The recent measles outbreaks and a conversation with a new puppy owner in which she told me her breeder cautioned against a particular vaccination got me thinking.
Human measles is caused by the Measles morbillivirus; canine distemper is caused by Canine morbillivirus. Both are highly contagious, potentially severe, and can cause life-long neurological disease or death.
These viruses don’t just cause a runny nose and a rash, they can kill.
You wouldn’t know it by recent news reports, but measles was declared “eliminated” (an absence of continuous disease transmission for greater than 12 months) from the United States in 2000. Every U.S. measles outbreak since has been associated with unvaccinated populations and/or travelers returning from areas with active outbreaks.
The U.S. population has had access to an effective vaccination protocol for measles since 1968, when cases reported to the Centers for Disease Control dropped from just over half a million/year to a little more than 22,000. As of May 3, there have been 764 cases reported to the CDC so far in 2019. These cases have been reported in 23 states, including Michigan.
Similarly, a commercial canine distemper vaccine became available in 1950 and distemper-related deaths dramatically declined. Unfortunately, we’ll never come close to eliminating—and certainly not fully eradicating—canine distemper due to both the large unvaccinated stray dog population and the fact that Canine morbillivirus isn’t particular about which species it infects (e.g. coyote, fox, skunk, raccoon, etc.).
There’s evidence to suggest the domestic dog introduced canine distemper to wildlife populations. This may have contributed to the extinction of the Tasmanian tiger, the near-extinction of the black-footed ferret, and death in zoo populations of big cats, African wild dogs, Serengeti lions, and seals.
So what did I say to my new puppy owner?
I asked what her concerns were. I listened. I agreed that vaccines aren’t 100% effective at preventing disease and that some have side effects. There’s always the possibility of an adverse reaction—I do see the occasional lethargic kitten or puppy, or swollen muzzle or case of hives following a vaccine.
I also shared that many of the veterinary vaccines we have today are safer and “cleaner”. They’re much less likely to cause adverse reactions due to recombinant technology and smaller components that can effectively stimulate immunity without causing illness. (Learn more about Canine vaccine guidelines and Feline vaccine guidelines.)
This spring marks my 30th year as a practicing veterinarian. I’m one of those people who read the fine print and ask about the research behind new products and, despite financial enticements, I stopped using a particular brand of vaccine because the number of lethargic cats was too high for my comfort. I was also a mom who declined hepatitis vaccines for my hours-old newborns because they weren’t IV drug users. However, considering both the risks and benefits associated with vaccination, my daughters were vaccinated at appropriate times and so are my pets… because vaccines save lives.