Up to seven home support workers may have been exposed to Covid-19.
The two groups are now in self-isolation as they wait for the results of a family member of a client to get their results back.
There were 76 new cases of Covid-19 in New Zealand announced yesterday, taking the total to 589.
Twelve people are in hospital, three are expected to be discharged soon.
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Greymouth woman Anne Guenole, 73, is the country's first fatality from Covid-19. She had been admitted to Grey Base Hospital in Greymouth on Wednesday with suspected influenza before dying on Monday.
E tū union understands up to seven workers could have been infected and are now anxiously awaiting results.
"I've been into the client's home several times during the global pandemic," the person said. "The job requires two support workers because we have to lift the client, so there are a few of us who might be affected," they say.
"One support worker has also started a job at a local rest home recently, on top of her home support work, so we're really worried about those residents as well."
Test results are expected tomorrow.
E tū director Kirsty McCully said this demonstrated the "massive need for proper PPE in home support".
"It's just ridiculous that so many frontline health workers that care for vulnerable, elderly people, are not being given the right equipment," McCully said.
"All it takes is for one person to get Covid-19 and spread it to other clients, or even around a rest home, for the virus to spin out of control.
"Home support workers have a simple message – get us PPE and manage the risks properly to minimise the spread of Covid-19."