Definitely. And in in the last two weeks, the worlds largest bee that was thought to be extinct was found again in Indonesia. Particularly good news given the global decline of many bee species. [1]

And a type of tortoise thought to be extinct was seen for the first time in 106 years. [2]

1.https://www.upi.com/Science_News/2019/02/21/Worlds-biggest-b...

2. https://abcnews.go.com/US/video/tortoise-thought-extinct-dis...

Small pox! Yeaahhh!!

Beware! You entered the "cutesy animals, let's save the planet, everyone's cool man" territory with nuance, humour and wider perspective. People don't forgive that easily.

If you want to be fun at parties, you can also try this: "What do you mean, 'YOLO, do what your heart tells you, no matter what they say'? Does that also apply to rapists and murderers?"

I'll make an exception for infectious diseases... certainly getting rid of smallpox was, and eventually getting rid of HIV will be, a cause for celebration.