London — A vaccine given to girls to protect them against a virus that causes cervical cancer is a “critical” health tool and access to it should be scaled up as soon as possible, especially in poorer countries, say cancer experts.

Figures from the World Health Organisation's International Agency for Research on Cancer (IARC) showed an estimated 570,000 new cases of cervical cancer were diagnosed worldwide in 2018, making it the fourth-most common cancer in women globally.

Every year, more than 310,000 women die of cervical cancer, the vast majority in poorer countries with low rates of immunisation rates against the human papillomavirus (HPV) that causes it.

In wealthy countries, some antivaccine campaigners are also persuading parents to refuse the shot for their children, leaving them at risk, IARC said.

“Unfounded rumours about HPV vaccines continue to unnecessarily delay or impede the scaling up of vaccination,” said  IARC director Elisabete Weiderpass. She said IARC was committed to fighting cervical cancer and "unequivocally confirms the efficacy and safety" of HPV shots.

Britain’s GSK makes an HPV vaccine called Cervarix, which targets two strains of the virus, while Merck makes a rival shot, Gardasil, which targets nine strains.

In a statement addressed to the WHO last week, the GAVI vaccines alliance  urged greater support for HPV shots, saying it aimed to immunise 40 million girls in poorer countries against HPV by 2020. This would avert an estimated 900,000 deaths, GAVI said.

IARC said reducing the cost of vaccines in poorer countries would play a vital role in increasing access to them. It said it was working with the generic drugmaker Serum Institute of India to develop an HPV shot that “could provide a high-quality alternative at a lower cost”.