Evidence from recent years shows that the effectiveness of single-dose immunization schedules against this virus is comparable to that of two- or three-dose regimens, concludes a group of vaccine experts. The finding would facilitate the inoculation of girls and adolescents to protect them from cervical cancer.
The Strategic Advisory Group of Experts (SAGE) on immunization explained that evidence that has emerged in recent years reveals that single-dose regimens against human papillomavirus (HPV) provide protection against cervical cancer comparable to that of two- or three-dose regimens.
HPV, sexually transmitted, causes more than 95% of cervical cancer , which is the fourth most common type of cancer among women in the world. 90% of women who suffer from it live in low and middle income countries.
Cervical cancer is a preventable disease in almost all cases ; However, many women suffer from it and succumb to it due to unequal access to health services, including vaccines, said experts from the World Health Organization (WHO).
The president of the Expert Group explained that the human papillomavirus vaccine is highly effective in preventing the serotypes responsible for 70% of cervical cancer.
“The Group urges all countries to introduce HPV vaccines and to prioritize immunization of multiple age groups and older and missing girls,” said Dr. Alejando Cravioto.
UNICEF/Laurent Rusanganwa. A young woman from Rwanda receives her vaccine against the Human Papillomavirus while her classmates watch attentively.
More vaccines for more girls
The finding on the effectiveness of single-dose vaccines would allow more girls and women to receive immunization and be protected from cervical cancer and its consequences on their lives.
SAGE has repeatedly expressed concern about the slow introduction of the HPV vaccine into immunization programs and the low overall coverage in the population, especially in poorer countries.
The deputy director general of the WHO, Nothemba Simelela, expressed confidence that cervical cancer can be eliminated.
“In 2020, the Cervical Cancer Elimination Initiative was launched to address several challenges, including inequity in access to vaccines. This single-dose recommendation has the potential to get us faster to our goal of 90% of girls being vaccinated before age 15 by 2030,” she noted.
Despite this confidence, Simelela clarified that acceptance of the vaccine has been slow and that coverage in countries is much lower than the 90% target due to various factors, including supply challenges and costs related to delivery. of a two-dose regimen to older girls who are not normally part of childhood vaccination programs.
Additionally, the cost of vaccines is relatively high , especially for middle-income countries. In 2020 global coverage reached just 13%.
PAHO. The human papillomavirus vaccine is effective and safe.
Political compromise
In the opinion of Dr. Simelela, a political commitment is needed for equitable access to immunization.
The WHO stressed that the single-dose vaccine program is less expensive , requires fewer resources and is easier to administer.
It also facilitates the implementation of catch-up campaigns for multiple age groups, reduces challenges related to tracking girls for their second dose, and allows financial and human resources to be redirected to other health priorities.
The UN agency asserted that the adoption of single-dose schedules would change the prevention of cervical cancer since more doses would be available to reach more girls and save more lives.
Currently, the SAGE recommendation is to administer HPV immunization as follows:
- a one- or two-dose schedule for the primary target of girls aged 9 to 14 years
- a one- or two-dose schedule for young women ages 15 to 20
- two doses with an interval of six months for women over 21 years of age.
For immunocompromised women , such as those who carry the human immunodeficiency virus, the Group recommends three doses when possible. If there is no such availability, that group must receive at least two doses.
