Why was smallpox an ideal candidate for eradication?

Smallpox was a suitable candidate for eradication for several reasons . Its distinctive rashes may be developed and survivors gained lifetime immunity.

Smallpox cases could be identified because smallpox is a clinically evident (clear) disease and there is no subclinical illness.

The disease moves relatively slowly transmission does not occur during prodrome and maximum transmission is at the time.

Smallpox was caused by a variola virus and was transmitted between people through the air. It was usually spread by face-to-face contact with an infected person and  contaminated clothes and bedding , so there were no reservoir.

In 1980, the world health assembly declared smallpox eradicated and no cases of naturally occurring smallpox have happened since .