Unverified rumors that Chinese leader Xi Jinping collapsed or suffered a stroke at the BRICS summit in India are spreading fast, and China's secrecy around leaders' health means nobody can confirm or deny them — a bad sign for anyone counting on stability in Beijing.

• What is confirmed: at the summit opening, India's Modi paused his speech and twice asked "Is it okay?", and Xi skipped the state dinner that night, with Foreign Minister Wang Yi filling in and officials blaming travel fatigue.
• What is not confirmed: anonymous accounts claim Xi fainted, refused local treatment so India would not learn about his health, and was flown to Beijing's 301 Military Hospital with a suspected stroke — but there is zero evidence, and Xi attended meetings normally the next day before flying home.
• The rumor still racked up hundreds of thousands of views within hours because China treats its leader's health as a state secret: state media will not report it, reporters cannot ask, and doctors will not talk.
• In a system where all power sits with one man and there is no transparent succession plan, even a cold can turn into coup talk.

Outlook: The Trump–Xi meeting set for September 24 will be the real test — whether Xi shows up and how steadily he walks will settle the question one way or the other.