Human papillomaviruses – HPV – are a group of very common viruses. For most people, they do not cause serious problems or complications, but some types of human papillomavirus can cause genital warts or cancer.
The human papillomavirus infects the skin. There are over 100 different types.
How is the human papillomavirus spread? The risk of HPV infection is very high, about 80% of women become infected during sexual activity. The infection is transmitted exclusively through sexual contact. Using a condom reduces the risk but does not completely eliminate it.
Many types of papillomaviruses infect the mouth, throat, or genital area. Their reproduction is extremely simple.
Human papillomavirus infection can occur through:
- Any skin-to-skin contact in the genital area;
- vaginal, anal, or oral sex;
- Sex toy exchange
HPV infection is most often transient, asymptomatic, and causes no clinical problems. In 80% of cases, the body copes with the infection within 1 year, and in 90% within 2 years due to its cell-mediated immune response.
Despite the recovery, the primary infection with the virus does not proceed with the development of stable immunity, i.e. the woman is not protected from re-infection.
However, in about 20% of cases, the disease does not end spontaneously, but, on the contrary, gradually and slowly progresses from low to high cervical lesions to cervical cancer.
In untreated women, the time between infection and development of cervical cancer is usually 10 to 20 years.
The main risk factor for the disease is the number of sexual partners, especially with risky sexual behavior. Early sexual activity, as well as a weakened immune system, smoking, and poor intimate hygiene also increase the risk of infection.
As for the risk factors for the persistence of infection and the development of cervical cancer, these include:
- Type of HPV infection and oncogenicity of the virus;
- The immune status of the patient. People with a weakened immune system (eg, HIV patients) are more likely to develop persistent infections and more rapidly progress to malignancies.
- Co-infection with other sexually transmitted agents such as herpes simplex, chlamydia, and gonorrhea.
- Parity (number of births) and young age at first birth.
There are currently 3 certified vaccines, each of which protects against both HPV 16 and HPV 18, which are known to cause at least 70% of cervical cancers. The third vaccine protects against five additional oncogenic HPV types, which cause another 20% of cervical cancers.
The WHO considers that all three vaccines provide equal protection against cervical cancer. The two vaccines also protect against HPV types 6 and 11, which cause anogenital warts.
Clinical trials have shown that HPV vaccines are very safe and very effective in preventing HPV infections, high-grade precancerous lesions, and invasive cancer.
HPV vaccines work best if given before exposure to the virus. This is why the WHO recommends that girls be vaccinated between the ages of 9 and 14 when most of them have not yet started having sex.
Vaccines cannot treat HPV infection or HPV-related diseases such as cancer