Schools in England are expected to be told to overhaul the curriculum, stagger break times and group children into “bubbles” when they return to the classroom in September, according to guidelines to be published by the Government.

Education Secretary Gavin Williamson is due to announce the plans for getting all pupils back after the summer following up to six months at home – on the same day schools in Leicester close again as part of the city’s lockdown extension.

The Daily Telegraph reported that a draft of the official guidance also bans the mixing of year groups – such as in assemblies – as well as school choirs, and suggests teachers also stagger the start and end of the day.

Contingency plans must also be in place in case of a local lockdown, the paper said, and schools will be required to liaise with their local health protection team if there are two or more confirmed coronavirus cases within a fortnight.

A general rise in sickness or absence where Covid-19 is a suspected cause could lead to a year group or the whole school being told to stay at home and self-isolate as a precaution.

Details are expected to be set out at a Downing Street press conference on Thursday – the first time one has been held since daily briefings were scrapped last week.

Meanwhile, schools in Leicester will be closed on Thursday and will not reopen until after the summer break.

Figures released in Public Health England’s preliminary investigation into the Leicester outbreak – released on Wednesday evening – suggested a slight drop in the infection rate in the city from the week to June 20 to the seven days prior to June 27 – down from 140.2 to 135.7 per 100,000 people.

The data also suggests the overall infection rate in England fell over the same period from 10.7 to 6.7 per 100,000 – despite the easing of some lockdown restrictions.

Rates in Bradford, Barnsley and Rochdale declined more sharply over the same period. Officials in regions with high infection rates have said they are working hard not to follow Leicester into lockdown.

The report also suggested the majority of recently confirmed cases are in people aged 18 to 65 years – with the median age of those infected standing at 39 years. And 50.9% of the cases reported in June in the city were in women.

The wards of North Evington, Belgrave and Stoneygate had the highest number of cases reported between June 11 and 25.

But the report concluded evidence for the scale of the outbreak was limited and an increase in reported cases could be partly due to a rise in the availability of testing.

The Office for National Statistics will on Thursday provide new figures from the coronavirus infection survey for England, and the latest data on the NHS Test and Trace programme will also be published.

It comes as the economic challenges of the pandemic were laid bare by a continuing jobs bloodbath.

The John Lewis Partnership warned over store closures and job cuts and Sir Philip Green’s Topshop empire revealed redundancy plans on Wednesday.

Upper Crust owner SSP announced up to 5,000 roles could go following plunging passengers numbers at railway stations and airports.

And Unite the union said its research revealed that almost 12,000 aerospace job losses have been announced in recent months at some of the UK’s biggest companies, including 1,700 by Airbus earlier this week.