Coronavirus: Which countries have tried circuit-breaker lockdowns and have they worked?

Sir Keir Starmer has called for a two- to three-week national lockdown, accusing the prime minister of "no longer following the scientific advice".

The Labour leader's intervention came after it emerged Boris Johnson dismissed a recommendation for the measure from government scientists three weeks ago.

Here’s a look at how other countries have attempted a so-called "circuit-breaker" in their fight against Covid-19.

The city-state first reported cases of coronavirus in January but local transmission was largely kept under control until March when the government urged Singaporeans living overseas to return home.

Prime Minister Lee Hsien Loong announced the circuit-breaker in early April, forcing non-essential workplaces to close, schools to move to home-learning and businesses selling food were only able to offer take-away services.

The circuit-breaker was due to last for a month, with Mr Lee saying: "We have decided that instead of tightening incrementally over the next few weeks, we should make a decisive move now to pre-empt escalating infections".

Cases in the country continued to rise, peaking at 1,426 new cases on 20 April, and the circuit-breaker was extended until 1 June.

After it was lifted, the prime minister said the measures would not stop the outbreak in the country.

Mr Lee said: "As we ease up, I expect the number of cases to rise somewhat, as has happened in other countries. So we are moving cautiously.

"We want to avoid the numbers shooting up again, and having to impose a second circuit breaker. We will step-up testing and contact tracing significantly. Then we can catch new cases early, isolate them and their contacts, and stamp out clusters before they grow."

Many of the cases post circuit-breaker have been found among migrant workers living in dormitories, with a spike in cases in August. The government said there were no new locally acquired cases on Tuesday.

The period of the circuit-breaker coincided with a 13.2 per cent contraction of GDP on a year-on-year basis, with the Ministry of Trade and Industry adding: "The fall in GDP was due to the Circuit Breaker (CB) measures implemented from 7 April to 1 June 2020 to slow the spread of Covid-19 in Singapore, as well as weak external demand amidst a global economic downturn caused by the Covid-19 pandemic."

Israel is expected to emerge from a national lockdown this week after attempting a traffic light-style system — similar to England's tiers plan — where areas with high infection rates faced the harshest measures.

The country, which had one of the highest infection rates per capita, introduced the measures over the High Holidays of Rosh Hashanah or a three-week period.

Starting on 13 September, people could not travel further than 500 metres from their home unless for essential activities, there were closures of non-essential stores, hotels and restaurants and a limit of 10 on gatherings.

More severe measures came in just over a week later, including the forced closure of synagogues except for during Yom Kippur. The measures were expected to be lifted on 10 October, but were extended for another week.

In a statement on Sunday, Prime Minister Benjamin Netanyahu said: "I know that the lockdown is very difficult for all of us but I am certain that most of the public understands today that the decision I led regarding the lockdown was necessary.

"It saved us from a geometric increase in morbidity, mortality and severe cases and it is still too early to get ahead of ourselves.

"There are preliminary signs of success. However, we need another few days to evaluate this. The exit will also be gradual, responsible and cautious."

Infection rates in Israel increased during the lockdown according to Johns Hopkins University figures – from 4,764 new cases on 14 September to more than 11,000 on 23 September. The most recent figures show 3,538 new cases for 12 October.

Prime Minister Jacinda Ardern put the country into Covid-19 Alert Level 4 — or a national lockdown — at midnight on 26 March. An emergency alert was sent to New Zealanders saying "where you stay tonight is where you must stay from now on" and "you must only be in physical contact with those you are living with".

The measures saw non-essential services, such as bars and restaurants, closed, while supermarkets were allowed to remain open.

The Alert Level 4 ended on 27 April, a week longer than expected.

Ms Ardern said: "We considered that the longer we are in lockdown, the less likely it is we will need to go back. We also considered moving alert levels on 23 April, which is in just 48 hours' time.

"The sacrifice made to date has been huge, and cabinet wanted to make sure we lock in our gains, and give ourselves some additional certainty."

On 18 April, New Zealand recorded 13 new cases but did not have another day in double digits until 12 August.

PA