Acetic acid can make the HPV infected area tissue turn white, using this property can detect HPV infection especially subclinical infection, is a simple applicable and more accurate method. 1, acetic acid white test operation method: with a cotton swab dipped in 3% to 5% of glacial acetic acid, applied to the suspected damaged skin and its surrounding, generally after a few minutes can be observed in the local warts or skin tissue whitening. The fastest results can be observed about 1 minute after the application of the drug. However, in the vulva or perineum of women, it sometimes takes 3 to 5 minutes before it is easily observable. When examining men, especially the penis and scrotum, you can cover them with 3％ to 5％ of acetic acid-soaked gauze for 2 to 3 minutes and then look at the vulvar skin with a magnifying glass to find hidden areas of acetic acid whitening. The perianal area may take longer to turn white due to thicker skin stratum corneum. 2, white acetate test principle: the white acetate test can make the inconspicuous subclinical manifestations become visible to the naked eye, its principle of action is still unclear. One view is that the whitening is the result of protein coagulation, and that this protein reflects the abnormal cells and cellular excesses characteristic of HPV-infected epithelium. Another view assumes that the keratin of HPV-infected epithelium is different from that of normal uninfected epithelium, and that only the former can be whitened by acetic acid. 3. Presentation of the white acetate test: Following the use of acetic acid, colposcopy of subclinical HPV infection of the cervix is characterized by shiny, snow-white lesions with irregular jagged, angular or feathery margins. Diffuse, satellite-like lesions are seen beyond the migratory zone, along with capillary images, usually consisting of vessels of the same diameter in a loose, disorganized arrangement often resembling a sieve on a horizontal surface, and dilated capillary collaterals may also extend vertically to the surface, spreading throughout the lesion with the same canal diameter. If the vascular image is not obvious enough due to the constriction of small blood vessels caused by acetic acid, a green filter can be added to the magnifying glass to make the image more clear. 4, white acetate test to detect clinical and subclinical HPV infection: In addition to the detection of visible condyloma acuminata, both male and female, white acetate test can be used to detect subclinical HPV infection. Most cervical HPV infections in women are subclinical. Detection of subclinical HPV infection using the white acetate test at the vulvar site can determine the cause of recurrence. Subclinical HPV infection of the male external genitalia can cause small, non-tipped lesions that are not visible to the naked eye, particularly papules and patchy lesions. Screening for HPV infection, such as the HPV white acetate test, in high-risk male populations can also serve the purpose of preventing cervical cancer in women, as inconspicuous HPV infection in men often leads to potentially cancer-causing HPV infection in women. 5. False-positive white acetate test: Although the sensitivity of the white acetate test for detecting clinical and subclinical HPV infection is good, the specificity of this method is sometimes less than ideal, and false-positive reactions can occur in some chronic inflammatory conditions, such as urethritis and glans circumcision, epithelial thickening or abrasion trauma. The difference is that the whitening in a false-positive result appears ill-defined and irregular when compared to a true-positive result, and is sometimes not even apparent.