A Covid-19 study that's currently underway in the South Island is calling on the wider Southland community for help.
Southland District Health Board had the highest per capita infection rate at the peak of the covid outbreak.
Now scientists are trying to find out the extent of undiagnosed infection in the community through blood tests performed on contacts or close contacts of confirmed patients.
"The study is looking at antibodies to the covid infection to see if we can detect undetected or undiagnosed infections," said Dr Arlo Upton.
Dr Upton is a clinical microbiologist for Southern Community Laboratories (SCL) and leading the research study at the SCL facility at Otago Hospital.
"We are particularly interested in contact with confirmed cases in march and early April when we didn't have full testing capacity," Dr Upton said.
"Perhaps when there was a little bit of infection through the community being spread without us or public health being aware of it."
The teams hunt for signs of community spread has started by taking 800 samples but around 2000 are needed and time is running out.
Overseas research shows that even in confirmed covid cases, particularly where infection not very severe, antibody levels can drop off quite quickly - within just eight to 12 weeks - so the push is on to get tests done as soon as possible.
Dr Upton would like anyone who has been contact or close contact with any confirmed Covid-19 case to contact Southern Community Labs.
The team will arrange a blood test.