A suspected lab accident in the Siberian city of Irkutsk has released pneumonic plague, killing a researcher and putting hospitals under forced quarantine — bad news for the region and a warning sign for everyone else.

• Russia first reacted hard, with security services moving people to hospitals, then flipped to denying the whole thing.
• Plague that starts in the lungs is very rare in nature, which raises the possibility the strain was engineered.
• Untreated, this kind of plague kills everyone who gets it; caught within a day, antibiotics cut deaths to under a fifth — unless the bug was built to beat antibiotics.
• Local reporters have gone quiet and papers are now denying the quarantines, so the West is unlikely to learn much more.
• Russia appears not to have told the WHO, and neither the WHO nor the CDC has said anything.

Outlook: Natural plague usually burns out on its own, so the next few days of secondary infections — and whether cases turn up outside Siberia — will show whether this is contained or something far worse.