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 swiftly as possible, especially in poorer countries, Reuters Health reports cancer experts have said.
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. The report says each year, more than 310,000 women die from cervical cancer, and the vast majority of deaths are in poorer countries where immunisation rates against the human papillomavirus (HPV) that causes it are low.
In wealthy countries, some anti-vaccine 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,” IARC’s director Elisabete Weiderpass is quoted in the report as saying. She said IARC was committed to fighting cervical cancer and “unequivocally confirms the efficacy and safety” of HPV shots.
The report says 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 four strains.
In a separate statement recently addressed to the WHO, the GAVI Vaccines Alliance also urged greater support for HPV shots, saying it aimed to immunise 40m girls in poorer countries against HPV by 2020. This would avert an estimated 900,000 deaths, GAVI said.
IARC said in the report that 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”.
Wits RHI is the successful recipient of two awards from the Bill and Melinda Gates Foundation and the National Health and Medical Research Council of Australia for over the next five years, which will fund a study to evaluate the impact of 2-dose and 1-dose human papillomavirus vaccination schedules on community level HPV prevalence in South African adolescent girls.
Cervical cancer is caused by human papillomavirus (HPV)1 and is the leading cancer among women aged 15–442. In 2014, the National Health Department introduced HPV vaccination as a central strategy for cervical cancer prevention in South Africa. The current vaccine schedule requires administration of two doses.
However, there are a number of barriers to the administration of the second dose in particular, and there is growing interest in the potential of a single dose of HPV vaccine to provide enough protection.
The results of this study will have important implications for future programming; if a single dose is as effective as two doses in preventing HPV infection this may translate into increased cost savings and improved vaccine coverage which ultimately lead to better cervical cancer prevention and control.
In February and March 2019, the research team will conduct an HPV vaccine catch up campaign using a single dose of HPV vaccine in a population of adolescent girls in Grade 10 in Lejweleputswa District of the Free State, who would have been too old to receive the vaccine in 2014 when it was introduced. To evaluate the impact of the HPV vaccine in reducing HPV infection, the team will establish a network of eight sentinel surveillance sites.
These will include five primary health care clinics in Lejweleputswa and three others in Gauteng, Mpumalanga and North West provinces. The team will conduct a series of HPV prevalence surveys in 2019, 2021 and 2023 in these clinics among women aged 17-18 years attending family planning services.
Through these repeated surveys, the team will measure changes in the prevalence of HPV infection in age cohorts that were not eligible for vaccination compared to those that were, and received either one or two doses of vaccine. The project is led by Professor Sinead Delany-Moretlwe. The final study results are anticipated in the first quarter of 2024.
[link url="https://www.reuters.com/article/us-health-cancer-cervical/who-and-vaccine-group-back-critical-cervical-cancer-shots-idUSKCN1PT08H"]Reuters Health report[/link]