Give it a try, it may work.
I know it works when the tea is lookwarm and also, inexistent (the first night I just left the empty mug with a used bag in my nigthstand. I could hear one of the last mosquitoes buzzing close to the ceiling, coming and going (I even heard an annoyed buzzing, like: food, food, food... oh, fuck, that smell, no!), when at that point they would have already tried to bite me a dozen times. They didn't reach me until morning, when the mug and bag had already dried out.
It even works with a bottle that closes in a vacuum, seems like I only need to open it and take a sip.
As of now, there's no sign of them.