occupier [occupiers](one who occupies) noun [UK: ˈɒ.kjʊ.paɪə(r)] [US: ˈɑː.kjə.ˌpaɪər]
preoccupanteadjective
anxious(accompanied with anxiety; worrying) adjective [UK: ˈæŋk.ʃəs] [US: ˈæŋk.ʃəs]
worrisome(causing worry; perturbing or vexing) adjective [UK: ˈwʌ.rɪ.səm] [US: ˈwɜː.ri.səm]
worrying(inducing worry) adjective [UK: ˈwʌ.rɪ.ɪŋ] [US: ˈwɜː.ri.ɪŋ]Ebola seems to be spreading at an exponential rate, which is very worrying to say the least. = L'ebola sembra diffondersi a un ritmo esponenziale, che è molto preoccupante per non dire altro.