The UK’s coronavirus test-and-trace system will not function unless ministers boost statutory sick pay (SSP) to ensure that workers can afford to stay at home, the head of the TUC has said. Speaking shortly before the union movement’s first virtual annual congress, Frances O’Grady said that 4 in 10 workers would be plunged into financial hardship if forced to self-isolate for two weeks, according to a survey. Millions of low-paid workers either do not qualify for the statutory sick pay of £95.85 a week or cannot afford to live on the allowance, leaving them unable to pay bills if they have to quarantine due to coronavirus. Boris Johnson was accused of incompetence by Keir Starmer at prime minister’s questions on Wednesday after hundreds of Britons reported that they could not access tests for the virus. The survey – carried out for the TUC by BritainThinks – shows that two-fifths (43%) of workers would be unable to pay their bills if they have to survive on the statutory minimum SSP. O’Grady said: “Asking workers to self-isolate on £96 a week is not viable – especially when many don’t have savings to fall back on. “We can’t have a situation where people are forced to choose between their health and paying their bills. “Unless ministers fix this gaping hole in our safety net Britain will be ill-prepared for a second wave of infections or more local lockdowns.” O’Grady spoke to the Guardian as TUC officials prepared for an online annual Congress for the UK’s unions, which will take place on 14 and 15 September, broadcast from the TUC’s central London headquarters. It will take place with a backdrop of mounting job losses following the coronavirus outbreak, a possible further downturn if there is a no-deal Brexit and with some of the bigger unions facing internal issues including divisive elections. O’Grady said she was “sad and angry” about the institutional sexism and sexual harassment uncovered by an independent report into GMB after the general secretary, Tim Roache, stood down this year following anonymous allegations of misconduct. The inquiry by Karon Monaghan QC concluded that “bullying, misogyny, cronyism and sexual harassment are endemic within the GMB”. O’Grady said: “When I was in my 20s this was a battle as an activist I was involved in, was a campaign against sexual harassment. And we were always fighting on two fronts, in the workplace, and in our own movement. “The idea that we’re still fighting that same battle makes me sad and angry. I draw some heart from the fact that it was the GMB that commissioned this independent report and took the decision to publish it.”. O’Grady criticised the government’s threats to break the law over the agreement, saying that Boris Johnson is playing a game with the livelihoods of millions of people. She said Johnson should follow the example of union negotiators who know that they have to keep their word or discover that others will lose all trust. “Stop posturing and do what the government promised it would do, which was get us an oven ready deal that was good for the working people in Britain too. Get on with it. And deliver a deal, because the prospect of further unemployment when we’re already struggling through a pandemic is frankly unconscionable,” she said.