A Geographical Puzzle on HPV

Will Gardasil and other anti-cervical cancer vaccines be as effective around the globe as they are likely to be in the U.S. and Europe? That's the question I asked myself after sitting next to a gynecologist who has been doing some work in Guyana. (These serendipitous encounters are one of the best things about attending conferences.)

Dr. Rebecca Kightlinger of the University of Virginia Health System told me that she was surprised to learn that the high prevalence of cervical cancer she found in one section of Guyana was linked to the HPV-35 subtype. Of course in the U.S., the predominant cancer-causing HPV subtyes are HPV-16 and HPV-18, which are included in Gardasil.

If the HPV subtypes that cause cervical cancer are different throughout the world, however, that means different vaccine formulations will have to be used in different parts of the globe..

It may also mean that different vaccine formulations may need to be used for different ethnic groups, who may have migrated to new regions.

Something to ponder if you're trying to reduce the enormous death toll due to cervical cancer throughout the world. (Or if you're expecting Gardasil to be a global blockbuster.)