Vaccine Care and Handling

"A lot of very smart people are not aware of how to properly handle vaccines," said Rocky Bigbie, DVM, MS, director of field veterinary services with Fort Dodge Animal Health, at the 2005 Western Veterinary Conference held Feb. 20-24 in Las Vegas, Nev.

"Temperature is important, and it is important to maintain records of serial numbers, etc.," Bigbie added. "It can't sit in storeroom and get up to 90°F, or sit on a back porch and freeze. Room temperature is OK, as the vaccine stays cool enough with short times at room temperature." The ideal temperature is closer to 45°F than 35°F, he reported.

Even a brief moment of freezing damages the vaccine by separating the antigen-adjuvant complex, and giving once-frozen vaccine can cause big reaction knots, he said. Keep a thermometer in the refrigerator and make sure you're not freezing vaccine. Vaccine that's barely frozen will have little floating crystals, but just holding it in your hand will melt them, then it doesn't look any different. Look at vaccine immediately upon taking it out of the refrigerator to check for freezing.

The vaccine should be shaken well to suspend sediment that has settled to the bottom. Without shaking it, some horses would get very little adjuvant and others, little antigen.

Another concern with vaccine quality is contamination. Bigbie stated that the (West Nile virus, WNV) Innovator vaccine includes a phenol red indicator that changes the vaccine's color from pink to yellow or tan as pH increases from 6.8-8.2. "This indicates contamination because the pH has changed because of something growing in that vial," he explained. "Vaccine that has turned yellow does not mean use it faster, it means STOP! Don't use vaccine that has changed color."

Bigbie also focused on myriad hot topics in equine veterinary medicine including WNV, influenza vaccines, compounding, and bioterrorism. For more, see

About the Author

Christy M. West

Christy West has a BS in Equine Science from the University of Kentucky, and an MS in Agricultural Journalism from the University of Wisconsin-Madison.

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