Auckland University immunologist Dr Anna Brooks says New Zealand is facing a huge number of long Covid cases in the aftermath of Omicron.
There have been 275 new cases of Covid-19 reported in Te Tauihu (the top of the south) on Monday.
In its daily release of data, the Ministry of Health reported 6638 new cases nationally, with 480 people in hospital, including 12 in ICU.
There were seven further deaths reported: three from Auckland; one from Waikato; one from Bay of Plenty; one from Wairarapa and one from Canterbury.
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In Nelson-Marlborough, there were eight people in hospital on Monday.
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It comes after the region reported 222 new cases on Sunday and 287 on Saturday, following a decreasing trend in the region over the past few days.
The region now has 2011 active cases, with 23,470 recovered. There have been 11 deaths.
Cases peaked in the region in March, but the long tail of Omicron is continuing to impact on hospital workloads and staff.
Nationally, there are 52,860 active cases. The seven-day rolling average for new cases was 7553 on Monday, down from 8355 last week.
Nelson Marlborough Health, which uses different reporting times to the Ministry, reported 280 new cases on Monday.
Of those, Nelson had 97, Richmond 38, Motueka/Moutere 19, Golden Bay six, Tasman other 17, Blenheim 82, Picton 10, Marlborough other seven, unknown/other region four.