Daily Dose: Pneumonic plague questions, dementia cases set to double and the rising cost of a hospital stay

The World Health Organization says it still has few clear answers about the recent death of a worker at a Russian institute that researched plague. Hundreds of the worker's co-workers and close contacts are now in isolation, and there are reports that another worker may have pneumonia. Officials have not confirmed a cause of death, but the case is drawing new attention to pneumonic plague, a rare form of the disease that affects the lungs.