脊髓灰质炎（poliomyelitis，简称polio）又称小儿麻痹（infantile paralysis）是由脊髓灰质炎病毒（poliovirus）引起的急性传染病，主要通过粪口途径传播。这个病由于大家比较熟悉，病本身就不仔细介绍了。脊髓灰质炎病毒包括三种血清型：PV1, PV2, 和PV3。由于这种病有比较严重的后果，所以其疫苗的必要性就不必介绍了。
关于脊髓灰质炎疫苗的伟大成就，我就直接摘抄wiki的原文了：
While now rare in the Western world, polio is still endemic to South Asia and Nigeria. Following the widespread use of poliovirus vaccine in the mid-1950s, the incidence of poliomyelitis declined dramatically in many industrialized countries. A global effort to eradicate polio began in 1988, led by the World Health Organization, UNICEF, and The Rotary Foundation. These efforts have reduced the number of annual diagnosed cases by 99%; from an estimated 350,000 cases in 1988 to a low of 483 cases in 2001, after which it has remained at a level of about 1,000 cases per year (1,606 in 2009). Polio is one of only two diseases currently the subject of a global eradication program, the other being Guinea worm disease. If the global Polio Eradication initiative is successful before that for Guinea worm or any other disease, this would be only the second time mankind has ever completely eradicated a disease. The first such disease was smallpox, which was officially eradicated in 1979. A number of eradication milestones have already been reached, and several regions of the world have been certified polio-free. The Americas were declared polio-free in 1994. In 2000 polio was officially eliminated in 36 Western Pacific countries, including China and Australia. Europe was declared polio-free in 2002. As of 2006, polio remains endemic in only four countries: Nigeria, India (specifically Uttar Pradesh and Bihar), Pakistan, and Afghanistan. （http://en.wikipedia.org/wiki/Poliomyelitis）简单来说，就是美国在1994年，包括中国在内的36个太平洋国家在2000年，欧洲在2002年都宣布彻底消灭了脊髓灰质炎。目前仅有4个国家有脊髓灰质炎流行：尼日利亚，印度，巴基斯坦和阿富汗（汗。。。怎么都跟咱中国边上啊？？？）。再加把劲人类就又一次消灭一种曾经危害全世界的传染病了。不过在这之前大家还是要打疫苗。希望用不了多久就不需要了。
CDC建议的免疫计划是2，4，6-18个月，加上4-6岁加强一次。
这个疫苗有两种，一个是口服的，称为OPV（oral poliovirus vaccine）；一个是打针的，称为IPV（inactivated poliovirus vaccine）。
其中OPV是减毒活疫苗，由于这种疫苗价钱比较便宜，另外这种疫苗是口服的活疫苗，可以产生有效的胃肠道保护（应该是IgA反应），也有利于防止病毒的传播。因此在很多国家这种口服疫苗仍然是主要使用的疫苗。但是由于是减毒活病毒，在极少数接种的人真的会引起感染，因此在已经宣布消灭脊髓灰质炎的国家一般推荐使用IPV，就是灭活疫苗。
灭活疫苗由于是注射的，所以不能产生消化道免疫，只能防止病毒产生的神经毒引起神经系统损伤。目前在美国由于没有脊髓灰质炎，所以只使用IPV，而不再使用OPV疫苗。
据称，咱们国内虽然已经消灭了脊髓灰质炎，但是仍在使用OPV，我想主要原因可能是咱们离那几个流行国太近了，IPV不能阻止传播，所以只能继续用OPV。
http://en.wikipedia.org/wiki/Polio_vaccine
http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-ipv.pdf
美国的IPV由Sanofi-Pasteur生产，仅此一家，别无分号。这是一种灭活疫苗，所以没有传播或者感染风险。http://www.fda.gov/downloads/biologicsbloodvaccines/vaccines/approvedproducts/ucm133479.pdf
主要副作用好像除了局部的红肿之外，几乎没有。当然仍然有人可能过敏，跟其他疫苗一样。http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-IPV.pdf
No comments:
Post a Comment