HPV Infection and HPV Types

There are plenty of evidences that showed Human Papilloma Virus (HPV) is the sole agent that cause cervical cancer. HPV infection is the most common sexually transmitted disease in the world. It is estimated that up to 50 - 80% of women will acquire HPV infection in their lifetime.  The woman can also get infected by a multiple HPV types at one time.  As the infection carry no symptom, most women often not aware that they have acquired the infection. 

To date, there are about 72 types of Human Papilloma Virus (HPV) identified. Not all HPV types but HPV 16, 18, 31, 33, 45, 52, 58 are oncogenic and associated with cervical cancer. Globally, almost 70 % of cervical cancers cases are caused by HPV 16 and 18 while another 30% are due to HPV 31, 33, 45, 52, and 58.  Hence, by vaccinating against HPV 16 and 18, over 70% of cervical cancer cases can be prevented.

Most women who acquired HPV infection cleared or recovered from it spontaneously without any treatment. Those who have persistent HPV infection may eventually develop cervical cancer over period of time. Infection with HPV 16 and 18 and other oncogenic type HPV are more likely to persist than infection with other low-risk HPV types. In younger women aged 15-25 years, almost 80% of HPV infection are transient but in older women, cervical HPV infection are more likely to persist.

Almost all HPV infection are acquired through sexual intercourse either through genital to genital, finger to genital or oral to genital contact. Condom used may help to reduced risk but not fully protective against contact with HPV infected male organ.

Hence, we can conclude that all women who are or have been sexually active are at risk of exposure to HPV infection at any time of their lifetime unless they and their sexual partner/spouse have a lifetime mutual monogamous relationship.

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