The contaminants aren't breaking down in the body, and they could be making their way to tissues and organs and causing chronic inflammation. Recently reported reactions—from fever, epilepsy, speech loss, muscle pain, walking problems and hypersensitivity—could all be explained by contamination.

Scientists at the National Council of Research in Italy tested 44 routine vaccines—which included the MMR (measles-mumps-rubella), the HPV (human papilloma virus), several flu vaccines, and the DTP (diphtheria-tetanus-pertussis)—and discovered that all of them had some contamination, and several had up to 20 foreign particles.

The contaminations were discovered by using sensing equipment that was far more sensitive than anything used in quality control checks at the manufacturing plants.

The scientists say they were baffled by their discovery, and assume that the contamination must be happening somewhere along the production cycle.

The contaminants are being carried around the body in the bloodstream, so it can be hit-or-miss whether they cause a reaction in the individual, depending on where in the body they eventually settle. Even if there is no obvious reaction, the particles could persist in the body for a very long time because they are not bio-degradable.

The researchers accept that the drug companies responsible for the vaccines are not aware of the contamination, and this could explain why so many reactions are not appearing on the vaccine information sheets.