A recent returnee who returned a weak positive result for Covid-19 after completing their two-week isolation has been confirmed to be a historical case.
The Ministry of Health earlier today said the person's case was under investigation, but serology tests run today have shown the presence of antibodies that further confirm this is a historical infection.
A PCR test conducted today had also returned a negative result.
The person arrived from the US and went through 14 days in an Auckland managed isolation facility - where they returned two negative tests and were asymptomatic - before leaving on 21 September.
This week, the person sought medical care after feeling unwell and a subsquent test for Covid-19 returned a weak positive result.
An acute non-Covid-19 respiratory illness can sometimes create a situation where residual Covid-19 virus particles are detected when a sample is taken.
However, the ministry says there is no risk to the public and international research shows people with a historical Covid-19 infection are not infectious.
As a result, the ministry says no further management of close or casual contacts is required.