Here are some well-written articles on vaccinating and the theories behind it.
Vaccinating your Dog,
Vaccinating your Dog,1996, International Vaccination Newsletter
Vaccines - Are They Safe for Your Dog?, by Dr. Dee Blanco, DVM.
Vaccination Myths, by Alan Phillips. (Human related)
The Immune System and Disease Resistance, by Dr. W. Jean Dodds, DVM. (off site)
Are We Vaccinating Too Much?, by Dr. Elizabeth Colleran, D.V.M.
Vaccination Update., by Dr. Jean Hofve, D.V.M.
The Big Scam--Rabies Vaccination, by Dr. John Fudens, D.V.M.
The Dangers of Vaccinations, and the Advantages of Nosodes for Disease Prevention (off site) by Dr. Donna Starita Mehan
If you decide NOT to vaccinate, but you are still unsure about Parvo (it has been our experience that Filas are not likely to contract the other canine diseases - Distemper, Adenovirus, Influenza, Leptospirosis, Corona) here are a few ways to help your dog through it in the rare occasion that it contracts the Parvo virus.
A simple way to deal with Parvo, by Brooks Bradley.