Murder rates are usually overestimated, while diseases and accidents are underrated. Due to availability bias thing that happen regularly are concerns, things that are superrare, but might kill many people if are ignored.
Also intentionality matters- actions which have intent behind them are more salient. This helps make murder seem more likely. I wonder if cultures that believe that diseases are caused by demons or spirits are more likely to overestimate the risk of disease? This might be hard to test because those cultures are going to be ones generally without modern medicine and have higher disease rates. Maybe look at religious groups that strongly believe that sin causes disease?
As everyone here knows, it would be a stupid idea to switch from airplanes to cars out of safety/terrorism concerns: Cars are a much more risky means of transportation than airplanes. But what other major risks are there that many people systematically undervalue or are not even consciously aware of?
The same can be asked for chances.