Rumors that Xi Jinping is seriously ill are spreading fast online, a negative sign for Beijing's image as it weighs a high-stakes trip to the US to meet Trump.

• Talk of Xi's failing health is flooding Chinese-language social media and news feeds.
• Analysts warn that a face-to-face meeting with Trump could expose any physical or political weakness on Xi's part.
• Beijing has not addressed the rumors, and silence from the top tends to feed more speculation.
• Any sign of a weakened Xi would raise questions about who really holds power in China and how stable its leadership is.

Outlook: Watch whether Xi actually travels to the US and how he looks in public; a cancelled or shortened trip would fuel the rumors further.