This is a potentially deadly condition in which the individual chambers of a heart beat out of phase with each other.

ECONOMIST: Model behaviour

However, one virus which may cause a problem is West Nile Virus, a potentially deadly condition which peaks in the US in August and September.

BBC: Houses submerged in water in New Orleans

My ailment is just another ambient backdrop now, another machine falling apart with no parts to replace the scrapped ones, another grim dispatch from the quadrants of the deadly dull but not yet quite deadly enough condition our condition is in.

NEWYORKER: Lostronaut

The Natural Condition can be, and often is, cold and deadly.

FORBES: The Black Death: Longing For The Good Old Days