1, the presence of HPV subclinical infection and latent infection. 2, Incomplete treatment of warts. 3, incomplete treatment of sexual partners. 4, poor autoimmunity, such as combined with HIV infection. 5, the local environment is humid, such as male circumcision or circumcision, female leukorrhea or vulva humid. 6.Pregnancy. 7.Self-inoculation transmission. 8, contact with objects contaminated by HPV. 9, excessive psychological and mental stress, long-term depression and tension. 10.Follow up regularly according to medical advice. 11, excessive smoking and alcohol consumption.