Though more expensive, single use vaccines that are preservative-free made more sense than vaccines containing ethyl mercury.
But given the use of ethyl mercury, one would think that some precautions would be taken:
Since the merthiolate in vaccines is a pro-oxidant, and the oxidation reaction reduces glutathione, which via stimulation of the transsulfuration pathway, reduces methylation of key brain lipids, and thus disrupts gamma wave communication between regions of the brain, one would think that a sensibly formulated vaccine would contain high levels of injectable vitamin C and a reasonable dose of methylcobalamin.
Methylcobalamin allows regeneration of methionine from homocysteine, even when glutathione is reduced in concentration by oxidative stress (and is thus less able to activate the inactive and commonly supplemented forms of vitamin B12, hydroxycobalamin and cyanocobalamin).
The vitamin C will reduce the oxidative stress and keep glutathione levels higher (alpha lipoic acid as a supplement would help here as well) and the methylcobalamin will allow the regeneration of methionine from homocysteine even if glutathione levels are still reduced.
The vitamin C/methylcobalamin could be given as a separate injection. In this way, much more vitamin C could be added as a protectant. Failing that, I would think that -and this is clearly less desirable- doctors would at least recommend that vaccinees take high doses of vitamin C before and after the vaccine, and also lipoic acid and methylcobalamin.