- A study has found that test and trace has stopped only six percent of cases of covid
- But it warned the figure based on high self-isolation compliance, if it was not in place.
- The system prevented 14 million people from self-isolating unnecessarily
As per official estimates, the test and trace system of No10 has barely had any effect in thwarting the spread of COVID.
The controversial £37bn plan over the past year has been heavily criticized for being ineffective at breaking the chains of transmission.
New government modeling found the program – which critics have described as the biggest waste of taxpayer money – may have reduced cases by only six percent.
It also estimates that people in isolation prevented 1.2 million to 2 million secondary cases, of which NHS Test and Trace is responsible for preventing 300,000 to 500,000.
It is estimated that people with COVID symptoms and their homes would still be isolated if testing was not offered.
But health chiefs noted that without the test being offered, millions more people would have unnecessarily self-isolated if not infected because they could not prove they were negative through a swab.
According to official figures, Test and Trace identified nearly 900,000 positive cases in August.
It comes as Boris Johnson will warn today that the pandemic is ‘not over’ as he reveals his ‘winter plan’, acknowledging that another lockdown cannot be ruled out entirely.
This figure shows that more than a quarter of the transmission of Covid occurs in the first four days after catching the virus, while 73 percent of transmission occurs after four days.
The graph shows the proportion of reduced COVID cases in different groups, such as positive PCR cases (blue and light blue) and their household contacts (red). The dotted line shows how many of these cases could have been prevented in a hypothetical scenario where people who developed symptoms and their families were isolated. Anything above that line had the added effect of NHS Test and Trace
The gray line shows the ratio of transmission reduction from the NHS test trace and isolate. The blue line on the left graph shows how much transmission would be reduced without the testing system if people and their families stayed home when they had symptoms.
The graph displays estimates of the R rate without testing and tracing (red line) if the virus was able to spread freely; The rate if there was no testing but people followed the isolation rules when they experienced symptoms (grey line) and the R rate was actually recorded (blue line). The solid black line shows a decrease in the R rate due to test and tracing, while the dotted black line indicates a direct effect of NHS test and trace.
The graph shows the number of people who would have been isolated at home if there was no NHS Test and Trace in place. The testing system estimates that it prevented unnecessarily isolating 14 million people between last August and April who were identified as not having been infected through testing. The dark blue part of the graph shows the confirmed COVID cases that will be isolated without test and trace, compared to those who are not infected (light blue) and household contacts (red).
a report good Published by NHS Test and Trace, it looked at the impact it had if people with symptoms were still isolated without access to testing.
It did this by analyzing the reduction in transmission from testing, tracing and isolation from the current plan.
This was then compared to a hypothetical scenario where testing was not offered and households are asked to self-isolate if someone develops symptoms of COVID.
A panel including ‘Professor Lockdown’ Neil Ferguson, an epidemiologist at Imperial College London, helped with the modeling.
The study, which looked at the period from last August to April, found that the test and trace scheme reduced transmission by between 10 and 28 percent.
Will Boris’s winter plan be enough to avoid the lockdown?
Boris Johnson will warn today that the pandemic is ‘far from over’ as he reveals his ‘winter plan’ – acknowledging that another lockdown cannot be ruled out completely.
The PM is set to lay out his strategy at a press conference this afternoon, after Health Secretary Sajid Javid gave the outline to MPs in a statement.
He will stress that vaccines can be the main defense against the disease, with boosters for over 50s and jabs for under-16s starting soon.
But the blueprint includes a return to mandatory masks, working from home and some social distancing if the NHS is at risk. Vaccine passports will still be an option, even though they won’t originally be offered in England from next month.
And Health Minister Nadim Jahvi said this morning that a lockdown is on the table as a ‘last resort’ if infections get completely out of control.
Scientists are already warning that the country is heading into a winter with higher levels of cases, saying it ‘doesn’t bode well’ for hopes of avoiding further restrictions.
But if people stayed home when they suspected they had the virus anyway, as they were supposed to, the testing system only reduced transmission by six to 19 percent.
However, the report claimed that the T&T system was ‘significant’ in reducing the R rate – a measure of how fast the virus is spreading – and bringing it down to one.
It asked 11 million people to isolate during the study period.
However, the report cautions that the data gives a ‘very high-level view of the impact of the whole system’, so it should not be used to evaluate its specific components.
And it notes that testing and contact tracing may have prevented outbreaks in other settings, such as from hospitals, which were not included in the figures.
It also warned that ‘it is extremely difficult to predict how people will actually behave’.