HPV Unveiled Prevention & Awareness: know it to avoid it
Many people have heard of it, but not everyone knows about HPV. Yet thanks to vaccination, which is available for boys and girls, almost eight thousand cases of cancer could be avoided each year in Italy. HPV-caused cancers are complicated and can affect the uterus, anus, vagina, vulva, penis, oral cavity, pharynx, and larynx. These could decrease significantly by getting vaccinated against the Papillomavirus (HPV), which is the main culprit.
For this reason, Humanitas University recently organised the ‘HPV Unveiled Prevention & Awareness’ event to provide correct and timely information to the around three hundred students from Hunimed and two V classes from the Italo Calvino Scientific High School in Rozzano who attended it. It was an intense morning, filled with notions and insights for everyone, especially for the youngest.
‘Most HPVs cause lesions such as warts on the skin or condylomata, which are excrescences of variable size that appear in the genital areas of both men and women, and which are usually benign. There are, however, oncogenic strains of HPV (such as HPV 16 and 18) that can promote the onset of tumours,’ explains Nicoletta Di Simone, Full Professor of Gynaecology and Obstetrics at Humanitas University. ‘Oncogenic strains of HPV are responsible for almost all cervical cancers and cancers affecting the female and male genitals: the vagina and vulva, the penis, the anal region or extra-genital cancers, i.e., cancers of the oral cavity, larynx and pharynx’.
Men are not immune. The infection in fact causes either benign or cancerous lesions affecting the genital, anal or oropharyngeal area.
‘In men it is mostly asymptomatic, and sometimes it is associated with the presence of condylomata, growths of tissue affecting the penile area, foreskin, glans, and anal region. In these cases, it is necessary to have a specialist urological assessment to make a correct diagnosis through an objective examination associated with a careful evaluation of any symptoms,’ explains the expert. ’There are no screening tests spread throughout the territory for men as there are for women (HPV test/pap-test). The absence of mass screening further underlines the importance of HPV vaccination also in the male population. In fact, through male vaccination, the circulation of the virus is significantly reduced, and men are protected from cancers associated with the infection of certain HPV strains.
The primary form of prevention is vaccination, which is the most effective way to avoid HPV infection. ‘Lifestyle plays an important role in determining infection: occasional, risky intercourse as well as failure to use a condom,’ says the expert. Secondary prevention consists of Pap-tests and HPV tests, to detect the viral DNA of HPV types with a high oncogenic risk. The prevention policy in the Lombardy Region allows access to Pap-testing from the age of 25 to 29, every three years, and access to HPV testing from the age of 30 up to 64, every five years.
HPV, or human papillomavirus
HPV is a heterogeneous group of small DNA viruses which infect the skin and mucous membranes. Their life cycle is linked to that of the cells they infect. In fact, HPV can stimulate the division and growth of the infected cells through the production of two key proteins, E6 and E7, directly involved in the pathogenesis process.
‘Human papillomaviruses constitute a large and heterogeneous group of almost 200 different viral types, divided into two large groups,’ explains Valeria Cento, Associate Professor of Microbiology at Humanitas University. Some types, called ‘cutaneous’, infect only the cells of the surface squamous epithelia, generating common lesions such as warts and papilloma. The viral types called ‘mucous’, are more versatile and can infect both the cells of superficial epithelia and those lining our mucous membranes. The ‘mucous’ types can therefore generate both common skin lesions and more serious diseases such as cervical, anal, or oropharyngeal cancer. In such cases we are talking about ‘high-risk’ genotypes. Primary HPV infection is typically asymptomatic. ‘Once internalised, the HPV can “reprogram” the maturation of the host cell, to make its own survival and the production of new viral particles more effective,’ the expert continues. ‘Our immune system is extremely important for the control and resolution of HPV infection, which is generally achieved within a few months, generating a lifelong immune memory. However, HPV can suppress or evade protective immune responses, generating the lesions we know over time. High-risk HPV types can activate a particular mechanism of persistence and escape from the immune response, which ultimately makes these viruses associated with cancer development. A key element in this process is the integration of the HPV genome within the cellular DNA that makes up our chromosomes. The cell containing the integrated virus is stimulated by this to uncontrolled reproduction, and this increases, over time, the risk of one of these cells initiating a cancerous transformation process. Because of this mechanism of pathogenesis, HPV is classified as an oncogenic virus’.
HPV vaccination
HPV vaccination is recommended because it provides effective protection against the HPV strains responsible for more than 70% of cervical cancers and other related oncological diseases, such as oropharyngeal and anal cancers.
Vaccinating young people before the onset of sexual activity reduces the circulation of the virus in the population and prevents the occurrence of HPV-related neoplasms. Since 2009, the HPV vaccination has been offered in the Lombardy Region to everyone – females and males – between 11-12 years of age, but it can be administered as early as 9 years of age if a child needs to leave the country for a long stay before the age of 12. Two doses of the vaccine are given by the age of 14 and three for those who start vaccination from the age of 15. It is also possible to complete the vaccination cycle up to the age of 26 for those who were not vaccinated during adolescence, while administration for adults over the age of 26 is considered only in the presence of specific risk factors. Optimal protection against the virus is reached approximately two weeks after the last dose. To date, it is not yet possible to establish with certainty how long this protection will last, since vaccination was introduced relatively recently in Italy.
‘Achieving a high vaccination coverage in the population is crucial to ensure effective protection against the virus at community level. Scientific evidence shows that an HPV vaccination coverage which is higher than 90 per cent reduces the circulation of the virus and the risk of infection not only among the vaccinated but also among the unvaccinated, thus favouring the so-called herd immunity – informs Elena Azzolini – Associate Professor of General and Applied Hygiene and Preventive Medicine at Humanitas University -’. Moreover, the vaccine has been shown to reduce the risk of recurrence in people already suffering from HPV-related lesions, including those with a high frequency of recurrence such as ano-genital condylomas. – She continues, ‘We need to overcome barriers such as vaccination scepticism, unequal access and cultural differences that limit the adherence to vaccination. Despite the proven effectiveness of this preventive measure, in Italy, HPV vaccination coverage in 11-year-old girls and boys is still far from the goal of immunising at least 90 per cent of the target population of girls and boys. Wide vaccination coverage allows to extend the benefits of prevention to the entire population, with positive effects not only in terms of public health, but also on a social and economic level, reducing healthcare costs and the number of deaths attributed to this virus’.
HPV prevention is a pillar of public health strategies. At a global level, the World Health Organisation (WHO) has launched the ‘HPV Free’ strategy, with the goal of eliminating all cancers caused by the Papilloma Virus by 2030, through three main targets: vaccinating 90 per cent of girls by the age of 15, ensuring 70 per cent coverage for screening of women at the age of 35 and 45, and to ensure that 90 per cent of women with pre-cancerous lesions receive appropriate treatment.