A groundbreaking study from Karolinska Institutet has revealed that fewer doses of the HPV vaccine may be sufficient to protect against cervical cancer, potentially transforming global vaccination strategies. The research, published in The Lancet Regional Health - Europe, analyzed data from over 2.2 million Swedish girls and women over a 17-year period.
Key Study Findings and Implications
The comprehensive analysis demonstrated that individuals who received one or two doses of the HPV vaccine before age 17 achieved protection levels against severe cervical changes comparable to those who completed the standard three-dose schedule. This finding holds particular significance for global public health initiatives, especially in regions where vaccine accessibility remains challenging.
"Our results support the recommendations from the World Health Organization (WHO) that one or two doses could be sufficient to protect girls and young women against cervical cancer," states Shiqiang Wu, research assistant at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.
Study Design and Methodology
The research team analyzed Swedish national registry data spanning from 2006 to 2022, examining vaccination records and the occurrence of high-grade cervical lesions in women aged 10-35 years. To ensure robust findings, researchers controlled for potential confounding factors, including socioeconomic background and maternal history of severe cervical changes.
Global Health Impact
Cervical cancer ranks as the fourth most common cancer among women globally, claiming over 340,000 lives in 2020. The WHO's ambitious goal to eliminate cervical cancer as a public health concern by the century's end includes achieving 90% vaccination coverage among girls before age 15.
"Our findings strengthen the evidence that one or two doses of the HPV vaccine may be sufficient, which could help vaccinate more girls and accelerate efforts to eliminate cervical cancer," explains Jiayao Lei, assistant professor at Karolinska Institutet.
Future Research Directions
While the results are promising, the research team emphasizes the need for continued investigation. "The next step is to follow those who received fewer than three doses over a longer period to ensure continued protection against cervical cancer and to study the effects of the new 9-valent vaccine," notes Lei.
This research breakthrough could particularly benefit low- and middle-income countries, where cervical cancer burden is highest and vaccine accessibility remains a significant challenge. The potential for reduced dosing schedules could lead to more cost-effective and widely accessible vaccination programs worldwide.
