八喜妈，帮你查了查，这是一段可以解释的文字，说明频繁打防疫针的害处，

Some other potential problems are more serious. One of the biggest worries is that frequent stimulation of the immune system can increase the risk of “immune-mediated diseases”. These are diseases caused when the body’s immune cells attack normal body cells. There is a theory that in rare cases, over-vaccination can over-stimulate immune cells, which go haywire and start attacking everything, including normal body cells. Keep in mind that there are many causes of immune-mediated diseases. 

http://www.i-love-dogs.com/forums/dog-health-nutrition/32765-aware-what-can-happen-too-much-vaccinations.html

但是以上信息并不是来自于权威的网站，只能让你了解过于频繁的防疫针会引来什么后果。注射疫苗现在已经称为了一个有争议的话题，World Small Animal Veterinary Association这个组织从2010年开始考虑减少犬类核心疫苗的种类和注射频率。

听听你的Vet怎么说吧。密切观察Punia

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