Image HPV in Electron MicroscopeThere are varieties of papilloma viruses, from those human papilloma viruses (HPV) form a group. There are at least 200 types of HPVs, amongst which about 100 are fully studied by the researchers. Broadly these form two large groups; those affect cells on skin surface and others, which affect such type of cells in the natural orifices like vagina, mouth and inside of penile skin etc. Some give rise to low risk lesions like skin warts and others high risk lesions having potential to turn into cancers, like cancer cervix.About 40 types are found in the genital tract. Low risk HPVs like 6 and 11 cause 90% of genital infection, whereas some high risk group of HPVs like 16 and 18 cause 10% of infections. Other HPVs those can cause cancer are, 31, 33, 35, 52, 58, 39, 45, 59, 56, 66 and 51. However, HPV 16 is responsible for 50% of cancers followed by HPV 18 in 7 to 20% in a study; scientists say.
At present at least two types of vaccine are available, one manufactured by GlaxoSmithKline (GSK) and other by Merck Vaccine. The vaccine by GSK has been developed from parts of two viruses, HPV 16 and 18, whereas that from Merck Vaccine is from HPVintraepithelial cancer (CIN); vulvar and vaginal intra-epithelial neoplasia; and genital warts. 16/18/6/11. Both are being sold in many countries, are very much effective in preventing cervical
Image via Wikipedia, A wartIt is expected that the antibody level so produced after vaccination may last at par, as seen in case of natural infection by HPV, to be around 10 years. It is also seen by researchers that there is some cross-protection from some other types of HPVs like 31, 45, 52 and 58 after immunization by these vaccines.
Protective effect of these vaccines in HIV infected persons is doubtful as well as in immune compromised patents.
Vaccines best works best in 9 to 12 years of pre-pubertal girls; but, can be extended up to 23 years of sexually inactive women, without antibody in the blood. This vaccine though has not been prescribed for boys, but can have potential benefit of prevention of genital warts; and seen to have good antibody status by the researchers.
This vaccination may have immense benefits in the long term in preventing as many as 80% of cervical cancers, 60% of vulval and 90% of anal cancers in women. There is likely to be major improvement for human health and well-being of women every-where.
