https://www.theguardian.com/politics/2020/apr/02/no-10-seeks-to-end-covid-19-lockdown-with-immunity-passports
I understand the importance of testing healthcare staff and other essential workers to see if they have #Covid19 now and possibly for antibodies to see if they've gained some immunity through a previous infection. But 'immunity passports' for us all? 1/11

2/11 This is a policy that creates a potential dystopia. Antibody+ people, who are seen as unlikely to infect anyone or to be reinfected themselves, are allowed to go back to work. But those who appear *not* to have had coronavirus are left under some kind of house arrest.

3/11 We don't need a PhD in Behavioural Science or Psychology to realise that some people would be *looking* to get infected or to fake results. Not because they were devious and immoral, but because they were desperate for work or to see loved ones.

4/11 You're a self-employed tradesman who competes with others for work on local building sites. But your test comes back negative for antibodies. The job on that newly re-opened building site is going to go to someone else. If only *you'd* had Covid-19 too!

5/11 People from your university are going back to classes, but you're not. They were 'lucky' enough to have contracted coronavirus early in the epidemic and have the antibody test to prove it. You don't and are stuck back at home with your parents.

6/11 Home testing is the only convenient way of getting a large-scale passport scheme up and running - particularly in an environment where we're all social distancing - but what's the point of getting a result unless it is validated?

7/11 I need to go back to work, so I ask a friend who had that persistent cough a few weeks ago to lend me a few drops of blood.

8/11 It's nice weather in the summer and all the antibody+ people are out in the park. If I join them, what are the chances of the Covid police picking me out from the crowd and asking to see my passport? Maybe I'll take the risk. Who'll know?

9/11 To police this scheme, you would need intense and large-scale surveillance on an unprecedented scale. Passports would have to be checked left, right and centre. The alternative is complete chaos. Buses full of positives and false positives and negatives faking positive.

10/11 I've tested negative. But I really want to be positive. So when do I get my *next* test? I might have caught it in the meantime. I don't have any symptoms? But I've been told I can catch it asymptomatically. So please test me again. And again. And again.

11/11 At best, I foresee a comical fiasco. At worst, I envisage social division, resentment and many unintended consequences.