I know we read stories like this one every day from country x, y or z but this seems to have some credibility. Key takeouts:
1) Blood based (rather than saliva) antibody testing has started locally in Italy
2) Immunity is thought to last months rather than years
Italy puts faith in coronavirus antibody test to get country back to work
Two Italian regions are testing doctors and nurses for coronavirus antibodies in an effort to build up an army of medical staff with immunity to work in the most infected isolation wards.
The plan for “immunity licences” in the regions of Veneto and Emilia-Romagna in the north was announced as the government plans a national roll-out of antibody testing to get people back to work.
“We got up the courage to go first because this is so important,” said Mario Plebani, of the University of Padua, who is managing testing in Veneto
While saliva can be tested to see if a subject has the virus, blood testing can discover if someone has had it and has developed antibodies to stop it returning. Rome sees immunity testing as key to getting workers back to essential industries, possibly on Tuesday.
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Rather than using portable kits that are said to lack accuracy, Veneto is taking blood samples to a laboratory for testing. “We are still experimenting,” he said. “Since we know that many doctors have been infected, if this test shows they have no antibodies we will know it’s not accurate.”
The blood test identifies two types of antibody, one which reveals contact with the virus and a second showing if the body has built a defence against it. “Our tests show the second appears 12 days after the first symptoms and remains strong for 35 days. After that we don’t know,” Professor Plebani said.
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In Emilia-Romagna, the authorities started testing doctors and nurses and care home staff for antibodies on Monday and plan to check up to 100,000 in 15 days. “We tested it in one town and it works,” a spokesman said.
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The government is “within hours” of selecting the kit it wants to use for nationwide testing, but is being more “prudent” than the regional governors who have jumped first, said Walter Ricciardi, a member of the World Health Organisation’s executive board who is advising Italy. “We are studying this carefully so we don’t pick a set-up which gives false results,” he said. “We now think one does acquire immunity after getting the virus, but not permanently. We are probably talking about months rather than years.”
https://www.thetimes.co.uk/article/italy-puts-faith-in-coronavirus-antibody-test-to-get-country-back-to-work-q9qhvbmw0