144 countries have introduced the HPV vaccine and over 60 countries have now included testing in their cervical screening programmes. (Representative Image)
Usually, vaccines require two to three doses to have a sustained level of antibody against infection. But the HPV (human papilloma virus) vaccine, which protects you from HPV infection that causes cervical cancer, is unique. “Even with a single dose of the vaccine, the antibody level remains high and sustained over many years,” says Dr Partha Basu, head of the Early Detection, Prevention, and Infections Branch at International Agency for Research on Cancer (IARC)
He is among the authors of a series of studies that are exploring the potential of a single-dose HPV vaccination in cervical cancer prevention, particularly in low- and middle-income countries with limited healthcare resources. The results were published in a special issue of the Journal of the National Cancer Institute Monographs and presented at the 36th International Papillomavirus Conference (IPVC 2024) in Edinburgh, UK. As a best practice in resource-scarce areas, this study could help in the WHO’s Cervical Cancer Elimination initiative.
What the study shows
Researchers demonstrated that the protection provided by a single dose of the quadrivalent vaccine against persistent infection with HPV types 16 and 18 – the types responsible for nearly 80 per cent of cervical cancers in low- and middle-income countries – is as effective as that from two or three doses of the vaccine, even 15 years after the first dose of the vaccine was administered.
“These findings indicate that single-dose vaccination offers effective, long-lasting protection against HPV infections and cervical pre-cancers, making it a viable, simpler, and more accessible option for at-risk populations,” says Dr Basu. “The sustained protection observed up to 15 years after a single dose, along with the cost savings from lower HPV positivity rates and a reduced need for colposcopy and treatment, should strongly encourage many more countries to adopt a single-dose strategy in their HPV vaccination programmes,” he adds.
What about India’s HPV targets?
In 2020, a total of 194 countries resolved to eliminate cervical cancer. Four years on, 144 countries have introduced the HPV vaccine and over 60 countries have now included testing in their cervical screening programmes. About 83 countries include surgical-care services for cervical cancer in health-benefit packages.
In India, the government had announced a nationwide vaccination programme to protect women and girls from cervical cancer. “However, India is yet to announce the introduction of the HPV vaccine in the national immunisation programme. This has to be addressed as more than 100,000 women get this cancer every year and 70 per cent of them are detected at a very late stage. Less than one-third of such women will live beyond five years. By delaying vaccination, we are pushing thousands of girls to a lifetime risk of cervical cancer. India should go ahead with its indigenously-developed vaccine,” suggests Dr Basu.
Anuradha Mascarenhas is a journalist with The Indian Express and is based in Pune. A senior editor, Anuradha writes on health, research developments in the field of science and environment and takes keen interest in covering women's issues. With a career spanning over 25 years, Anuradha has also led teams and often coordinated the edition.
... Read More