Sanitation of virus in human excreta and animal manure: a focus on mechanisms underlying inactivation heterogeneity

Water, sanitation and hygiene interventions are among the most significant health interventions addressing the worldwide burden of diarrheal disease and environmental enteropathy. It was recently established that despite an increase in global toilet coverage, the proportion of safely managed fecal waste remains low. Therefore, on-site storage and treatment still represent the best opportunities to reduce pathogen load. Viruses are particularly persistent pathogens. However, adequate storage or digestion of fecal waste can strongly reduce the number of viruses by creating adverse conditions to their survival. Although temperature, pH and ammonia (NH3) are commonly reported as primary virus inactivation factors, the mechanisms underlying virus reduction remain unclear. This work aims to shed light on the virus inactivation mechanisms in human excreta.