Delivery of recombinant adenoviral vaccines to either the nasal or intestinal mucosa is an attractive vaccination strategy for many reasons. Vaccines administered in this manner will offer improved safety with respect to disease transmission and needle-stick injuries among health care workers, significant issues of concern in developing countries where the demand for many vaccines is high [55] . Mucosal administration of vaccines reduces the pain associated with vaccination, eliminates the need for specialized training programs for large vaccination campaigns and makes selfadministration of the vaccine possible. This route of administration may also significantly reduce systemic toxicity associated with recombinant adenovirus despite the fact that it has been shown that nasal immunization with recombinant adenovirus-based vaccines can facilitate translocation of the virus to the central nervous system [52] . Even though testing of other virus-based vaccines such as influenza have reported similar findings and are currently used in the clinic [56] , studies designed to fully assess the toxicological profile of adenovirus vaccine after nasal administration are also currently underway.