[Human papillomavirus type 18 - In memoriam].

Area of Science:

• Oncology
• Virology
• Public Health

Background:

• Human Papillomavirus (HPV) is a major cause of cervical cancer, with HPV 18 responsible for 19% of cases in Sweden, particularly adenocarcinomas.
• High vaccination coverage is essential for eliminating oncogenic HPV types (e.g., HPV 16, 18) and medium-oncogenic types (e.g., HPV 31, 33, 45, 52, 58).

Purpose of the Study:

• To assess the impact of HPV vaccination strategies on cervical cancer elimination.
• To determine the required vaccination coverage for eliminating specific HPV types.

Main Methods:

• Analysis of HPV vaccination coverage data in Sweden for women born 1994-1998.
• Evaluation of the effectiveness of current and proposed HPV vaccination programs.

Main Results:

• Catch-up vaccination against HPV 16 and 18 for women born 1994-1998 had only 55% participation, insufficient for virus elimination.
• Achieving approximately 70% participation in vaccination against HPV types 16, 18, 31, 33, 45, 52, and 58 is projected to eliminate medium-oncogenic types and establish population immunity for HPV 16/18.
• A national project offering free vaccines and screening since 2021 has shown a significant reduction in HPV 18 cases in highly vaccinated groups.

Conclusions:

• Expanding HPV vaccination to include a broader range of oncogenic types and increasing participation are critical for cervical cancer prevention.
• The ongoing national project shows promising early results for HPV elimination, indicating the potential for imminent extinction of HPV 18.