Last updated date: 08-Oct-2021
Originally Written in English
Human papillomavirus (HPV) and cervical cancer. What is the relationship between these two?
According to the World Health Organization (WHO), the human papillomavirus (HPV) is the most common viral infection of the reproductive tract. Most sexually active women and men will come into contact and be infected at some point in their lives and some may be repeatedly infected. The peak time for acquiring infection for both women and men is shortly after becoming sexually active. HPV is sexually transmitted, but penetrative sex is not a requirement for transmission. Skin-to-skin genital contact is a common form of transmission.
There are many types of HPV of which many do not cause problems. HPV infections usually clear up without any intervention within a few months after acquisition, and about 90% clear within 2 years. A small proportion of infections with certain types of HPV can persist and progress to cervical cancer.
Cervical cancer is by far the most common HPV-related disease. Nearly all cases of cervical cancer can be attributable to HPV infection. It takes 15 to 20 years for cervical cancer to develop in women with normal immune systems but only 5 to 10 years in women with weakened or compromised immune systems. The infection with certain HPV types also causes a proportion of cancers of the anus, vulva, vagina, penis, and oropharynx, which are preventable using similar primary prevention strategies as those for cervical cancer.
Non-cancerous types of HPV (especially types 6 and 11) can cause genital warts and respiratory papillomatosis (a disease in which tumors grow in the air passages leading from the nose and mouth into the lungs). Although these conditions very rarely result in death, they may cause significant occurrence of disease. Genital warts are very common, highly infectious and affect sexual life negatively.
Worldwide, cervical cancer is the fourth most frequent cancer in women representing about 8% of all female cancer deaths. 85% of these deaths occur in less developed regions, but that could simply be a result of high-quality medical services available to the general population in those nations.
In many developed countries, campaigns are in place which enable girls to be vaccinated against HPV and women to get screened regularly. Screening allows pre-cancerous lesions to be identified at stages when they can easily be treated. Early treatment prevents up to 80% of cervical cancers in these countries.
In less developed countries, there is limited access to these preventative measures and cervical cancer is often not identified until it has further advanced and symptoms developed. In addition, access to treatment of such late-stage disease (for example, cancer surgery, radiotherapy, and chemotherapy) may be very limited, resulting in a higher rate of death from cervical cancer in these countries.
The high mortality rate from cervical cancer globally could be reduced by effective interventions inclusive of vaccinations, check-ups, and treatments.
There are currently three vaccines protecting against both HPV types 16 and 18, which are known to cause at least 70% of cervical cancers. The third vaccine protects against three additional oncogenic HPV types, which cause a further 20% of cervical cancers. Given that the vaccines which are only protecting against HPV types 16 and 18 also have some cross-protection against other less common HPV types which cause cervical cancer, WHO considers the three vaccines equally protective against cervical cancer. Two of the vaccines also protect against HPV types 6 and 11, which cause anogenital warts.
Clinical trials and post-marketing surveillance have shown that HPV vaccines are very safe and very effective in preventing infections with HPV infections. The vaccines work best if administered prior to exposure to HPV. Therefore, the WHO recommends vaccinating girls, aged between 9 and 14 years, prior to having started sexual activities. The vaccines cannot treat HPV infection or HPV-associated disease, such as cancer.
Some countries such as the United States have also started to vaccinate boys as the vaccination prevents genital cancers in males as well as females, and two available vaccines also prevent genital warts in males and females. The WHO recommends vaccination for girls aged between 9 and 14 years, as this is the most cost-effective public health measure against cervical cancer. However, HPV vaccination does not replace cervical cancer screening.
As the relationship between the HPV virus and cervical cancer is well established, the recommendation to get vaccinated should be considered for those who are concerned. If such vaccination is not readily available in your area, use CloudHospital as a resource you can trust to guide you to hospitals and clinics that do.