Sorry. Taking a train and boat to Sweden is not going to cut it.
We are aware of the risks, and we do everything to mitigate it--which includes pre-boarding due to medical needs. We wipe down all hard surfaces in our row, plus search under the seats (and cushions) and in the seat pockets for anything unpleasant.
Miss Swede has done 12 TATLs and numerous domestic segments. Only once have we had to use an Epi-Pen in-flight, and that was very precautionary--to this day we're not sure if it was actually an anaphylatic reaction. Fortunately, that was on approach to DEN, so we landed quickly and were met by paramedics on the jet bridge.