▁ ▁See ▁also ▁Comm unes ▁of ▁the ▁May enne ▁department ▁ ▁References ▁ ▁IN SEE ▁commune ▁file ▁ ▁Saint g erm ain dan x ure <0x0A> </s> ▁The ▁discovery ▁of ▁disease - ca using ▁path og ens ▁is ▁an ▁important ▁activity ▁in ▁the ▁field ▁of ▁medical ▁science . ▁ ▁Many ▁vir uses , ▁b acter ia , ▁proto zo a , ▁fung i , ▁hel min thes ▁and ▁pr ions ▁are ▁identified ▁as ▁a ▁confirmed ▁or ▁potential ▁path ogen . ▁In ▁the ▁United ▁States , ▁a ▁Cent ers ▁for ▁D ise ase ▁Control ▁program , ▁begun ▁in ▁ 1 9 9 5 , ▁identified ▁over ▁a ▁hundred ▁patients ▁with ▁life - th re aten ing ▁ill ness es ▁that ▁were ▁considered ▁to ▁be ▁of ▁an ▁inf ect ious ▁cause , ▁but ▁that ▁could ▁not ▁be ▁linked ▁to ▁a ▁known ▁path ogen . ▁ ▁The ▁association ▁of ▁path og ens ▁with ▁disease ▁can ▁be ▁a ▁complex ▁and ▁controvers ial ▁process , ▁in ▁some ▁cases ▁requiring ▁dec ades ▁or ▁even ▁centuries ▁to ▁achieve . ▁ ▁Fact ors ▁imp air ing ▁identification ▁of ▁path og ens ▁Fact ors ▁which ▁have ▁been ▁identified ▁as ▁imp eding ▁the ▁identification ▁of ▁path og ens ▁include ▁the ▁following : ▁▁ 1 . ▁L ack ▁of ▁animal ▁models : ▁Ex perimental ▁in fection ▁in ▁animals ▁has ▁been ▁used ▁as ▁a ▁criter ion ▁to ▁demonstrate ▁a ▁disease - ca using ▁ability , ▁but ▁for ▁some ▁path og ens ▁( such ▁as ▁V ib rio ▁ch ol era e , ▁which ▁cause ▁disease