They are kept track of very closely, but because there's still smallpox that exists on the planet, there is some concern that that could be obtained and used to develop a weapon.

并且科学家们仔细记录病毒的使用情况,但因为这星球上仍存在天花,就会有人担心,某些人会获得天花病毒,并将其制成武器

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