12% increase in people getting tested which is good (now 1.74m in a week(!)), but note from 6th Nov, pillar 2 now includes people having the rapid lateral flow tests (e.g. Liverpool pilot) and this will only increase in numbers.
The knock-on impact is lower P2 positivity rates.
The implications of this is that it makes it far harder to interpret positivity rates, esp if you don't separate out test device, or asymptomatic vs symptomatic testing.
Cases up 11% in the week to 167,369, increases across both P1 and P2.
Case variation by age and region, including impact on hospitalisations and deaths covered here:
After two weeks of improvements in turnaround times, they've stalled this week (note, rapid lateral flow tests not included in turnaround times).
As has contact tracing performance.
There were 133,195 cases reached - 85%, which is the same proportion as the week before (although this is high relative to most of the time since T&T launched)
And of these cases, 3,613 were part of outbreaks in high risk areas and therefore managed by PHE health protections teams, 10% fewer than week before, and 129,582 were managed by the T&T call handlers or local contact tracing systems.
And the proportion of cases providing details of contacts also has settled at around 82%
Despite a 10% in the number of cases reached, there was fall of 1% in the number of contacts identified - 313,771.
This is because contacts per case dropped for cases not handled by HPTs to just 2.3 (down from 2.6). The wk on wk fall for cases handled by HPTs stopped (is 3.4)
And again another example of where T&T is really struggling to improve is percentage of contact reached. Still 99% for cases handled by HPTs, and languishing at 59% for all the other cases.
This means that overall, optimistically just 51% of contacts of known cases are likely to be reach (85% of contacts reached, and 61% of contacts, assuming those who say they don't have contacts really don't).
This is still far from what's needed to really make a dent on spread.
It also means over 23k known cases and 123k known contacts not reached.
Not to mention cases not tested, contacts not shared with T&T, and the proportion of people who actually go on to isolate.
The data by local authority was updated this wk to record location of cases & contacts based on where the test was rather than GP is registered.
Despite this there's huge variation by local authority (20%+) with significant unquantified potential impact on inequalities.
And finally, timeliness of contact tracing again stalled after two weeks of improvements. With 73% of cases reached within 24hrs, and 45% of contacts.
As ever, we still don't have data on the relative contribution of local authority contact tracing systems, and it would be so useful to know how they're contributing to the overall system performance.
In general, it's a much better T&T picture than three weeks ago, but for contact tracing, there still a long way to go.
Changes are def being made across the system and fingers crossed they help as we head towards December.
Latest PHE flu & COVID surveillance report, up to 15th Nov.
- ⬆️Case rates in over 70yrs.
- ⬆️hospitalisations, ICU admissions & deaths.
- Big variation by region, ethnicity, age, and deprivation.
- (+ some good news on flu & flu jabs)
Confirmed cases of COVID plateaued this week, and positivity rates dropping.
Still probably a little early to see results of 6th Nov restrictions, but local restrictions likely important. And new use of lateral flow tests (pillar 2) may be contributing to lower positivity rates.
And case rates falling across most aged but crucially NOT among age 70yrs+
Irrespective of the fact that 50,000 of 5,000,000 is 1% rather than 0.1%, here's a v short selection of data that might help to clarify some of the differences between flu and COVID-19.
Lots happened during this week
- schools back after half term
- Liverpool's mass testing started on 6th Nov
- national restrictions (second lockdown-ish) started 5th Nov
Number of cases continued to rise, but overall positivity dipped for the first time suggesting more testing now being done.
As mass testing starts, gets increasingly important to separate asymptomatic from symptomatic testing.
One thing missing is positive predictive and negative predictive values (PPV and NPV) that crucially depend on what proportion of people being tested have disease - the prevalence.
Take recent ONS survey - 1.1% of pop infected: PPV is 73%, meaning around 1 in 4 positive tests are false positives
(NPV is 99.7% - if you test -ve, you are)
Test 1000 people: there will be 8 true positives, 3 false positives, 3 false negatives, and 986 true negatives.
If in NW where prevalence is 2.2%, PPV rises to 84% (about 1 in 6 positive tests are false)
BUT in SE, prevalence is 0.5% meaning PPV is 55%, i.e. every other positive result is a false positive.