Multiple HPV infections raises cancer risk says study
Infection by multiple strains of the human papillomavirus (HPV) - the sexually transmitted disease which can cause cervical cancer - increases the risk of the disease, scientists have said.
Most strains of HPV are relatively harmless, but some may cause genital warts and others cervical cancer.
Scientists have found that some forms of HPV thought harmless may act in combination with others to cause the skin lesions that can develop into cancer, however.
"Women who harbour multiple infections are at higher risk for cervical lesions than those infected with one type only and should be followed more closely," said lead author and professor of epidemiology and oncology Dr Eduardo Franco.
The researchers added that the study pointed to targets for the next generation of treatments.
An HPV vaccine, which targets HPV 16 and 18, the two strains linked to the majority of cervical cancers, is currently being submitted to medical regulators around the world.
The vaccine does not target HPV 58 however, which the study found was similarly carcinogenic in combination with other strains. The researchers have also recommended that current cervical cancer screening, based on the smear test, should be replaced with a test able to reveal the number and types of HPV strains detected.
The study was conducted by the McGill University in Canada in collaboration with the Ludwig Institute for Cancer Research in Brazil.
It is published in the July issue of the journal Cancer Epidemiology, Biomarkers & Prevention.
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