A public health communication failure over the last six months:

General public understanding of the meanings of "under investigation," "close contact," and "community transmission." /1

When a case returns positive, investigation begins. The person involved is interviewed, their movements are obtained, and their close contacts (e.g., friends they've socialized with over the last 14 days, family members) are identified. /2

The people identified as "close contacts" are then tested, and ordered into isolation. From isolation, they pose minimal further risk to the community. Depending on the timeframes, they might not even be infectious yet. /3

So -- When there's an announcement of a new case which is a "close contact of an existing case," that's a good thing. It means contact tracing has been effective, and the chain of transmission has probably been interrupted. /4

A single case might cause several weeks of "close contact of an existing case" flow-on effects, because their friends and family members might have been infected, or might infect other friends and family members. But as long as they're isolated, that's *good*. /5

When that doesn't happen -- when a test is carried out, and there's no source related to someone who's already been identified -- that's community transmission. They're the cases we don't want, they're evidence that there are pools of disease festering in the community. /6

In all parts of Australia except Victoria, they're very rare. Almost all cases outside Victoria are being contact-traced to known sources, and are "close contacts" who are already in isolation at the time that the test was carried out -- That's why we've found them. /7

So when you see headlines today saying that another case has been confirmed in Newcastle who is a close contact of an existing case: That's good news. You have minimal risk from that one. That's the system working. /8

It's sad that we're 6 months into this and these concepts aren't well understood, that every new case is treated as if the sky is falling even if it's a close contact of a known case. I think there should have been better comms about this. There's no need for more anxiety. /9

One other point: Testing runs 24x7. Daily reports are a snapshot in time. If a positive test result occurs at (say) 10pm, and the statistics for the daily report are gathered at (say) 7am, the person who tested positive won't have been telephoned yet. /10

They'll show up in the stats as "unknown/under investigation." That doesn't mean "community transmission," it just means there hasn't been time to contact trace them yet. There'll be some of those every day. They'll mostly wash-out into other categories by the next day. /end