'UK's test and trace system having marginal impact and must grow at same rate as virus'

London: The UK government's test-and-trace system is only having a "marginal impact" on the spread of Coronavirus, scientists advising ministers on the pandemic have warned in a damning assessment of the multi-billion pound programme, The Independent reported on Tuesday.

Despite previously being described as "world-beating" by Boris Johnson, the top experts also warned the impact of test-and-trace will "further decline" unless it grows at the same rate as the epidemic.

The alarming evaluation of the system forms part of the latest documents released from the government's Scientific Advisory Group for Emergencies (Sage) after British Prime Minister's Covid-19 briefing on Monday evening.

Among the published minutes, the body also urged ministers to consider the immediate introduction of a two-week 'circuit breaker' lockdown, including the closure of pubs, bars and restaurants and banning households mixing.

The details emerged on the same day Johnson warned that rising cases and hospital admissions are flashing like "dashboard warnings in a passenger jet" as he set out the new three-tier system for England – considerably short of Sage's recommendations.

In a paper released on Monday evening the body, which is attended by observers from No 10, said an effective test, trace and isolate system is "important to reduce the incidence of infections in the community".

However, of the current system, the scientists added: "Estimates of the effectiveness of this system on R [transmission rate] are difficult to ascertain.

"The relatively low levels of engagement with the system (comparing ONS incidence estimates with NHS Test and Trace numbers) coupled with testing delays and likely poor rates of adherence with self-isolation suggests that this system is having a marginal impact on transmission at the

moment.

"Unless the system grows at the same rate as the epidemic, and support is given to people to enable them to adhere to self-isolation, it is likely the impact of test, trace and isolate will decline further in the future."