Polio (Poliomyelitis)
什么是Polio (Poliomyelitis)？
Polio (poliomyelitis) is an acute highly infectious viral disease which mainly affects young children. It is caused by three types of poliovirus, Types 1, 2, and 3. Poliovirus infection occurs in the gastrointestinal tract and spreads in a minority of cases to the nervous system.
Polio cases have decreased worldwide by over 99 percent since 1988 due to a global effort to eradicate the disease. In countries that report polio cases, roughly 70-80 percent of cases are less than 3 years of age and 80-90 percent of cases are less than 5 years of age.
如何获得Polio (Poliomyelitis)？
The virus responsible for polio is transmitted through contaminated food and water and multiplies in the intestine, from where it can invade the nervous system to cause paralysis. Many infected people show no symptoms but do continue to excrete the virus in their feces, potentially transmitting the infection to others.
易感性和抗性
Susceptibility to infection is universal, however, paralysis occurs in only about 1 percent of infections. Paralysis occurs more frequently in infected, non-immune adults than in non-immunised infants and young children. Type-specific immunity lasts for the patients’ entire lives. Second attacks are rare and result from infection with poliovirus of a different type.
症状是什么？
Many polio infections show no symptoms at all. When present, initial symptoms of polio include fever, fatigue, headache, vomiting, stiffness in the neck, and pain in the limbs. A small proportion of infections (one in 200) can cause paralysis (often permanent) in only a number of hours. Among those that experience paralysis, 5 to 10 percent die when their breathing muscles become immobilized.
预防措施
脊髓灰质炎无法治愈。它只能通过脊髓灰质炎疫苗进行预防，该疫苗在儿童早期曾多次接种。在未消除小儿麻痹症的地区旅行之前，请务必通过加强剂量使儿童接种疫苗保持最新。在这些地区避免污染的食物和水很重要。
处理
There is no known cure or treatment for polio. It can only be prevented through immunisation.
疫苗接种
它常见于哪里？
自1988年以来，全球一直努力通过广泛使用脊髓灰质炎疫苗接种来消除这一疾病。因此，2013年，世界上只有三个国家继续报告零星的脊髓灰质炎病例。这些国家是阿富汗、尼日利亚和巴基斯坦。有时，脊髓灰质炎病例被输入到已消除该疾病的国家，并且可能发生一些继发性病例。安哥拉、尼日尔、乍得、刚果民主共和国和苏丹南部都发生过此类案件。
最近，埃塞俄比亚、索马里和叙利亚爆发了小儿麻痹症。
