Lodmell Donald L, Ewalt Larry C, Parnell Michael J, Rupprecht Charles E, Hanlon Cathleen A
Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, 903 South Fourth Street, Hamilton, MT 59840, USA.
Vaccine. 2006 Jan 23;24(4):412-6. doi: 10.1016/j.vaccine.2005.08.003. Epub 2005 Aug 15.
Rabid dog exposures result in > 99% of human rabies deaths worldwide. Ninety-eight percent of these cases occur in developing countries. Thus, the best protection against human rabies would be prevention through adequate vaccination of the reservoir population. The difficulty in re-locating ownerless, freely roaming dogs for booster vaccinations, in addition to poor coverage with inadequate vaccines, suggests that a potentially inexpensive vaccine that elicits long-term protection after a single-dose could improve control of canine rabies in developing countries. One solution could be a DNA vaccine. We have previously determined that dogs vaccinated intradermally (i.d.) in ear pinnae with a rabies DNA vaccine expressing a rabies virus glycoprotein (G) produce high levels of neutralizing antibody that persist for at least 6 months. In the present study, we determined whether a one-time i.d. rabies DNA vaccination into ear pinnae 1 year before viral challenge would protect dogs against rabies virus. The dogs did not receive a booster vaccination. All dogs (100%) vaccinated i.d. in each ear pinna with 50 microg of rabies DNA vaccine, or intramuscular (i.m.) with a commercial canine rabies vaccine survived a lethal dose of rabies virus. In contrast, 100% of dogs vaccinated i.m. with 100 microg of rabies DNA developed rabies, as did 100% of negative control dogs that were vaccinated i.d. in each ear pinna or i.m. with DNA that did not express the rabies virus G. The data suggest that a one-time i.d. rabies DNA vaccination into ear pinnae offers a new approach to facilitate control of endemic canine rabies in developing countries.
在全球范围内，感染狂犬病的狗的暴露导致了超过99%的人类狂犬病死亡。其中98%的病例发生在发展中国家。因此，预防人类狂犬病的最佳方法是通过对储存宿主群体进行充分的疫苗接种来实现预防。除了疫苗覆盖不足外，重新安置无主、自由游荡的狗进行加强疫苗接种也存在困难，这表明一种单次接种后能产生长期保护作用且可能价格低廉的疫苗，可能会改善发展中国家犬类狂犬病的防控情况。一种解决方案可能是DNA疫苗。我们之前已经确定，用表达狂犬病病毒糖蛋白（G）的狂犬病DNA疫苗皮内（i.d.）接种耳廓的狗会产生高水平的中和抗体，且至少持续6个月。在本研究中，我们确定在病毒攻击前1年对耳廓进行一次性皮内狂犬病DNA疫苗接种是否能保护狗免受狂犬病病毒感染。这些狗没有接受加强疫苗接种。所有在每个耳廓皮内接种50微克狂犬病DNA疫苗或肌肉注射（i.m.）商业犬用狂犬病疫苗的狗（100%），都在接受致死剂量的狂犬病病毒后存活下来。相比之下，100%肌肉注射100微克狂犬病DNA疫苗的狗患上了狂犬病，在每个耳廓皮内接种或肌肉注射不表达狂犬病病毒G的DNA的100%阴性对照狗也患上了狂犬病。数据表明，对耳廓进行一次性皮内狂犬病DNA疫苗接种为促进发展中国家地方性犬类狂犬病的控制提供了一种新方法。
