Why some HPV infections clear, some turn cancerous

Fauziya Lugogo, a nurse at the Kenyatta National Hospital /HANDOUT

Human Papillomavirus (HPV) is one of the most common sexually transmitted infections globally.

Although it often causes no symptoms, its impact on women’s health particularly in relation to cervical cancer is significant.

According to the World Health Organization (WHO), cervical cancer is the fourth most common cancer in women worldwide, with around 660,000 new cases and about 350,000 deaths each year.

Nearly all of these cancers are caused by persistent infection with high-risk types of HPV.

Women living with HIV are six times more likely to develop cervical cancer than those without HIV.

Fauziya Lugogo, a nurse at the Kenyatta National Hospital, says infection with HPV is extremely common.

Globally, at least 80 per cent of sexually active individuals are infected with HPV at some point in their lives.

In Kenya, cervical cancer is the second most common cancer among women, with an estimated 5,845 new cases and 3,600 deaths each year.

Despite such a heavy burden, most HPV infections do not lead to cancer.

In women with healthy immune systems, the virus typically clears on its own.

Research shows that more than 85 per cent of infections can become undetectable within about two years as the body’s immune system suppresses the virus.

This natural clearance means HPV often causes no lasting harm.

However, the risk of HPV persistence and progression to cancer grows when the immune system is weakened or other risk factors are present.

According to Lugogo, these include being immunocompromised such as those living with HIV, tobacco use, early initiation of sexual activity and having multiple sexual partners.

Men are often asymptomatic carriers of HPV. Because the virus spreads through skin-to-skin contact during sexual activity, an infected man may unknowingly transmit HPV to a partner.

This is one reason why HPV remains widespread despite being largely preventable.

Persistent HPV infection can cause changes in cervical cells over many years.

If these abnormal cells are not detected or treated early, they may develop into cervical cancer.

Persistent infection with high-risk HPV types is responsible for almost all (about 99.7 per cent) cervical cancers.

“The fact that most infections clear naturally doesn’t mean we should not be aware of it,” Lugogo says.

“Screening, vaccination and safe sexual practices are vital tools to stop the virus before it leads to cancer.”

HPV vaccination, particularly when given before sexual activity begins, dramatically reduces the chances of infection with the high-risk strains that cause most cervical cancers.

Understanding HPV its prevalence, how it spreads, and how it can be prevented is essential for individuals and communities aiming to reduce the burden of cervical cancer.