Andrew ‘Twiggy’ Forrest’s daughter says vulnerable workers exposed to COVID-19 have been 'let down' by business and governments

Modern slavery watchdog Walk Free Foundation is urging businesses and governments to help reduce COVID-19 risks for vulnerable workers, citing a massive outbreak among migrants crammed into dormitories in Singapore under extended lockdown measures.

After months of controlling the spread, cases in the city-state have surged by the thousands, with the vast majority of second-wave infections linked to the dorms.

The construction workers, largely from Bangladesh and India, are confined to their crowded rooms until May 4, and have reported insufficient cleaning services and no personal protective equipment, despite government assurances they would be able to socially isolate.

They were also excluded from a government program to distribute masks to households, the Perth-based foundation says in its special Protecting People in a Pandemic report released today.

"People are being let down," co-founder Grace Forrest, the daughter of mining billionaire Andrew Forrest, told AAP.

"If we leave these populations behind, it is absolutely morally wrong ... and it also creates incredible vulnerability to the entire population."

The workers had also complained of inadequate food and Ms Forrest said she had heard the words "mass starvation" every day in relation to migrant workers, many of whom were trapped in countries they had moved to or been trafficked to, with their passports confiscated by their employers.

The reports lists ways companies can try to ease the impact of the crisis on workers, with measures including paying suppliers up front or shortening payment terms.

Many companies weren't absorbing the economic hit of lost business caused by COVID-19 and were instead making their low-paid workers suffer, she said, singling out British fashion retailer Primark.

"How ridiculous ... it's completely unfair."

She said some of the other offending industries included fishing and agriculture.

The expression "we're all in this together" had been used widely in discussing the pandemic, but it appeared to apply only to those who could afford to socially isolate or work from home, she said.

The foundation's advice for governments includes ensuring undocumented migrant workers have access to virus testing and health care.