The Holy Prophet SAW said: "No disease is contagious (in itself), taking ill omens is not permissible and there is no unluckiness in the owl and in the month of Safar." (Sahih Bukhari, Hadith No. 5380)
To believe that bad luck and misfortune descends in the month of Safar is superstitious. Muslims believe that everything comes from Allah, good and bad, and that He tests us in different ways. A test from Allah is not something evil, it is only good for the one being tested.