Covid 19 Omicron outbreak: Wastewater tests suggest peak of wave has passed

Wastewater tests suggest the South has passed the peak of the current Omicron wave of Covid-19, but also confirm that cases in Otago and Southland remain substantially under-reported.

Data from the Institute of Environmental Science and Research shows that the amount of Covid-19 virus shed into the wastewater system has been steadily dropping at almost every testing site in the South.

Bluff, where viral loads are rising, and Queenstown, where they have remained static, were the exceptions among the 11 locations tracked by ESR.

However, one constant at all sites was that the amount of Covid-19 detected in the wastewater system was still tracking well above the actual number of cases being reported to the Ministry of Health - in sites such as Green Island, Mosgiel, Cromwell, Alexandra and Wanaka significantly so.

Yesterday, a further 541 community cases of Covid-19 were reported in the South, a low figure which reflected the usual low number of test results reported over a weekend.

However, that was 153 cases down from the previous Monday, and meant the rolling seven-day average of cases up until yesterday was 730. At the corresponding time the previous week the southern rolling average of cases was 849.

The deaths of a further three southerners who had Covid-19 were reported yesterday, which took the southern toll for the pandemic to 160.

Positive results from wastewater testing at Queenstown reveal cases of Omicron remain steady. Photo / George Heard, File

Nationally, there were 24 new deaths reported, which the Ministry of Health said took the total number of publicly reported deaths with Covid-19 to 2006.

Although southern case numbers are slowly dropping, the local health system remains under serious stress.

Yesterday, there were 41 people in southern hospitals who had Covid-19, a sharp jump up from the 24 cases reported on Sunday.

Prime Minister Jacinda Ardern said the Government would monitor hospitalisation rates over the next fortnight, as they tended to spike several days after a peak in case numbers.

She also confirmed that nationally wastewater testing rates were trending down but said case numbers would need to be monitored closely, especially as the school holiday break might have slowed the spread of Covid-19.

"But maybe, maybe, we may be seeing a decline in cases."