Waterborne, abiotic and other indirectly transmitted (W.A.I.T.) infections are defined by the dynamics of free-living pathogens and environmental reservoirs

Miles D. Miller-Dickson; Victor A. Meszaros; Francis Baffour-Awuah; Salvador Almagro-Moreno; C. Brandon Ogbunugafor

A concept that has been the object of recent inquiry includes infections transmitted indirectly between hosts via a surface or reservoir intermediate-often abiotic-where the pathogen lives freely and independently of a host [10] - [27] , sometimes described as "sit and wait" infections [28] . Much of this research has concentrated on fomite, aerosol and airborne-transmitted viruses [10] , [11] , [13] , [14] , [16] , [19] , [22] and waterborne infections [12] , [17] , [23] , [26] , [29] - [33] . Other studies have focused on systems where pathogens are growing in the environment [18] , or have explored indirectly-transmitted infections in theoretical terms [21] , [24] . One framework for studying indirect, environmental transmission-the environmental infection transmission systems (E.I.T.S)-is engineered with explicit constraints that render its application necessarily narrow [15] . We offer that these prior treatments are individual examples of a general phenomenon that would benefit from a mathematical treatment that is both more rigorous and more broadly applicable. This new formalism should accommodate a widerrange of pathogens than have been previously considered and should emphasize how the environment can comprise multiple discrete dynamic entities (not unlike how host populations are often modeled).