Submitted to: Applied and Environmental Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/26/2010
Publication Date: 1/3/2011
Citation: Butkus, M.A., Hughes, K.T., Bowman, D.D., Liotta, J.L., Jenkins, M., Labare, M.P. 2011. Inactivation of Ascaris suum by short-chain fatty acids. Applied and Environmental Microbiology. 77:363-366. Interpretive Summary: The human pathogenic nematode Ascaris lumbricoides infects millions of people world-wide. The eggs of this pathogen are dispersed in the environment in feces and are highly resistant to ambient environmental conditions although extreme heat (greater than 40ºC) and ultra violate radiation will render the eggs non-viable. The closely related swine parasite Ascaris suum is used routinely as a surrogate for testing methods designed to disinfect A. lubricoides. In this study, researchers from the U.S. Military Academy, Cornell University, and ARS J. Phil Campbell, Sr., Natural Resource Conservation Center evaluated the efficacy of short chained fatty acids (FA) on inactivating Ascaris eggs in water and sewage sludge. From this study a model was developed that predicts the toxicity of FA based concentration and level of acidity (pH) on Ascaris eggs. The information in this paper will aid public health agencies, and the U.S. Military in managing the dissemination of A. lubricoides in the environment and prevent the spread of human infection.
Technical Abstract: Ascaris suum eggs were inactivated in distilled water and digested sludge by butanoic, pentanoic and hexanoic acids. The fatty acids (FA) were only effective when protonated and at sufficient concentration. The conjugate bases were not effective at the concentrations evaluated. Predictions from an inhibition model (IC50) based on quantitative structure-activity relationships were congruent with inactivation data.