Smallpox was a systemic disease, officially eradicated since 1979, caused by infection with the Variola major virus, whose only reservoir was infected humans.
Črne koze so bile sistemska bolezen, ki je uradno izkoreninjena od leta 1979. Povzročala jo je okužba z virusom Variola major, katere edini rezervoar so bili okuženi ljudje.