Bolinger, Hannah Kathleen. The survival of enterococcus faecalis and bacteroides fragilis on four different food contact surfaces. Retrieved from https://doi.org/doi:10.7282/T3GB22H6
DescriptionChanges to the gut microflora resulting from a number of environmental influences are well documented. (123) Enteric pathogens have been shown to promote a shift away from the predominance of Gram negative toward Gram-positive species however, evidence of Noroviruses initiating such changes has only recently been documented. (90, 135) Noroviruses (NoV) are the most common cause of gastroenteritis in the world accounting for about 50% of all outbreaks of foodborne illness and more than 90% of outbreaks with a non-bacterial origin worldwide (97, 108). Generally self-limiting, nausea, vomiting, and diarrhea are common symptoms of the illness (80). Nearby surfaces may become contaminated with aerosolized fecal matter or vomitus from being ill. These contaminated surfaces may be involved in the propagation of an outbreak as well as provide a surface that investigators may swab to obtain a sample for PCR amplification, which is the preferred method of NoV detection by the CDC (15). However, concerns about false outcomes resulting from contamination or amplification of inactivated genomic material leave room for supporting diagnostic methods to be investigated. Bacterial indicators have been used in the past to indicate the presence of fecal contamination and various indicators have been investigated to predict the presence of specific pathogens. Utilizing surface contamination and the change to the gut microbiome upon NoV infection could provide a new diagnostic technique for NoV diagnosis. The first step to creating this new diagnostic would be investigating the survival of the relevant bacterial species on surfaces of interest. It was the purpose of this thesis to study the survival of E. faecalis and B. fragilis on stainless steel, ceramic, glass, and polystyrene. E. faecalis survived above the detection limit for 16 weeks on all surfaces except ceramic on which, it was able to survive only 8 weeks above the detection limit. B. fragilis was able to survive 48 hours on all surfaces tested.