What is the HPV vaccine and how does it prevent cancer?

By Dr. Amit Chakraborty, M. S General Surgery and M. Ch. Oncosurgery

The Human papillomavirus (HPV) is a vast group of over 200 related viruses. Studies indicate that nearly 25% of these HPV are linked to direct sexual contact.  HPV is passed on by direct skin to skin contact during vaginal, anal or oral sex with someone who has been infected with HPV.  HPV ‘infection’ is very common and affects the majority of sexually active women and men and usually gets cleared from the body naturally. Sometimes HPV infections don’t clear from the body naturally and the infection becomes chronic or persistent. This advanced HPV is termed high risk HPV, which may develop into various types of cancers in men and women. These range from cervical cancer, vaginal cancer, vulval cancer, anal cancer, cancer of the penis, to some cancers of the head and neck

Thankfully today, our medical organisations are equipped with HPV vaccines which stimulate the body to produce antibodies that, in future encounters with HPV, bind to the virus and prevent it from infecting cells. According to the WHO, three HPV vaccines are marketed in many countries throughout the world – a bivalent, a quadrivalent, and a nonvalent vaccine. The vaccines are also found to be highly effective in preventing pre-cancerous cervical lesions caused by various HPVs. 

While breast cancer is the most common cancer among Indian women, Cervical cancer takes the second spot!

As per 2012, every year over 1 lakh Indian women are diagnosed with cervical cancer and more than sixty thousand succumb to it. In 2018, India recorded the highest estimated number of cervical cancer deaths, a research paper published in the Lancet Global Health revealed. The report further revealed that India contributed to 97,000 cases and 60,000 deaths. 

With wide availability of the HPV vaccine, it is believed that HPV-related cancers may become rare occurrences in the near future. HPV infections can be spread through any skin-to-skin contact, which essentially means the virus can spread during any kind of sexual activity, including touching. Therefore, it is commonly believed that the vaccine should be administered before the age at which any sexual activity may begin. Children and adults ages 9 through 45 years are advised to get the HPV vaccine. 

Notably, Dr Amit advises that people who have gotten the HPV vaccine still need regular testing for cervical cancer because the vaccines may not prevent all types of HPV that can cause cervical cancer. Further, there is no evidence that proves the HPV vaccine to be effective against other sexually-transmitted diseases like Chlamydia etc.