Systematic Review and Meta-Analysis of the Persistence and Disinfection of Human Coronaviruses and Their Viral Surrogates in Water and Wastewater

Abstract

A systematic review and meta-analysis was conducted to identify decay rate constants (k) of human coronaviruses and their viral surrogates (i.e., animal coronaviruses and the enveloped bacteriophage Phi6) in water and wastewater and disinfection rates with exposure to free chlorine and germicidal ultraviolet light (UV254). Here, 73 k were identified, with only 12 for human coronaviruses, as opposed to animal coronaviruses or Phi6. In the absence of disinfectants, k increased with temperature. Between 22 and 25 °C, mean k for coronaviruses ranged from 0.19 ± 0.06 d-1 in laboratory buffer (n = 4) to 2.9 ± 0.03 d-1 in sterilized wastewater (n = 3), which are within the ranges observed for Phi6 and nonenveloped viruses. No free chlorine or UV254 disinfection studies for coronaviruses were identified that met the systematic review inclusion criteria, although evidence from the literature suggests that coronaviruses would be inactivated if disinfectant doses recommended for nonenveloped viruses were applied. Three disinfection experiments were identified for Phi6. However, given different genome compositions and virion structures between coronaviruses and Phi6, it is not clear whether Phi6 should be used as a surrogate for evaluating free chlorine or UV254 k. Therefore, there is a critical need for additional studies that specifically evaluate disinfection kinetics of coronaviruses in the aqueous environment.