Historical cases reported in New Zealand, too
New Zealand has recorded six historical cases of COVID-19 in quarantine, in the week since Samoa officially reported that its two COVID-19 positive cases were in-fact historical and not infectious.
In daily press releases, the Ministry of Health reports its daily count of COVID-19 cases identified in quarantine through routine testing.
On Friday 29 November, Prime Minister, Tuilaepa Dr. Sailele Malielegaoi, revealed the Government suspected the two positive cases isolated in the national hospital were historical and not infectious.
This was finally confirmed with blood tests conducted in New Zealand which found evidence that the two men, a 23-year-old sailor and 70-year-old man, had been infected in May and August and posed no threat of infection in Samoa.
Since then, New Zealand’s routine quarantine tests have found 21 people with active cases COVID-19 and six which are historical.
One of those cases was identified on Saturday from the United States via Hong Kong. Their day 12 test (towards the end of their quarantine stay, following an earlier test on the third day of quarantine), showed they were positive and further investigations found the infection to be historical.
Five historical cases were identified on Thursday. Two were members of the Pakistan men’s cricket team, and will not be counted in New Zealand’s total cases because they were counted overseas.
One arrived in mid-November from Germany via Singapore, and two arrived mid-November from the Netherlands via Singapore. They tested positive on their day 12 tests and further investigation found them to be historical.
Last week, a Ministry of Health spokesperson explained the process New Zealand uses to determine if someone’s positive test result is evidence of a historical infection.
“A weak P.C.R. result can mean that either someone is at the beginning of an acute infection or are an historic case,” the spokesperson explained.
“In New Zealand our protocol is to repeat the P.C.R. test for anyone who has a weak positive P.C.R. test as soon as practicable.
“If the repeat P.C.R. result remains a weak positive or is negative then it suggests that the person is an historic case.”
Then it’s time to look at the case history of the person being tested. Have they been previously diagnosed with COVID-19? Or, did they have symptoms of the disease – fever, dry cough, tiredness, and more – and weren’t tested? Have they been to a country with many cases of the virus?
“If serology (blood) tests also show the presence of antibodies it can provide further confirmation that it is a historical infection,” the spokesperson said.