Many young women have begun to engage in sexual activity as early as the age of 14. To many, talking to children about sex and their bodies is still a taboo subject. But it is so important that young women understand what happens to their reproductive system once intercourse begins.
One such important thing to know is that once a you have had sex, you have been more than likely exposed to the Human Papilloma Virus, commonly known as HPV. With persistent infections of this virus, women are at a high risk of developing cervical cancer, anal cancer and vaginal cancer. Local gynae-oncologist, Dr Anthony Pottinger was interviewed on this topic. This is what he had to say.
?Q: What is HPV?
A: HPV is abbreviated for Human Papilloma Virus. HPV are called Papilloma viruses because some of the HPV types cause warts or papillomas, which are non-cancerous tumours. It is a sexually transmitted disease which attacks the squamous epithelial cells in the body–the flat cells that line the surface of the skin and mucous membranes. At least 50 per cent of sexually active women contract some form of HPV during their lifetime. HPV can cause cervical cancer and/or warts.
Q: Are there different types of HPV?
A: Since its discovery, (there have) been known to be at least 200 types of this virus existing. One hundred of these different types infect animals and 100 infect humans. Out of the 100 that infect humans, 30 can cause infections in the genital and anal region. Out of these 30, 15 are oncogenic–cancerous. Out of these that cause cancer, roughly 70 per cent of cervical cancer worldwide is due to infections of HPV 16 and HPV 18. HPV 45 and 31 make up another 10 per cent, HPV 33 35, 52 and 58 make up a following ten per cent. Of all the types mentioned, HPV 16 and HPV 18 call for more concern if one is diagnosed with either of the two.
Q: Does HPV have any common symptoms?
A: There is no one symptom that can help you to know whether you have been infected or not with the HPV virus. It should be assumed 100 per cent of sexually active people have been exposed to HPV. Most are infected when they first become sexually active. However the vast majority would clear the infection on their own but the immunity seems not to be life-long, hence most are reinfected. Over a lifetime, the immune system is at its zenith in adolescence. But, as people grow older, their immune system weakens and some individuals may reach a point where they can no longer clear the virus. These people end up with persistent infections which make them susceptible to cervical cancer, vaginal cancer, anal cancer, vulva cancer and 20 per cent of squamous cell cancers in the head and neck region." A matter of fact, the World Health Organisation (WHO) declared a few years ago that the necessary cause of cervical cancer is a persistent HPV infection with one of the oncogenic viruses. This means no one can get cervical cancer without a persistent HPV infection.
Q: How does one prevent contracting HPV?
A: You need to get a pap smear done. Since everyone should be assumed to be exposed to HPV once they have begun sexual activity and since there are no early signs or symptoms, sexually active women should have a pap smear done three years after their first sexual intercourse. If the first two or three annual pap smears are normal, then pap smear testing should be done on a three-yearly basis, even if the person becomes celibate. However, it should be noted that pap smears are only secondary prevention, as they can only pick up what's already there, eg cancer, before it becomes an invasive cancer. The reason being there are several problems associated with pap smear screening, such as only 10-12 per cent of women do their pap smear on a regular schedule, plus the false negative rate could be as high as 50 per cent and the sensitivity can be as low as 50 per cent. This means that a lot of women would be diagnosed with cervical cancer, even if they do their pap smears. Hence the future lies with the HPV vaccine–primary prevention.
Q: Is there a specific age to receive the vaccine?
A: The ideal age for a girl to receive an HPV vaccine is between the ages of ten and 12–before she becomes sexually active. However, if you have already been sexually active, you should still get vaccinated because most people would clear the infection but natural immunity does not protect against future infections. If someone who is already sexually active gets vaccinated, the antibody levels are much higher than one gets with a natural infection and this would protect against future infections. For women who have been diagnosed with cervical cancer, pre-cancer (CIN2 or 3) and those diagnosed with an invasive cancer, their immune systems have demonstrated they cannot clear the virus, hence it it is imperative that these people be vaccinated after they have been treated.
Q: How long does the HPV vaccine last?
A: It has not been determined how long the vaccine can last. But mathematical modeling indicates the antibody levels would be very high for at least 20 years, with the vaccines Cervarix and Gardasil.
