Taxi drivers have been left without "adequate protection and guidance" despite many working throughout the lockdown, industry leaders say.
Figures show the profession has one of the highest rates of Covid-19 deaths.
Drivers, taxi firms and industry bodies have said national safety guidance is urgently needed.
Government advice says drivers can refuse to take passengers who are not wearing face coverings.
Many companies now provide masks and hand sanitiser, but some drivers say they have to pay for their own protection at a time when they are struggling financially.
Some report being so "desperate" they have made DIY protective screens out of cling film.
Most taxi and private-hire drivers are male, and a high proportion are from black, Asian and ethnic minority (Bame) backgrounds - two of the groups at high risk from coronavirus.
Over the past three months, drivers say their main jobs have been transporting NHS staff, key workers, patients and the vulnerable.
'I thought I was going to die'
While most of us stayed at home, private hire driver Darren Hiles spent the start of lockdown working on Merseyside.
"I wasn't given a mask, but everything was a bit unknown at that time," he says. "Me being me, I thought I would be OK."
The 48-year-old was admitted to intensive care on 7 April, where he would spend the next six weeks, including four on a ventilator.
His partner Heidi Neilson was warned on several occasions that he could die.
"I couldn't believe what the virus had done to him," she says. "He looked like a corpse. I barely recognised him.
"Our kids wanted to see their dad and I had to wave them away because I didn't want them to see him like that."
Darren is now out of hospital but it may be a year before he can walk again. He is not sure if he will return to his job, but says his fellow drivers deserve better protection.
"I'm convinced I contracted coronavirus through my job. We were in lockdown when I was infected. The only interaction I had I was at home or at work."
Heidi agreed: "I work in a care home and we are given protective equipment. What makes me more deserving then a taxi driver who is also doing an important job?
"The supply should be there for any frontline worker. It's not just about the driver, it's about customer safety."
Why are taxi and private-hire drivers at higher risk?
Figures by the Office for National Statistics (ONS) show male taxi cab drivers and chauffeurs had higher rates of deaths involving coronavirus in England and Wales. Higher than doctors, nurses and care workers.
Scientists believe private-hire drivers are particularly at risk - and the longer the journey, the bigger the risk.
"Unlike black cabs, there is no physical barrier separating the driver and the passengers," says Dr Joe Grove, a virologist at University College London.
"People are close together and if the windows aren't open, the air can be quite stagnant.
"An infected passenger releases microscopic droplets containing the virus. Even after they've left the car, the virus will remain."
Sociologist Dr Mark Williams from Queen Mary University of London says taxi and private-hire drivers are among the worst hit because they face many risk factors.
"They can't do their job from home, and their job makes it hard to socially distance, but they're also self-employed so need to work."
While drivers can claim the government's self-employment income support scheme, worth 80% of their trading profits, Mr Williams says many are not eligible.
James Farrar, from the App Drivers and Couriers Union, said it was "unforgiveable" drivers had been working for the last three months without adequate protection and advice.
He added: "The government has given contradictory advice on masks and no regulatory guidance on plastic-screen partitions."
Currently, Scotland is the only part of the UK where it is mandatory for passengers to wear face coverings in taxis and private-hire cars.
In England, it is mandatory on public transport, and in Wales and Northern Ireland it is recommended.
A spokesperson for the Department for Transport in England said passengers needed to "think of the safety of drivers" and wear face coverings, even if they were not required to.
But Mr Farrar is concerned that the "burden of refusal" is on drivers who might face pressure to accept work from their firms.
Not all councils allow plastic partitions, and installing them is a cost many drivers say they cannot afford.
Matt Young, who co-owns Shrewsbury Taxis, said he had heard "horror stories" of drivers making screens out of "shower curtains and cling film".
He said screens should be properly fitted and meet official criteria.
He added: "We would recommend wearing a face mask. Sit as far away as you can from the driver with the windows open, use hand sanitiser and pay with your [bank or credit] card."