CHENNAI: In a significant boost to India’s recently launched HPV vaccination drive, a major clinical trial published in ‘The New England Journal of Medicine’ has confirmed that a single dose of the HPV vaccine is as effective as two or three doses in preventing strains that cause most cervical cancers.
In what could be a game-changer for cervical cancer prevention in India, the findings come at a significant time for the nation, which launched its own free, single-dose national HPV vaccination campaign very recently this year.
The study, which was led by researchers at the US National Cancer Institute, tracked over 20,330 young girls between the ages of 12-16 years in Costa Rica for five years. The results of the study proved to be a turning point for cervical cancer prevention as it highlighted that one dose of either the bivalent (targeting two main cancer-causing HPV types) or nonavalent (targeting nine types) vaccine was as efficient as two or three doses.
The vaccine effectiveness against persistent HPV types that are responsible for the majority of cervical cancers across the world was a remarkable 97% across all groups.
Explaining the virus and its various strains, obstetrician and gynaecologist Dr P Narmadha of the Women Wellness Clinic, said, “Cervical cancer is caused by HPV or Human Papillomavirus, a common sexually transmitted infection that has over 100 types. The high-risk types (16 and 18) cause 70-90% of cervical cancers. The vaccine works best if given before first exposure to the virus, which is why it is recommended for young women.”
Dr PV Anuradha, senior obstetrician and gynaecologist at Rainbow Children’s Hospital observed that the revelation was a milestone, especially for countries like India which stagger under the burden of a high number of cervical cancer cases. “Despite being available in India since 2008, takers for the vaccine are low as the two-dose regimen cost close to Rs 8,000. The study provides definitive evidence that a single dose of HPV vaccine provides adequate protection as opposed to the two doses that were considered the norm so far. In India, everyday nearly 6 women die due to cervical cancer, so these results will ensure that more people come into the circle of getting it,” she added.
Health experts noted that for India, which accounts for nearly one-fifth of the world’s cervical cancer burden, the recent discovery is nothing short of a lifeline.
The NEJM study breaks down the numbers in a simple manner and revealed that among the participants receiving the bivalent vaccine, the infection rate difference between one dose and two doses was a negligible -0.13 per 100 people. Similarly, for the nonavalent vaccine, it was 0.21 per 100 people.
The study further noted that across all the trial groups, the efficacy of a single dose was nearly 97% and the participants had significant protection against the HPV strains for a longer period during the follow-ups.
It may be recalled that merely three months ago, the Union government launched the nationwide HPV vaccination drive that aims to cover approximately 1.2 crore girls aged 14 years across the country. The vaccine is currently being provided free of cost at all government health facilities.
“As of now, those below the age of 20 are being administered single doses of the vaccine as recommended by the World Health Organization (WHO). Beyond that women are expected to take two doses. But the new study comes as a breakthrough which can really help us in reaching more women and expanding coverage,” noted Dr Narmadha.
What kind of impact could the results of the study have on India? Doctors noted that though the vaccine is free, the real battle lies in reaching every girl. While it could prove to be extremely difficult to track adolescents for a second shot six months later, the single dose schedule could ensure maximum protection
“Cutting the dose from two to one significantly reduces the procurement cost and simplifies the chain of storage and transportation required which would help the vaccine to reach remote villages. But before all that, it’s essential that more awareness is created among parents, schools and the community in general regarding the importance and need of the vaccine and where girls can avail it easily,” reiterated Dr Anuradha.
A report in the National Family Health Survey – 5 warned that in India currently, only less than 2% of eligible women aged 30-49 undergo regular screening. “There is still a lot of taboo about sexual health and hygiene in our country. Many women still do not go for regular health check ups and are hesitant to voice out about their vaginal health or related complications. It is imperative that women go for regular pap smear exams once they become sexually active,” added the doctor.
Additionally, health experts continued to urge the government to tackle vaccine hesitancy, which remains high in rural areas.
Why the results are important to India
Cervical cancer remains the second most common cancer among Indian women
India records an estimated 1.23 lakh new cases and approximately 80,000 deaths annually
One woman is dying every six minutes from cervical cancer that is largely preventable
India accounts for nearly one-fifth of the world’s cervical cancer burden
What is cervical cancer?
Cervical cancer is a disease where cells in the cervix — the lower, narrow part of the uterus that connects to the vagina — grow out of control. It is most often caused by a long-lasting infection with the human papillomavirus (HPV)
Risk factors
Early marriage
Early sexual activity
Multiple sexual partners
Poor genital hygiene
Smoking
Multiple pregnancies
Weakened immunity
Long-term use of oral contraceptives (5 years or more)
Symptoms
Abnormal vaginal bleeding
Pain and spotting after sex
Unusually heavy menstrual cycles
Changes in vaginal discharge