There is now a 95% chance COVID-19 has been eliminated in New Zealand, according to, based on official Ministry of Health data.
As of June 4, New سԹhas had 20 consecutive days of zero new cases, with only one active case remaining. The last new reported case of COVID-19 was on May 15 (going by the date the case was first suspected rather than later confirmed).
This still leaves a small chance of undetected cases, and we know that COVID-19 is passed on at.
New سԹis now preparing to relax itsto alert level 1 from as early as next Wednesday, which would end physical distancing and size restrictions on gatherings. But our modelling suggests removing limits on large gatherings will increase the risk of a very large new outbreak from 3% to 8%.
To reduce this risk, New Zealanders will need to continue avoiding theof possible infection: closed spaces, crowded places and close contact.
As crowds return, the risks will rise
New سԹis now very close to its elimination target. But there is still a 5% chance of undetected cases.
On June 3, Prime Minister Jacinda Ardernof the impending alert level 1 rules. Border closures will largely remain (except for returning New Zealanders) but all other significant restrictions on people’s movement within New سԹwill end.
From the perspective of the virus, the most significant change will be the end of restrictions on the size of gatherings. Airlines can fill up economy class again, nightclubs can pack their dancefloors and universities can open their lecture theatres.
Someone who caught the virus three or four weeks ago may not have developed severe symptoms (which happens in) and not got a test. They could have passed the virus on to someone else, who also missed out on a test.
A chain of infections like this could continue for a while before it is detected. Some segments of the population, such as younger people, areand are therefore more likely to sustain hidden infection chains.
COVID-19 is a. The reproduction number (R0) tells us that. But for every ten people who catch COVID-19, nine probably won’t pass it on, while the tenth person may turn up at an event and infect 25 others.
Risk from returning travellers
There is also a chance COVID-19 could enter New سԹwith an international traveller. Last week, around 200 people, almost all returning Kiwis, touched down in New سԹevery day.
Many came from places like Australia, Hong Kong or Tonga – all countries relatively free of COVID-19. Some also arrived from the USA, where the. Between February and April, we know that between 0.1% and 0.2% of all arrivals tested positive. With these numbers, we should expect one or two new cases to arrive each week.
New arrivals must remain in. The incubation period for COVID-19 is usuallyand it is rare for symptoms to begin more than 14 days after being exposed.
The bigger risk is a symptom-free person arriving and passing the virus onto someone at the same quarantine hotel, who then leaves before their symptoms appear.
Ministry of Health data show eight of New Zealand’s 500 imported cases developed their first symptoms more than two weeks after arriving. Maybe they caught it before they arrived or maybe they caught it during quarantine. Either way, they would have been infectious after they left quarantine.
People who work at the border – airline cabin crew, biosecurity or immigration personnel and staff at quarantine hotels – are at similar risk.
The inevitable new case
show the risk of new cases coming from within New سԹis now comparable to that from international travellers. The risk from international arrivals stays about the same whether we’re at level 1 or 2, while the risk of domestic transmission is decreasing.
The most important question is how we will cope when the inevitable new case arrives.
Each active case is like a small spark waiting to start a fire.tells us most of those sparks go out, but a small number will ignite. These sparks are the problem: it could be an infected person at a choir rehearsal, at a nightclub, or cheering for their sports team.
New سԹis fortunate to have highly trained, experienced contact tracers standing by. But they need our help. If you were to test positive, could you remember everywhere you have been for the last week and who else was there? A contact tracer’s nightmare is a large gathering with no record of who attended.
To move to level 1, we first need to ensure our contact tracing systems, including the, QR codes and sign-in sheets at shops, are up to scratch. We need to be confident we can manage the risks when hundreds of people gather or attend protest marches. We have to be able to do these things safely while COVID-19 is still out there.
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