Bloomfield gave evidence that super-spreading events have played a significant role in
the spread of the virus in New Zealand. For example, the Omicron outbreak was initially
fuelled by two main events, the SoundSplash festival and a large wedding.
• [175] Gatherings that have the highest risk are those where there are large numbers of
people, which continue for a long period of time, and where there is close interaction
between attendees. Key risk factors include the number of people, their proximity, the
length of time they are together, people attending from outside the region, ventilation
and presence of vulnerable people.
• [176] The evidence from both Dr Town and Dr Bloomfield is that faith-based gatherings
are high-risk settings. Activities commonly occurring in faith-based gatherings such as
singing, close personal contact by hand shaking, hugging and laying on of hands,
administering and receiving communion, and sharing food and drink, are high risk
activities and increase the likelihood of a super-spreading event. In addition, faith-based
gatherings are very likely to have vulnerable people in attendance, including older
people and Māori and Pasifika communities, who are at risk of severe outcomes from
Covid-19.
• [177] Both Dr Town and Dr Bloomfield gave as an example the August 2021 Delta
outbreak where a South Auckland church was at the centre of the largest cluster. This
was an example of the high-risk nature of faith-based gatherings. They also refer to a
large cluster related to an outbreak at the Shincheonji Church in South Korea, at the
start of the pandemic, that resulted in over five thousand cases. The applicants disputed
the similarity and relevance of the South Korean example.
• [178] The data from the Delta outbreak from early August until 11 October 2021 was
analysed by Ministry of Health officials, with a view to determining the settings with the
highest secondary attack rate (SAR). The SAR is the percentage of contacts of an index
case that become a secondary case. Dr Town’s evidence is that it can be a more
useful measure of transmission risk than the reproduction number, which is
heavily dependent on the number of contacts.
65
• [179] The first Delta SAR Analysis, which detailed 1,051 secondary cases among the
41,440 contacts identified, found that households gave rise to the majority of secondary
cases and have the highest SAR, with 45.6 per cent. The next highest SAR was for private
gatherings, with a SAR of 10.4 per cent. The significance of that data is disputed by
Professor Flanigan, on the basis that it only evidences 72 secondary cases arising from
private gatherings, with no distinction made between faith-based gatherings and others.
• [180] Dr Town’s response is that this misunderstands the nature of super-spreading
events and the risk they pose. As he explained, super-spreading events occur when an
individual, or a small number of individuals, cause a substantial number of secondary
cases, with the size of the cluster amplifying through successive chains of transmission.
Individuals at a super-spreading event who contract the virus will go on to pass it on to
family members and others, seeding the virus throughout the community. Dr Town
provides an analysis of genomes sequenced in the period from 4 August 2021 and
broadly representative of the proportion of the cases arising from different clusters in
the Delta outbreak. While faith-based gatherings were not captured as a discrete variable
in the dataset in Delta Outbreak SAR Analysis, the cases arising from the South
Auckland church cluster are graphically represented.
• [181] Professor Flanigan disputes the relevance of the Delta Outbreak SAR Analysis on
the basis that general public health measures such as masking and physical distancing
were not in place at that stage (in Alert Level 1), so the data does not reflect the impact of
such measures on transmission. However the respondents note that no such restrictions
were in place across the board at Alert Level 1 and, prior to discovery of Delta in the
community, social and other activities were taking place without restriction. In that
context, the fact that the super-spreading event resulting in the spread of Delta
throughout the community occurred at a faith-based gathering illustrates the high-risk
nature of faith-based gatherings, compared to other activities.