continued social restrictions (equivalent to our L2) have not stopped a rapid rise in cases and concerning levels of hospitalisation, in wake of an easing of border restrictions. Given that one of New Zealand’s key vulnerabilities remains its chronically underfunded health sector and its lack of ICU capacity it is difficult to see how, even with high levels of vaccination, hospitalisations will be kept at a manageable level without significant and ongoing legal restrictions around social interactions, once border restrictions ease. The fact that the penalties for breaching those restrictions have recently been increased suggests that government is very well aware of this.

“Singapore is still driving up vaccination rates, as life for the un-vaccinated becomes increasingly awkward (with regular testing as the alternative if they wish to socialise). Such policies may be difficult to enforce in New Zealand but the alternative may be strict social restrictions for a long period of time, something that is equally unpalatable to most. Thus the choice may to discriminate against the un-vaccinated, impose strict social restrictions upon the whole population (for the long term) or accept that our vulnerable health system will risk being overwhelmed.”

No conflict of interest declared.

Associate Professor Siouxsie Wiles, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, comments: 

“The new modelling work from Te Pūnaha Matatini supports what we’ve been seeing overseas in that very high vaccination rates are needed throughout the population, including in younger children, to keep hospitals from being overwhelmed by people suffering from COVID-19. It has been distressing to see the reports of paediatric intensive care units in the USA filling with sick children because they cannot yet be vaccinated. The good news is that vaccine trials in children are currently underway. There is no reason to suspect there won’t be a safe and effective vaccine available for children sometime next year.

“The data clearly shows that we will need everyone who can be vaccinated to be vaccinated if we want to manage the pandemic and any outbreaks without needing to use alert levels 3 and 4. Yet we know that there people creating and sharing false and distressing misinformation about vaccines that is making people question whether they want to be vaccinated. The research shows that we are influenced most be people who we love and care for. That means all of us need to reach out to our families and friends, to show empathy and understanding of their distress, and to make sure they have access to the correct information about the safety and effectiveness of vaccines.”

No conflict of interest declared.

Professor Nikki Turner, Director Immunisation Advisory Centre, University of Auckland, comments:

“The pictures painted from the modelling don’t come as a surprise and serve as really useful context to help us all understand why it is so important as many of us as possible get vaccinated.

“Whether we do or don’t manage to contain community spread of COVID-19, the only good answer to ensure our health services will be able to cope is to achieve a really high vaccination rate. Simply, the higher the vaccination rate, the fewer the number of people who will end up in hospitals or dying of COVID-19.

“I would like to give a shout out to the health providers and vaccination clinics right around the country who are reaching out in all sorts of ways to support our united goal to get as many people vaccinated as possible. We are making excellent progress.”

No conflict of interest declared.

Dr Rawiri McKree Jansen (Ngati Raukawa, Ngati Hinerangi), Clinical Director, National Hauora Coalition, comments:

“I agree that very high vaccination rates are required to avoid significant hospitalisations and deaths. Very high vaccination rates are achievable – evidenced by some providers (Maori, Pacific and mainstream) achieving childhood immunisations rates higher than 90%. This likely requires of us (health system and health providers) to be deliberate, dedicated and relentless. The benefits to our communities and Aotearoa are obvious.”

No conflict of interest declared.

Dr Matthew Parry, Senior Lecturer, Dept of Mathematics & Statistics, University of Otago; and Principal Investigator, Te Pūnaha Matatini, comments: 

“The results of the paper are in broad agreement with modelling that has been carried out in other countries. The high levels of vaccination plus continued public health measures that are needed to achieve population immunity are another reflection of the way Delta has moved the goalposts on us. I hope the paper will serve to spur the vaccination drive in NZ; it also reminds us of the importance of achieving equitable vaccine coverage.”

Conflict of interest statement: “I am a member of Te Pūnaha Matatini’s COVID-19 research team, along with the authors of this study, and am partly funded by MBIE for research on mathematical modelling of COVID-19.”

Dr Jagadish Thaker, Senior Lecturer, School of Communication, Journalism & Marketing – Te Pou Aro Korero, Massey University:

“The paper highlights that all our efforts should be to achieve an overall vaccination rate higher than 90%, particularly within our at-risk communities where there has been a persisting vaccination gap: About 52 percent of eligible Māori and 67% of eligible Pacific Peoples have received their first dose compared to over 76% European NZ (and 75% overall rate).

“While public willingness to get a vaccine is high (about 67% among Māori yet to get a vaccine want to get one, according to most recent July-August Ministry funded survey), the vaccination gap points to the need to improve vaccine access. Our at-risk communities are already facing a disproportionate burden. They shouldn’t suffer inequities in vaccine access and their ability to follow other public health safety measures, which the paper highlights will be needed.

“From a public health communication perspective, we need to emphasise the need to follow other COVID-19 safety measures, even after vaccination, to ensure we succeed in our elimination strategy, or at least a strategy where we see no Covid-19 deaths.”

No conflict of interest declared.

Professor Emeritus Innes Asher, Department of Paediatrics: Child and Youth Health, Faculty of Medical and Health Sciences, comments:

“The vaccine modelling is aspirationally useful if Aotearoa were a country people where all people were living in ideal circumstances and none struggled to feed or house themselves or access health care. But nothing could be further from the truth. Child Poverty Action Group, reporting on the first year of the pandemic demonstrated, especially for children and young people, dire outcomes.”

Note: Professor Asher is a children’s health spokesperson for Child Poverty Action Group.