Cudurkan waxaa keena nooc ka mid fayraska oo loo yaqaan HIV (Human Immunodifeciency
Virus), feyraska noocani waxa uu toos u weeraraa unugyada difaaca jirka Aadamiga,
weerarkaas kadib hidda-sidaha Feyraska HIV-ga (DNA) waxa uu toos ula midoobaa hidda-sidaha
qofka bukaanka (DNA of the host), waxaana dhacda in ay mideysnaadaan muddo aan yareyn
inta badana lagu qiyaaso 5-10 sanadood, xilligaas oo qofka bukaanka ahi uusan muujin
wax calaamado cudur ah (Assymptomatic period).