Earlier this morning, the vaccinators and I had our second dose of the Pfizer vaccine. A moment of comfort to know that 2 weeks from now we will have an extra layer of protection from severe illness or death, should WE come into contact with the COVID-19 virus.
Over the weekend, New Zealand reported that there have been 67 historical cases among 510 cases screened at the New Zealand border this year, since 1 January 2021.
One of those cases was also detected on our shores at the end of last week. This person is a Cook Islander who works overseas and returned here on holiday. While in New Zealand quarantine, the person tested positive for COVID-19 on Day 0 and was moved to an isolation facility. The New Zealand authorities determined that the person who was asymptomatic and based on the laboratory findings (serology) of the coronavirus is an historic case. That is, he contracted the viral infection but due to his strong immune system or low infectivity of the virus, he just had mild infection, recovered and is now no longer infectious. At the end of his isolation period in New Zealand he was discharged and allowed to move freely as he wished.
He came to the Cook Islands and joined his family. Because the overseas country where he works requires people to have a COVID test before entering their country, he requested a test from Te Marae Ora. Our alarm bells started ringing when the test came back positive. He was tested again together with his family and several close associates who all tested negative.
Only then did it come to light that he had tested positive in New Zealand, and that this is an historic case. The negative test results of his family and the close contacts reinforce the fact his is an historic case.
So, what does being asymptomatic mean and what is an historic case?
Asymptomatic means that although a person may have been infected and tested positive for the virus, they are not displaying or suffering from any of the symptoms normally associated with COVID -19 infection and many thousands of cases like that have been reported all over the world.
Historic case means a person had contracted the virus and had recovered and is no longer infectious.
Both New Zealand Ministry of Health and Te Marae Ora Cook Islands Ministry of Health use a test called RT- PCR; it is the gold standard to test COVID 19 virus infection. In the test we look for the positive and negative results as well as for the cycle threshold or CT value. If the value is high (> 30-35) with a positive result, it can be a false positive result, indicating that the person has contracted the virus, and the person’s immune system has attacked and defeated the virus leaving only non-infectious virus debris in their system.
This can be confirmed by using another molecular test, GeneXpert and the serology.
That is why after a first positive test, health authorities wait a few days before taking another sample to see if the CT value changes, if it continues to be high it is an indication that the positive test is a false positive, and the virus is likely to be non-infectious. The immune status of such persons can also be confirmed by a blood test (serology) and if it shows only antibodies, it is an indication that the person was exposed to the virus and the body immune system has defeated the virus and it is an historic case.
There is evidence from other countries that the RT- PCR tests can continue to be positive for a few weeks or months due to the presence of non-infectious viral debris.
However, this case is a wake-up call, and we need to learn from it.
We need to continue to be on our guard. People need to truthfully answer the health questionnaire taken before each flight. We have endured the economic pain of lockdown and the closing of our borders and are only now taking baby steps back to recovery.
Most of us have had our first COVID-19 vaccine jab and the second will be due soon. Finish the course. Your health and safety and that of your family and friends, and our country as a whole, depends on it.
Secretary of Health