Is there any effective device we can use?
I have OFF but they are not intended for indoor use. And they are not that effective in my experience.
On Amazon, there is Thermacell which uses chemical. I'm not against chemical but it uses Butane cans. For a long trips, I'd have to take a lot of cans.
The other type is the electric zapper. One popular one is Gloue. They are small and the reviews are very good. But I'm not sure if they are effective in the swamp.