Impact of Early HPV Vaccination on Cervical Cancer Prevention: Insights from a Scottish Study

Sub: Sci

Sec: Health

Why in News

A recent population-based study conducted in Scotland has highlighted the effectiveness of early HPV vaccination in preventing cervical cancer. This research, covering data from 1988 to 2016, shows that women vaccinated at a young age have a significantly lower risk of developing cervical cancer.

Key Findings:

The study tracked women vaccinated with the bivalent HPV vaccine when they were 12-13 years old. It found no cervical cancer cases in this group.
The HPV immunization program in Scotland began in 2008, targeting young girls with routine vaccination.
Routine vaccination for girls aged 12-13 is highly effective in preventing invasive cervical cancer.
In the 14-18 age group, three doses of the vaccine significantly reduced the incidence of invasive cancer, although the protection was not absolute.
No cases of invasive cervical cancer have been reported in those vaccinated at 12-13 years.

About Human Papillomavirus (HPV):

It is a common virus with over 100 strains, some of which can lead to cervical cancer and other cancers, as well as genital warts. HPV types 16 and 18 are responsible for around 70% of cervical cancer cases worldwide.

About HPV Vaccine:

The HPV vaccine is designed to prevent infections from high-risk HPV strains linked to cancer. It works best when administered before exposure to the virus, ideally during pre-adolescence (ages 11-13).
“Valent” in HPV Vaccines: The term “valent” refers to the number of different HPV (Human Papillomavirus) strains a vaccine targets. Each type of HPV vaccine is designed to protect against specific strains known to cause cervical cancer and other HPV-related diseases.

Bivalent Vaccine

Targets: HPV types 16 and 18.
Coverage: Provides protection against the two strains responsible for about 70% of cervical cancer cases.
Example: Cervarix.

Cross-Protection of the Bivalent Vaccine:

The bivalent vaccine also offers cross-protection against HPV types 31, 33, and 45, expanding its effectiveness to approximately 85% of HPV-positive invasive cervical cancers.
This cross-protection is broader than that of the quadrivalent vaccine, though not as comprehensive as the nonavalent (nine-valent) vaccine.
Monitoring the emergence of other HPV types in vaccinated populations will be crucial to assess the long-term impact.

Quadrivalent Vaccine

Targets: HPV types 6, 11, 16, and 18.
Coverage: In addition to cervical cancer, it protects against strains causing genital warts (types 6 and 11).
Example: Gardasil.

Nonavalent (Nine-valent) Vaccine

Targets: HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58.
Coverage: Offers the broadest protection, covering about 90% of HPV-related cancers and diseases.
Example: Gardasil 9.

What is Cervical Cancer?

Cervical cancer develops in a woman’s cervix. It is the 4th most common type of cancer among women, globally and 2nd most common among women in India.
India contributes the largest share of the global cervical cancer burden; nearly 1 in every 4 deaths globally due to cervical cancer (as per The Lancet study).
Almost all cervical cancer cases (99%) are linked to infection with high-risk HPV, an extremely common virus transmitted through sexual contact.
Effective primary (HPV vaccination) and secondary prevention approaches (screening for and treating precancerous lesions) will prevent most cervical cancer cases.
When diagnosed, cervical cancer is one of the most successfully treatable forms of cancer, as long as it is detected early and managed effectively.
Cancers diagnosed in late stages can also be controlled with appropriate treatment and palliative care.
With a comprehensive approach to prevent, screen and treat, cervical cancer can be eliminated as a public health problem within a generation.