Inactivation Kinetics and Replication Cycle Inhibition of Adenovirus by Monochloramine

Monochloramine is commonly used as a secondary disinfectant to maintain a residual in drinking water distribution systems in the United States. The mechanism by which waterborne viruses become inactivated by monochloramine remains widely unknown. A more fundamental understanding of how viruses become inactivated is necessary for better detection and control of viruses in drinking water. Human adenovirus (HAdV) is known to be the waterborne virus most resistant to monochloramine disinfection, and this study presents inactivation kinetics over a range of environmental conditions. Several steps in the HAdV replication cycle were investigated to determine which steps become inhibited by monochloramine disinfection. Interestingly, monochloramine-inactivated HAdV could bind to host cells, but genome replication and early and late mRNA transcription were inhibited. We conclude that monochloramine exposure inhibited a replication cycle event after binding but prior to early viral protein synthesis.