Rich countries on course to eliminate cervical cancer
The path to wiping out cervical cancer looks increasingly clear – at least for high-income countries with strong uptake of the human papillomavirus (HPV) vaccine and cervical screening. That’s according to a new study by Canadian researchers who warn that low-income countries will be left behind without global efforts to step up prevention.
While Canada is forecast to eliminate cervical cancer by 2048, the gap with lower-income countries is widening. A paper published in The Lancet by a team from Université Laval and the CHU de Québec shows that these inequalities could skyrocket within a few decades. This would leave Canada, Australia and some European countries free of a devastating cancer while the disease continues to kill women in poorer regions of the world.
‘Currently, the incidence of cancer in lower-income countries is three times higher than in wealthier countries,’ says Prof Marc Brisson of the Université Laval’s Faculty of Medicine and a researcher at the CHU de Québec-Université Laval Research Center. ‘If HPV vaccination coverage remains the same, it could be 12 times higher by the end of the century. Compared to Canada, we’re even talking about 40 times higher.’
In 2020, the World Health Organization set three targets for eliminating cervical cancer (defined as achieving an incidence rate of less than 4 cases per 100,000 women). The strategy involves vaccinating 90% of girls before the age of 15, screening 70% of women, and treating 90% of precancerous lesions and cancers. The research team wanted to determine whether countries were on track with these goals. They found that several high-income countries are hitting the targets, with some going further by introducing vaccination for boys.
‘High-income countries like Canada are on the path to elimination, but that’s not the case for many countries with the highest incidence rates, which have low vaccination coverage and limited screening,’ says Dr Mélanie Drolet, an epidemiologist at the CHU de Québec-Université Laval Research Center. ‘The good news is that there are ways to catch up, but they will require significant investment from countries and international organisations.’
Among these measures, Prof Brisson highlights the availability of new, lower-cost vaccines on the market and the option of administering just one dose instead of two. This would help reduce costs and allow for the introduction of additional programmes such as vaccinating boys, which indirectly protects girls, or conducting catch-up campaigns for adolescents and young adults who did not receive the vaccine during pre-adolescence.
The research team modeled various scenarios to assess the impact of prevention strategies, ranging from the status quo, in which the widening of inequalities increases dramatically, to the full achievement of WHO targets.
The paper concludes that the best strategy for reducing inequalities between low- and high-income countries would be to combine the achievement of WHO targets with universal vaccination for girls and boys and the implementation of catch-up campaigns.
‘We could prevent nearly 37 million cases of cancer by the end of the century,’ says Prof Brisson. He acknowledges, however, that introducing large-scale screening can be difficult for many countries. In such cases, universal vaccination with catch-up campaigns would be a promising and accessible solution. It would enable the elimination of cervical cancer in the vast majority of countries without increasing screening, at a rate equivalent to the WHO targets.
