An Argument for Individual Contribution to Herd Immunity
Last week, Dr Pauline Chen wrote a compelling editorial linking dog poop and the measles outbreak in the US. Strange bedfellows, you think? Her point is that just as cleaning up after your dog is an act of personal commitment toward a healthier community, so is vaccinating your children against measles. Since the 1960s, we have depended upon ‘herd’ or community immunity to fend off this dangerous disease. By vaccinating 95% of our children, we have created herd immunity, which protected nearly 100%, including those too young, ill or compromised to be vaccinated themselves.
However, in recent years, quackery defeated decades of community immunity. A misplaced fear of autism has caused enough parents to stop vaccinating their children that the safety net has been compromised, resulting in 500 cases of measles this year alone.
So what does this have to do with dogs? Dog owners may be facing a similar break in herd immunity. Although parvo hadn’t been eradicated to the same extent as measles, occurrences were primarily limited to unvaccinated dogs brought into shelters. Since the vast majority of owned dogs were vaccinated, herd immunity protected well cared for non-responders (those genetically unable to respond to the vaccine), immune-compromised and very young dogs.