![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgAIHMy_verrwpGP-qVMd3BpNu5CUMoBXw3216K3pbeLI84sUrZPWncmFQ7fNuTK9RvKr-t8y6FHJYrE9uqFJkNVOBAakzCDCEh4ISXsfR7ygW5iem3uAY7jovS2ysyTepmWzU8KTyIeZA8/s320/Polio+vaccine.jpg)
Photo: oral polio vaccine, one vial contain 20 doses.
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Polio vaccine
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Oral polio vaccine(type I, II, III) is used in Japan. The time for
vaccination is Spring and Autumn.
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Polio virus infection;
Incubation period: 7-21 days
Transmission: fecal-oral or oral-oral routes.
Symptoms:
i) low-grade fever and sore throat occurs in 4-8%
of infections.
ii) most infections in human are asymptomatic.
Limb paralysis occurs in approximately
1 /1,000~2,000 infections
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