The government is facing fury from workers and unions after leaked emails revealed that firms could temporary furlough workers needing to self-isolate – but that this clause was omitted from official guidance about the Coronavirus Jobs Retention Scheme.

Political website Politico.eu claims the UK Treasury instructed government officials to conceal a little-known provision that granted sick pay to people isolating due to coronavirus at the height of the pandemic.

Emails between senior civil servants, seen by the news website, show that ministers refused to publicise this option in official guidance in case it led to workers being furloughed “who did not need to be”.

Since the pandemic began the low levels of statutory sick pay at just £96.35 a week has been a major factor in workers with symptoms of Covid-19 feeling unable to self-isolate. In contrast, if a worker is furloughed they receive 80% of their pay.

Concerns about the lack of financial support while self-isolating was particularly prevalent in the food industry, especially meat processing where social distancing is often limited and there have been a large number of Covid-19 outbreaks.

Joe Clarke, Unite union national officer, said: “This revelation is absolutely disgusting and demonstrates that the government acted recklessly with the safety of workers. The government cynically suppressed this information from businesses at a time when over a 1,000 people a day were dying from Covid.

“Since the beginning of the pandemic Unite has consistently called for an increase in sick pay as workers cannot afford to self-isolate on less than £100 a week. It is simply astonishing that the government had in place measures to tackle the problem of poverty while self-isolating but cynically decided not to tell anyone about it.

“This decision will have cost lives, led to increased infections and meant that successive lockdowns have lasted longer than necessary, further damaging the economy. This is a government that has been shown to have repeatedly given huge contracts to their friends. But when it comes to the workers who have kept the economy going through the pandemic, they suppressed the information needed to keep them safe and financially secure.”

GMB union described the reports as ‘scandalous and incompetent’.

Rachel Harrison, GMB national officer, said: “Poverty sick pay rates are causing higher infection rates in care homes and other workplaces. We have one of the lowest statutory sick pay rates in Europe and reform is long overdue.

“Suppressing advice on furlough eligibility during self-isolation is scandalous and incompetent. Lives will likely have been lost and higher infection rates will cost the NHS and employers far more in the long run.”