A disease you cannot catch sounds impossible, and that broken rule is the hook. The image names smallpox over a photo that is hard to look away from. Naming it spoils nothing. It just moves the question from which disease to why.
How the packaging works
Title
The title makes a claim that breaks what everyone assumes about disease.
Thumbnail
The thumbnail names smallpox over an old photo that is hard to ignore.
Remix this
When your fact breaks a rule everyone assumes, put that clash in the title. You can reveal the subject in the image as long as the why stays inside the video.
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