Every year, more than 500,000 women are diagnosed with cervical cancer and over 250,000 die from the disease. The Human Papilloma Virus (HPV) is now a well-established cause of cervical cancer and, globally, millions are infected with the virus.
The majority of these deaths occur in less developed nations and practically all cases are caused by a persistent HPV infection. Available vaccines, which include Cervarix, protect against two viruses: HPV 16 and 18, which are responsible for around 70 per cent of all cervical cancer cases.
Currently, in Spain, two doses are administered to female children aged 11 to 12 over a six-month period as part of the national vaccine calendar, though the vaccine is approved for females aged nine and above. It is important to administer the vaccine before children become sexually active.
Another vaccine, Gardasil, can also be given to male children, to prevent genital warts and related diseases such as anal cancer. Despite the fact that the World Health Organisation and various European and American health agencies have recommended the vaccine, however, it continues to be questioned, with some alleging that it has dangerous side-effects and others that it is inefficient.
What is the Human Papilloma Virus (HPV)?
This virus is passed by sexual contact (genital, anal and oral). Penetration is not necessary for contagion to take place; skin-to-skin contact is all that is required. There are over 150 different HPV types, of which at least 13 can cause cancer.
Other types which are non-cancerous can nevertheless cause genital warts and respiratory papillomatosis, which causes wart-like growths in the upper airways, resulting in airway obstruction or voice changes.
The virus sometimes causes no symptoms at all, yet it can persist and cause cancer. The HPV virus is actually the second leading cause of cancer, after tobacco (despite the fact that most types of HPV do not actually cause cancer).
What are the Symptoms of HPV?
The body’s own immunity normally defeats the virus before it creates warts, though when these do appear, they can do so in various areas, depending on the type of HPV involved (warts can be genital, common, plantar or flat).
HPV can cause cervical cancer, which shows no signs or symptoms in early stages. Over time, precancerous lesions can grow, so it is vital to have regular pap smear tests to detect pre-cancerous changes in the cervix.
Ask your gynecologist about how often you should have these tests (frequency will vary between three and five years depending on your age). Women over the age of 65 can generally stop having the tests done if they have had three normal pap smear tests in a row.
How Do the HPV Vaccines Work?
The vaccines work similarly to others (such as the meningitis-B vaccine). Proteins are taken from the surface of the virus, though none of the inner structure is included.
Once injected into the system, the body recognises the virus, subsequently generating antibodies against these proteins. The antibodies attack the virus when coming into contact with it, stopping it from entering cells.
Although the vaccines are currently claimed to have a 70 per cent efficiency rate, scientists are working on achieving 90 per cent protection. The effects of the virus last for 10 years, covering the greatest period of possible exposure to the virus.
As is the case with most vaccines, the HPV vaccines have attracted their share of criticism. Proponents note that there are 45 million female children who have been administered the vaccine, and side-effects described are minimal, including fever, nausea and dizziness.
There are claims however that link the vaccine with inducing comas or suffering paralysis. As with all vaccines taken voluntarily, it is advisable to undertake some extensive research before administration.
How to Prevent the HPV
The only way to be 100 per cent sure that one won’t contract the virus is via sexual abstinence. Condoms can significantly reduce the infection rate if worn at all times, though it is vital to remember that HPV is a skin-to-skin infection, so that even with physical protection, contagion is still possible. Having good health and a robust immune system are important factors in avoiding contracting cancer.
Words Marisa Cutillas