i would say it's a fairly isolated incident. We cannot pass along many bacteria and viruses to our birds simply because what thrives in our bodies, will not thrive in theirs.
We have a body temp of approx 37degrees c (it's 37.6 or something) whereas birds have a body temp of between 40-43 c. So basically, the virsus and bacteria that attack our bodies cannot handle the temperatures in a birds, they cannot spread and multiply, etc. So they'll die off. There are so many other factors, but internal temperature is definitely one of the biggest ones.
We recently spoke to our vet about mites, about potentially our bunnies passing them to our birds if there was a mite problem. We were reassured, again for temperature reasons, that the mites on our buns would dislike our birds overall bodies, for temp etc, and so wouldn't go for our birds. Same applies for bacteria and viruses.
So although there are some zoonotic illnesses that we can pass between birds and humans (avian flu, obviously being the most well known) there are actually not that many and so there's no need to go into panic mode. If you know you have a zoonotic illness (and some that are 'zoonotic' can only be passed between say, human and pig, not bird, so you'd have to check specifics) then obviously, stay well away from your bird, potentially ask for someone else to care for them, or ensure that a vet is somewhat on standby knowing what you have and what would be needed to treat.
If you get sick, i'd just say limit your contact with you bird/bird area, if you have a partner who isn't sick, ask him/her to take over until you're better, but most importantly practice good hygiene.
I could maybe (with some others help) conduct a list of which illnesses to look out for?
Strep itself is not usually a zoonotic illness, but there are different strains and types if strep that are. So although wharfrat probably knew he had strep, he probably didn't realise that he might possibly have the strain that could infect his birdies - as most people wouldn't. Who get's themselves tested to know the extract strain you have? So it's important to just be vigilant, but if you've just got the sniffles, don't panic too much, just be aware.