A method of treating a subject having a retroviral infection, by administering to the subject a therapeutically effective amount of a composition comprising a vector encoding a CRISPR-associated endonuclease and at least two guide RNAs, wherein the guide RNAs are complementary to two target sequences spanning from the 5′- to 3′-LTRs of the sequence in the retrovirus, and eradicating the retroviral infection. A method of immunizing a subject at risk of retroviral infection, by administering a prophylactically effective amount of a composition comprising a Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)-associated endonuclease, and two or more different guide RNAs (gRNAs), wherein each of the at least two gRNAs is complementary to a different target nucleic acid sequence in a long terminal repeat (LTR) of proviral DNA of a retrovirus to the subject, and preventing retroviral infection in the subject.
