Young main target of Delta

The number of sub-clusters not yet epidemiologically linked to the Delta community Covid-19 outbreak is now greater than the number of linked sub-clusters.

There have been four new unlinked sub-clusters announced this week alone – two reported on Thursday.

Taking a deep dive into where these sub-clusters are and who is caught up in them reveals the Delta outbreak has made its way into every corner of Auckland, and has largely affected younger people.

Here’s what we know about the 24 subclusters linked in the Delta community outbreak.

Ministry of Health data shows as of yesterday, nine are considered dormant, 10 are contained, and five are active.

The majority of the active sub-clusters (three of the five) do not yet have epidemiological links to the outbreak. These are clusters where there have been cases reported in the previous 14 days and are not household or other known contacts of previous cases.

Nine sub-clusters have had new cases linked to them in the past five days, and eight have not had any new cases in 14 or more days.

To date, seven sub-clusters overall have had fewer than nine cases.

What we know about the linked sub-clusters

The biggest linked sub-cluster remains the group associated with Assembly of God church in Ma¯ngere, with 386 cases.

The ‘‘Ma¯ngere church secondary transmission’’ sub-cluster had 168 cases linked to it at last count.

The third-biggest sub-cluster, with 80 cases, is known as the Birkdale social cluster. This group includes Case A and other contacts on Auckland’s North Shore.

We know one of the epidemiologically linked sub-clusters is associated with Auckland University of Technology (AUT), and another was previously referred to as ‘Massey households and workplaces’.

As of Thursday, there were two active epidemiologically linked sub-clusters. One, centred around the Howick ward, had 29 cases linked to it, with a median age of 20-24. The other, in the Manukau ward area, had 12 confirmed cases. The median age was 25-29.

A larger sized-sub cluster, with 59 cases, sprung up in the Waita¯kere ward, and had a median age range of 20-24. This was deemed contained. There were two other linked sub-clusters in the Waita¯kere region with 40 and 16 cases, each with a median age range of 20-24. These subclusters were dormant and contained, respectively. Another, now dormant, linked sub-cluster was detected in the Rodney ward and had 12 cases, with a median age of 25-29.

What we know about the unlinked sub-clusters

The unlinked clusters have a genomic link to the current community outbreak – which means officials know they are connected somehow – but are yet to be linked to a known case or exposure event.

There are currently four active unlinked sub-clusters. These range in size from between 0-9 cases (the actual number has not been released to protect people’s privacy) to 18 cases, to 78.

This means there are more active unlinked sub-clusters at the moment than active linked sub-clusters.

Both the 18 and 78-case sub-clusters are in the Manukau ward area. The locations of the two smaller unlinked sub-clusters, each with fewer than nine cases, have not been disclosed.

Those who make up the 78-case subcluster – the fourth largest in the outbreak – have a median age of 15 to 19.

As of 9am on Thursday, three of the four active unlinked sub-clusters had a new positive case reported in the last day.

A 20-case unlinked sub-cluster in the Manurewa-Papatoetoe ward area, considered contained, had a median age of just 10-14. Another sub-cluster with 19 cases in the Manukau ward, with a median age of 20-24, was also contained. And a 12-case sub-cluster in the same ward, among the same age range, was now dormant. An 18-case sub-cluster in the Waita¯kere area – also dormant – bucked the trend slightly, as the median age was 45-49.

There were a further four smaller unlinked clusters (each with fewer than nine cases) that were also dormant [no new cases in more than 14 days]. Two were just two days off being deemed ‘‘closed’’ – marking 28 days since a new case was reported.