I've not heard that the canine influenza has made it overseas. They do have a pretty strong quarantine in place in the UK limiting the spread of disease into the dog population.
You can read about canine flu here
www.marvistavet.com/html/body_canine_influenza.html
Another possibility is fungal infection vs bacterial pneumonia. It might be an antibiotic resistant bacterial infection too.
A tracheal wash and a culture might give them a better feel for what is going on and what medication will work against the infection.
Nursing care and making sure the dog is eating and drinking may be significant in keep the dog going. Chicken soup (home made is best) can help keep a dog hydrated and is nutritious. A Nutrical type supplement probably exists in the UK though it may be under another name adn that sticky stuff can keep a non eating dog going for a good while.
The antiviral Tamiflu may help too if this is a viral disease.
www.marvistavet.com/html/body_oseltamivir.html
The lasix is a diuretic to make him lose fluids.
Hope this helps you!
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