Humidity causing keyboard damage?

[Zoefulton]

I'm from the states and came on vacation to Malta it is very very humid here so much my hands and feet are constantly swollen. Now I am not sure if I have a hardware problem or a software problem. The first few days I was here my laptop functioned normally but it wasn't that humid. The last two days have been very humid and it seems my keyboard and trackpad have suffered some water damage I'd use it fine for 15 minutes then the keyboard would right click and keys would put out the wrong letter and such. I have a late 2009 MacBook that has suffered liquid damage in the past but was cleaned out and returned to functioning normally about a year and a half ago. So last night if use it for 20 minutes ish and it'd act up then I'd set it down for an hour and it'd return to normal functioning for another 20 minutes I've tried updating which went along normally and today I think it's just the keyboard I plugged in a USB mouse I brought along and it still right clicked so I think the shift button is stuck thinking its down. It's essential I use my computer here. What can be done? I've tried using it with a fan pointed at it but still happens. Could it also be a software issue? And today it doesn't even work for those 20 minutes. I tried disk and permissions repair and resetting the pram but I can't because the option button isn't functioning and hasn't been for some time. (Both of them) and I haven't brought my USB keyboard along. Any ideas? If it is a software issue how would I go about fixing it?