The number of people who contracted coronavirus linked to a wedding on the New South Wales South Coast earlier this month has risen to 35.

Key points: The number of cases linked to the gathering at Stanwell Tops has risen since six were confirmed earlier this week

The number of cases linked to the gathering at Stanwell Tops has risen since six were confirmed earlier this week NSW Health says it is working with other states and territories to notify attendees

NSW Health says it is working with other states and territories to notify attendees The retreat says all staff who worked at the function are in good health and so are their families

Six confirmed cases emerged earlier this week from the gathering at Tumbling Waters Retreat, Stanwell Tops, on March 6.

It is understood the cases may have been connected to travel from the United States.

Cases spread interstate

In a statement, NSW Health said it was also working with other states and territories to notify attendees.

"To midday on March 19, there have been 26 NSW residents who attended the wedding who have been diagnosed with COVID-19," it said.

"There are another four people, NSW residents with COVID-19 who are close contacts of wedding attendees with COVID-19.

"NSW Health is aware of another five people with COVID-19 who attended the wedding but live interstate."

Sally Hawach, the daughter of advertising mogul John Singleton, said she and her husband, Pierre, tested positive for coronavirus after attending the wedding.

Ms Hawach, who is pregnant, said it was almost seven days before she was tested and was worried she had infected others.

"During that week I didn't feel sick, but I probably had it and could have spread it.

"I had to go through and call everyone; luckily there wasn't too many people, but it's an awful thing to have to say to people, 'Oh, you may have been in contact with it', to think that they may have passed it on to somebody elderly or sick."

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Venue says all staff tested negative

In a statement posted on Instagram on Friday, the luxury retreat said all staff who worked at the function were in good health and so were their families.

"They are due to come out of self-isolation today as recommended by NSW Health," it said.

"The staff that were eligible for testing for the COVID-19 virus, all tests returned negative. Not positive. Not contagious."

The statement went on to say it was working closely with NSW Health and following its guidelines.

It said the source of the contagion was still unclear, hence the reason why the business was not contacted in the initial stages of the outbreak, adding that the situation only came to its attention 10 days after the event via the media.

The retreat said its accommodation business was open and would do its best to continue to pay staff.

"I feel that when this nightmare is over, our team will be busier than ever. We all just need to not panic, keep rational and weather the story."

NSW Health has confirmed none of the seven COVID-19 cases in the Illawarra and Shoalhaven are connected to the wedding.