Te Pūnaha Matatini Covid-19 Data modeling expert Sean Handy says Auckland is working almost as well against Alert Level 4 Delta as it did last year.
He was describing some of the different models used to estimate the extent of population immunity and the spread of the virus. Health Select Committee this morning., And said the expected effective production for the current epidemic, or R, was now about 0.4.
“This is our average estimate at the moment. Obviously there is a certain amount of uncertainty about it. 0.4 is actually very good. The March-April epidemic was about 0.35 so Alert Alert Level 4 is almost as effective as Is working as it did last year. “
Professor Handy said reaching a stage of extinction – where the virus is no longer circulating in the community – would soon be possible if restrictions continue in Auckland.
“We’re still predicting a total of about 1,000 cases, and we’re starting to see an opportunity in the coming weeks, assuming we’re on alert level 4.
“You may remember me saying in the media, ‘I’m a little worried about Level 4 and we may need to strengthen it because of Delta … about what we’ve learned. I think our alert level 4 settings are actually effective in this epidemic and even though we are sitting on the outer edge of it, we are seeing an end. “
He said it was difficult to predict what New Zealand would be like without the lockdown, but it looked as if health care would be in place by this week.
Modeling estimates that vaccination rates could be halved by increasing the level of vaccination in 30 to 50 percent of the population.
“As you increase the rate of vaccination, the expiration time starts to decrease.”
He said it was important that current vaccination coverage not be considered independently of the impact of the current lockdown on the spread of the virus.
“While we’ve seen how well Alert Level 4 has done, we’ve done what we have in the presence of vaccine coverage, so I wouldn’t want to see them freely in two things.”
“In general, however, the higher our vaccination coverage, the more effective our alert level system will be.”
However, it was almost impossible to get immunity from the herd through vaccination alone.
“Theoretically it is possible if we get very high rates of vaccination in some optimistic scenarios but if you go to the disappointing aspect of the evidence and statistics it says that even 100% [vaccinated] Because of the effectiveness of the vaccine, you will still have to spread the word.
“There’s still a lot of uncertainty around that and the vaccine is being developed, but I think the weight of the evidence at the moment shows that with our current vaccine suite it’s not possible to get an exemption from the herd.”
There are other steps you can take to begin the process of preparation for mediation.
“You need some other control over space, and with these other controls you can get immunity from the herd – so with the use of massive masks, with certain types of social distance, with rapid testing. – You can talk about herd immunity, but not just vaccines.
“Then I think it’s important to point out that some of these things also need to be complied with.”
He said Delta was difficult to deal with – especially for workplaces and educational settings.
He said the understanding of hazards has improved a lot, but some changes can be made based on the science of aerosol transmission hazards compared to aerial and surface-based transmissions.
“I have constant concerns and I think we need to look at science as well as what to do in the interior in a practical way.
“We haven’t designed our interiors … to prevent respiratory viruses and we can do a lot there. In a hazardous environment and we don’t necessarily need to use masks in those high risk environments that work. There are places and education settings.
“I’d like to see a faster test. I mean, I think it’s a tool we didn’t take advantage of and I think we have to take advantage of it.”
“Regardless of the number of people being tested, it will give the authorities the confidence that the virus is being sealed,” he said.
“It’s hard for us to give difficult numbers. I guess I’d like to see an order for about 10,000 tests a day in the next few weeks.”
Handy said rapid antigen tests could be extremely useful next year as the country begins to move towards vaccination coverage and a strategy that can accept the increased risk of infected people coming into the country. ۔
“Intense antigen tests are not as sensitive as PCR tests … they don’t even pick up late cases in pieces, but the fact is that you can get these turnaround times very quickly, they can be really useful. . “
“Speed also means that, for example, they can be more effective for pre-departure testing,” he said.
“Also, because you can test frequently, you can make up for some of the sensitivity reduction by testing on a daily basis.”