You are already being too paranoid for right now . Though this may change if Wuhan Corona virus becomes far more widespread.
Apart from the very small probability of coming into contact with a Wuhan Coronavirus carrier unless you are in/around Wuhan as mentioned in another answer you need to consider the following:
300,000 to 650,000 people die from Flu each year. Would you be at all considering raising the alarm to cabin crew if you suspected the person next to you had flu? All you would be doing is creating hysteria in possibly the worst place for it to happen - an aircraft cabin.
Right now (end Jan 2020) Wuhan CoronaVirus is much less deadly than SARS and MERS were and is far less likely to kill you personally in Munich or London than Flu would*.
- Assumming you are a fit adult of young to middle age - its also vanishingly unlikely that you will be killed by Flu.
Instead of speculating around unlikely (at this point in time) scenarios start educating yourselves and others about what the actual risks are.
So based on this site
Wuhan Coronavirus may spread more easily than flu (exactly how much is still uncertain), will kill more easily than flu, but not SARS or MERS.
Right now there are are 2 major worries about CoronaVirus - the fact that it may be contagious whilst the patient shows no symptoms, and that it seems to spread relatively easily for a droplet-borne virus - BUT at time of writing - neither of these things have been confirmed with statistical rigour.
In short - if you are flying you way more have more chance of sitting next to someone with flu than sitting next to someone suffering from Wuhan Coronavirus. This last statement is a WAG and lacks statistical rigour - but hopefully it makes the point.
Bookmark the site above and then start worrying if the number of cases reaches the 100,000 mark.
Bear in mind the media exists (in part) to sell advertising via manipulation of your emotions - particularly fear.
Right now there is nothing to suggest that WCV is going to be much much worse than SARS or MERS were. Not to trivialise those deaths but to put into context their minimal global impact to the average human.
One tip I use - change the headline to something more prosaic - at time of writing WuhanCorona Virus has killed 132 people since December 2019. In 2018 an average of 3056 people died in car crashes in the US. Source
Would you be worrying as much if you saw the headline 132 die from Virus, vs 132 die from Driving?
One last thought : The human brain is appalling at judging relative risk - always bear this in mind.