Comparative study of the kinetics and mechanisms of adenovirus and bacteriophage PR772 inactivation by disinfectants used for global safe drinking water

adenovirus;PR772;free chlorine;monochloramine;drinking water;disinfection

Moor, Aimee Marie

关键词: adenovirus;    PR772;    free chlorine;    monochloramine;    drinking water;    disinfection;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/90758/MOOR-DISSERTATION-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

With nearly a quarter of the global population consuming fecally contaminated water, waterborne pathogens can have a significant impact on public health. Human adenovirus (HAdV), is found globally in water sources and can cause a variety of illnesses including gastroenteritis, respiratory disease, and conjunctivitis. HAdV is of particular concern in drinking water because of its resistance to common disinfectants such as low-pressure ultraviolet light and monochloramine. The reason HAdV is so resistant to monochloramine yet so susceptible to free chlorine remains unknown.The main goal of this research was to gain a better understanding of the mechanisms of HAdV serotype 2 (HAdV-2) inactivation by drinking water disinfectants. This research achieved the following objectives: (1) Characterized bacteriophage PR772 inactivation kinetics over a range of environmental conditions for a variety of drinking water disinfectants, with an emphasis on chlorine, to determine if PR772 is a good surrogate for HAdV-2; (2) developed methods to quantitatively analyze stages of the HAdV-2 and PR772 replication cycles that are able to distinguish between untreated viruses, partially inactivated (~90%) viruses, and inactivated up to 99.99%; (3) determined what stages of the HAdV-2 and PR772 replication cycles became inhibited after free chlorine or monochloramine disinfection.This research elucidated that HAdV-2 inactivated up to 99.99% by free chlorine could still attach to host cell monolayers, but genome synthesis as well as late hexon mRNA and early E1A mRNA transcription were inhibited. When exposed to free chlorine, PR772 had remarkably similar inactivation kinetics compared to HAdV-2. Like HAdV-2, free chlorine inactivated PR772 could still bind to host cells but genome replication and mRNA transcription were inhibited. Similar results were obtained for viruses inactivated by monochloramine, but the kinetics of inactivation for the two viruses were orders of magnitude different. Overall, exposure to chlorine-based disinfectants interfered with HAdV-2 and PR772 replication cycle events that occurred post-binding but prior to early viral protein synthesis. Additional work toward a more fundamental understanding of how viruses become inactivated is key for the development of new disinfection technologies and novel sensors to detect infectious viruses in drinking water.