Explaining away, augmentation, and the assumption of independence

Imagine you are on a tropical island in which there are three types of mosquito (Reb, Mar, and Murb) that carry a certain disease, called Ling fever. For each mosquito type, there is a certain risk of being bitten by an infected mosquito, and a certain risk of contracting the disease when bitten. One day during a routine health check, it turns out that …