Ministry of Health officials and public health experts on how high vaccination rates affect the response to Covid-19.
As the country gets closer to reopening its internal borders the Government has made it clear those who are vaccinated will be afforded the greatest freedom of movement.
Director-general of health Dr Ashley Bloomfield said today the reasons behind this were the much lower rates of transmission, severe outcomes and ability to pass the virus on to someone else from those double vaccinated with the Pfizer jab.
The Ministry of Health's own data had found from a group of 10,000 people, with 50 per cent vaccinated and unvaccinated, in the vaccinated group 375 people would become symptomatic, and just 13 need hospital care, Bloomfield said.
Of those unvaccinated, 2500 would be symptomatic, and 250 need hospital care.
Bloomfield said as vaccination levels rose the proportion of cases and those hospitalised who were vaccinated would rise too, but overall far fewer than if they were unvaccinated.
If 90 per cent of those 10,000 people were fully vaccinated, there would be 675 cases in total, requiring 23 hospitalisations. Among the 1000 unvaccinated there would be 500 cases, and 50 hospitalisations.
Bloomfield said people fully vaccinated were also 32 times less likely to die from Covid-19 than those unvaccinated, based on data from the United Kingdom.
Reduced transmissibility
Immunisation Advisory Centre director Professor Nikki Turner said over 1 billion doses of the Pfizer vaccine had been administered worldwide, in 148 countries. This meant there was "extensive data" about its safety and effectiveness.
International studies showed those who were fully vaccinated were also much less likely to pass the virus onto others who had no immunity.
Turner referred to a recent Swedish study of more than 800,000 families that found if one member of the household was already vaccinated or recovered from the virus, that reduced the spread to household members without immunity by about 45 to 61 per cent.
With two people immune, it increased to about 75-86 per cent, with three immune over 90 per cent, and with four people over 97 per cent.
While that study was not on the Delta variant, a recent Dutch study including Delta found a vaccinated person who caught Covid-19 had a roughly 63 per cent lower likelihood of passing on the disease to the household.
In terms of side-effects, Turner said even with myocarditis, which can cause fatal reactions, people were four times more likely to develop it from Covid-19 than the vaccine itself.
Bloomfield said this time last year achieving 70 per cent vaccination levels was deemed a benchmark, but that was prior to Delta.
The 90 per cent vaccination milestone was "higher than what we would have imagined", Bloomfield said. But it was not a target, rather a milestone.
Bloomfield said that 90 per cent of 12-plus age groups was about 76 per cent of the total population. He said provided MedSafe gave approval the rollout for those aged 5 to 11 would start in the first quarter of next year.
There was a "relatively small study, 2000 to 3000 kids" at the moment for the age group, but New Zealand would be able to look at how it is rolled out in the US.
Equity issues
While the 90 per cent across DHBs was set into the new Covid Protection Framework, Bloomfield said the framework also offered other levels of protections for vulnerable communities.
As of Monday, 81.1 per cent of the eligible population - aged over 11 - have been fully vaccinated against Covid-19, and over 90 per cent at least one dose.
Of the Māori population, just 61 per cent are fully vaccinated, and 77 per cent received at least one dose.
Asked why the Government was comfortable allowing people who could have Covid-19 to travel around the country when these huge inequities persisted, Bloomfield said the new framework would recognise these.
In preparing advice for people travelling around the country Bloomfield said it would take into account vaccination rates, the vulnerabilities of local populations and health resources.
Ministry general manager for equity in the vaccine rollout Tamati Shepherd-Wipiiti said while Māori rates were trailing behind there had been a big surge in recent months since the rollout opened up to younger age groups.
Before Super Saturday, Māori daily vaccinations averaged about 2000 to 3000, and that had since increased to about 5000 a day.
Māori and Pacific providers like Te Puea Winiata and Silau at South Seas were working closely together to address the vaccine challenge and many Pākehā were also preferring these health providers, he said.
Bloomfield said with modelling showing up to 200 cases a day on average by the end of the month, there could be several thousand Māori who have been infected by the end of the outbreak.
Shepherd-Wipiiti said there were much more door-to-door initiatives occurring and partnerships between iwi, health providers and DHBs.
"We've worked in partnership with iwi, in particular through our data sovereignty group to help iwi access their own data. They've got the toolset ready, if the iwi need a user ID they're ready to go."
Bloomfield said data will be shared with the Whānau Ora Commissioning Agency.
After discussions it has already occurred in Tāmaki Makaurau and Kirikiriroa, as well as with the agency's providers on the ground and with iwi in Waikato, and would continue.
