http://www.vet.purdue.edu/epi/CoverLetter-PurdueUniversityGreatDaneHealthandVaccineStudy-new.pdf
www.vet.purdue.edu/epi/gdhstudy.htm If your friend is interested in this subject there is rheams of new information on the web..... I have now gone to homeopathic flu vaccinations for myself and my husband and no or few vaccinations for myu dogs.
Thank you