Didn’t seem to doesn’t necessarily mean it didn’t happen, it can be difficult to quantify. Most people don’t notice a lot of the constant large scale ecological devastation that does happen.

The real concern is that even if it was fine in one location, that can’t reliably be assumed to be the case for other ecosystems. This issue is really complicated, we’ve acted hastily in the past and done some insane lasting damage so I’d say it’s best to be careful.

All that said, even if I’m vegan and this whole thing makes me extremely uncomfortable, working to eradicate malaria is objectively good.