Secondary school and college staff in England will be tested weekly for Covid-19 from January, the government has announced. 

The Department for Education said that lateral flow tests would be deployed to all secondary schools and colleges to “help detect asymptomatic cases and break chains of transmission”. 

It is estimated by the government that one in three people who are infected with Covid-19 do not have symptoms. 

As part of the new testing programme, students who have been in close contact with someone who has tested positive for coronavirus will also be eligible for daily testing for seven days. 

Under current rules, everyone in a school bubble must self-isolate if someone within it tests positive for Covid-19. 

But from January, those who agree to daily tests will not have to self-isolate. School staff will also be eligible for daily testing if they have been identified as a close contact. 

Primary schools in England will be supported to roll out testing “as quickly as possible” over the spring term, the government said. 

Education secretary Gavin Williamson branded the news “a milestone moment in our work to keep schools and colleges open for all”.

“I know it has taken a phenomenal effort from everyone to ensure approximately 99% of schools have been open each week since the start of term,” he said. 

“Testing on this scale brings real benefits to education, it means more children, teachers and staff can stay in their classes in schools and colleges without the need to self-isolate.”

More than 600,000 pupils were off school at one point in November due to Covid outbreaks.

Test kits will begin arriving at secondary schools and colleges for the first phase of rollout to staff from the first week of January.

Dr Susan Hopkins, senior medical adviser to Public Health England and NHS Test and Trace said: “Lateral flow devices are a vital additional tool in helping us detect Covid-19 cases that we wouldn’t otherwise know about, meaning that we can break chains of transmission and save lives.

“In schools these tests can help make students and staff safer by helping us quickly identify many people who are unknowingly carrying high levels of the virus, preventing them from passing it on to others.”

The announcement comes after a row between the Department for Education and councils in London, which had advised schools to move classes online amid rising Covid-19 rates in the capital. 

Greenwich, Islington and Waltham Forest councils had all suggested that schools close their doors to all but vulnerable pupils and the children of key workers. 

However, in a statement on Monday night, Williamson said: “It is simply not in children’s best interests for schools in Greenwich, Islington or elsewhere to close their doors.”

He added: “I have always been clear that using legal powers is a last resort but continuity of education is a national priority. That’s why I won’t hesitate to do what is right for young people and have issued a direction to Greenwich Council setting out that they must withdraw the letter issued to headteachers on Sunday.”

On Tuesday morning Greenwich leader Danny Thorpe said he was left with “no choice” but to U-turn on his directive that schools should shut on Tuesday, after education secretary Gavin Williamson said the government would sue.