Estimating the impact of the HPV vaccination program on cervical cancer incidence in Malaysia

Abstract

Cervical cancer remains a significant global health issue, ranking as the fourth most common cancer and cause of mortality among women. Many countries, including Malaysia, have implemented HPV vaccination programs. Malaysia initiated its school-based HPV vaccination program in 2010 to prevent cervical cancer among vaccinated women. This research aims to estimate the trend of cervical cancer incidence in Malaysia from 2020 to 2110 and to project the year when elimination, defined by the World Health Organization's target, could be achieved. We developed a Susceptible-Exposed-Infected-Recovered- Susceptible model to simulate the dynamic transmission of HPV and the progression of cervical cancer among Malaysian women aged 13 and above. We assumed a heterosexual population with uniform sexual activity, equal birth and death rates, and vaccine coverage above 85%, with HPV vaccine immunity waning at a constant rate. The model was calibrated in Berkeley Madonna (v10.1.5) to 1999–2009 incidence data by adjusting R0 and key progression rates to minimize RMSE, and validated against observed crude incidence from 2010–2016. HPV vaccine coverage data were obtained from the Ministry of Health Malaysia, population data from the Department of Statistics Malaysia, and parameters from published literature. We simulated five vaccination scenarios, varying vaccine coverage and efficacy, to project incidence over a 100-year horizon. Without vaccination, cervical cancer incidence remains constant at 5.4 cases per 100,000 women. The incidence is also static around 5.3 to 5.5 per 100,000 women observed under low coverage (30%) and efficacy (50%) scenarios. With moderate vaccination coverage 70% and vaccine efficacy of 80% led to minimal declines, reducing incidence only by 5.8% up to 2110. Under Malaysia's current national program, assuming 85% vaccination coverage and 95% vaccine efficacy, with ongoing cervical screening and treatment of precancerous and invasive cancer, the cervical cancer elimination threshold of fewer than 4 cases per 100,000 women is projected to be reached by 2055 based on crude incidence, and as early as 2050 based on the age- standardized rate. The interpretation of age-standardized rates is limited because ASR was estimated using linear regression, while the model itself is not age-structured. These results emphasize the critical role of sustained high vaccination coverage and efficacy in achieving cervical cancer elimination and are vital for long-term public health planning in Malaysia.