I think that every time we experience something new we feel like novices!
Lungworm treated like any other worm - so a worming drench. We used ablex (on advice of vet).
The test is a FEC, but as said requires a bit more than most vets can do on site.... so we collected a sample from about ten of our flock, it was sent away and results in 2-3 days showed lungworm larvae.... Have drenched the whole flock (first time that's been necessary in four years), and now all look fab and no coughing!
In fairness, vet was surprised, and only tested for that at our request....
As ever, it may something or nothing.... ho hum!