Adenoviruses are unusually stable to chemical or physical agents and adverse pH conditions, allowing for prolonged survival outside of the body and water. Adenoviruses are spread primarily via respiratory droplets, however they can also be spread by fecal routes. Research into the molecular mechanisms underlying adenoviral transmission provide empirical evidence in support of the hypothesis that cellular receptors for adenovirus and coxsackievirus (CARs) are needed to transport adenoviruses into certain naive/progenitor cell types.