Put a thick amount of sunscreen on all areas of skin exposed to the sun.

VOA: special.2010.07.06

There are even some military personnel now who get immunized against smallpox in the event that when they're going into areas, they might be exposed when they're in combat areas.

现在有些军人甚至已经接种天花疫苗,以使他们在战场上,免受天花病毒的威胁

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