HPV vaccination key in tackling cervical cancer

The Human Papillomavirus (HPV) is a common virus that is associated with ano-genital cancer. Normally, people are infected with HPV if their genitals or mouths touch the genitals of someone infected with the virus. HPV can also be spread by close genital-to-genital touch.

HPV infection in the genitals can cause cancer of the cervix or vagina in women or cancer of the penis in men. Other types of HPV can cause genital warts in women and men. HPV infection also causes anal cancer and oral cancer in both women and men.

The most important HPV related disease is cervical cancer, which affects the neck of the womb and the growth of abnormal cells in the lining of the cervix. All women are at risk of cervical cancer and this disease occurs most often in women over the age of 30.

Globally, cervical cancer ranks as the fourth most frequently diagnosed cancer and the fourth leading cause of cancer death in women with an estimated 570,000 cases and 311,000 deaths in 2018 and yet it is a preventable disease. Cervical cancer is the leading cause of cancer mortality among women in sub-Saharan Africa (SSA), including in Kenya, where it is ranked as the second most frequent cancer among women with 5,250 new cases diagnosed and 3,268 lives lost in 2018, according to the Ministry of Health. The disease causes more deaths – at 12 percent of those diagnosed – than breast cancer, of which nine percent of those diagnosed die. In 2012, cervical cancer was responsible for 16.3 percent of all cancer deaths in women. Researchers estimate that given the current low rates of screening and treatment, the number of deaths from cervical cancer could almost double by 2025.

In Kenya, the worrying rise in cervical and penile cancers and deaths is due to lack of awareness, failure to screen people early enough for the diseases and late diagnosis.

The role of the HPV vaccine is to prevent serious or deadly infections. The vaccine work by preparing the body to fight the germs that cause the infections. The vaccine has been shown to significantly reduce the incidence of anogenital cancer and genital warts.

Additionally, the HPV vaccination may decrease the incidence of oropha-ryngeal cancer as well as the maternal transmittal of HPV to infants. The US Food and Drug Administration (FDA) has approved three vaccines that are effective at preventing HPV infection.

These vaccines cover 2, 4, or 9 HPV sero- types, respectively. The HPV vaccine is recommended for girls and boys aged between 11–12 years and can be given to females and males up to age 26 years. For girls and boys who receive their first dose of HPV vaccine before 15 years of age, only two doses are needed.

The HPV vaccine is very good at preventing the infections that are caused by the virus and more than 270 million doses of the vaccine have been distributed around the world since 2006.

Safety studies continue to show that HPV vaccination is very safe and effective. In a recent study published in the Lancet June 2019, that was looking at the population-level impact following the introduction of HPV vaccination programs, revealed data from 60 million individuals and up to 8 years post vaccination showed compelling evidence of the impact of the vaccine in the reduction of HPV infections of the cervix in girls and women and anogenital warts diagnosed in girls, women, boys and men.
The writer is Consultant gynaecologist, oncologist, Department of Obstetrics and Gynaecology, Aga Khan University Medical College East Africa.