Not a math related post, just common sense this time. (It is inspired by WHO (which has great scientists if lousy leaders no matter what our both scientifically illiterate and innumerate president says), pointing out there is no evidence yet that having the virus means you would have enough antibodies to prevent another infection. Sure, you may have a milder case but they can’t confirm that you can’t become an asymptomatic carrier if you get infected again. That means the whole notion of an “immunity certificate” is not going to happen anytime soon.
So what does this mean for travel for me (and I think many other people in “high risk” groups). Since there won’t be an immunity certificate, I won’t travel on public transportation unless everybody I’m going to encounter is certified virus free. We need to institute a system of travel where not only are masks required for everybody, social distancing maintained, you also need a special travel document that certifies you are virus free.
My first question is how long will a certificate be good for? The problem is the time between when you test negative and when you get to the airport!
Suppose someone tests negative for the virus. For how long are they safe? After all, they could get infected after their negative test but before they get to the airport. So we need to know how long could it take if you get infected before you start shedding virus. Is it 12 hours, 24 hours, 48 hours? Haven’t seen this answered anywhere, we need to know the answer to this! Anyway, once we know a person’s “safe interval”, we would know how long a certificate is good for and so how long before your flight you will have to line up to be tested.
This will no doubt add a couple of hours to the time needed to travel and remember you will probably need a new certificate for the flight back. How can the need for a certificate coming and going not make air and other forms of travel far less pleasant – perhaps to the point where, if you can afford to do so, you would drive more, take a train or bus never and so only get on a plane for special occasions. Airlines (and train and bus – where travel certificates are also going to be necessary) companies aren’t going to get better anytime soon. This certificate requirement is probably hopeless for public transportation, so looks like I’m only using my car for the foreseeable future. And, of course prices will have to go up because fewer people will want to deal with certificates. And, so as usual, poorer people are so screwed.