Cholera is a diarrheal disease caused by intestinal bacterium Vibrio cholerae. This enteric disease affects millions of patients each year and it is primarily caused by contaminated food or water. V. cholerae (Vc) infected patients can be asymptomatic or develop severe acute diarrheal symptoms. We previously used metagenomic sequencing to characterize the gut microbiota of household members of patients with cholera and found that gut microbe Rothia mucilaginosa (Rm) is present in higher relative abundance among patients with Vc compared to uninfected individuals. Here we aim to investigate how this gut bacteria interact with Vc and/or impact Vc biofilm formation. To analyze Vc biofilm, we co-cultured Rm with Vc at 37C for six hours and quantified biofilm formation using a microtiter dish assay with crystal violet staining. We first tested the biofilm formation of Vc and Rm in monocultures as controls and then we performed co-culture assays with different ratios including 1:1, 1:10, and 2:1 Vc to Rm. Additionally, heat killed and spent-cell supernatant conditions of Rm were also used to determine the interaction between Vc and Rm. Preliminary results from our biofilm assays suggests that Rothia mucilaginosa promotes increased biofilm formation of Vc. In conclusion, we found that native members of the gut microbiome can induce formation of biofilms and this interaction between gut microbe and pathogen has the potential to affect the disease outcomes.

Since late 2020, vaccination rates against SARS-CoV-2 have increased with 64% of the U.S. population fully vaccinated as of February 2022 [CDC, 2021]. Although vaccines are an effective method of protection, breakthrough cases have been occurring especially with variants of concern (VOC). Vaccination has remained protective against severe disease for multiple VOCs, including Delta and more recently Omicron. It is important to understand how different levels of vaccination, such as the number of doses received, impact symptom severity as additional VOCs continue to emerge. I utilized data collected from the Husky Coronavirus Testing research program, which provides testing to students, faculty, and staff at the University of Washington, to evaluate the relationship between severity of COVID-19 symptoms and number of doses received and type of vaccine received. Self-reported symptom severity data was collected from individuals who completed a follow-up questionnaire 7 days after testing positive for COVID-19. This analysis can help us to learn more about vaccination status and its impact on illness severity in those infected with the omicron variant. From this research I anticipate vaccinated individuals to report mild COVID-19 symptoms and those who are unvaccinated, or only slightly vaccinated to report more moderate or severe symptoms.