Encephalitis

Yesterday one of my work colleagues started acting strange. He'd been complaining about having a bad headache and feeling nauseous for a few days, but then when speaking to him he stopped making sense, forgetting other peoples names etc.

We took him to hospital and apparently he's been diagnosed with viral encephalitis. I've read a couple of websites and I'm scared for him as it looks as though there be may be some very long term problems in store for him down the line.

He's one of the nicest, funniest, sweetest guys you could meet and I'd hate to see him 'go'. Has anyone had any experience of this? I could do with some reassurance. I'm hoping it's not as black as I fear.