Screening Commercial Tea for Rapid Inactivation of Infectious SARS-CoV-2 in Saliva.

SARS-CoV-2 infects the oral mucosa and is shed in salivary fluids. Traditionally, tea has been used by various cultures to treat respiratory ailments. The objective of this study was to identify commercially available teas that can rapidly inactivate infectious SARS-CoV-2 in saliva. Initially, tea (n = 24) was prepared as 40 mg/mL infusions and incubated with SARS-CoV-2 resuspended in water, for 5 min at 37 °C. Then, five teas that showed >3 log reduction in virus infectivity were further investigated at 40 and 10 mg/mL infusions for 60 and 10 s contact time with SARS-CoV-2 resuspended in saliva. Tea polyphenols were measured using the Folin-Ciocalteu assay. SARS-CoV-2 infectivity was quantified on Vero-E6 cell line using TCID50 assay. At 10 mg/mL infusion, black tea showed the highest reduction (3 log, i.e., 99.9%) of infectious SARS-CoV-2 within 10 s. Green, mint medley, eucalyptus-mint, and raspberry zinger teas showed similar inactivation of SARS-CoV-2 (1.5-2 log, i.e., 96-99% reduction). At 40 mg/mL infusions, all five teas showed >3 log reduction in virus infectivity within 10 s. Tea polyphenol but not pH was significantly correlated to virus reduction. Time-of-addition assay revealed that the five teas displayed preventive effects (0.5-1 log, i.e., 68-90% reduction) against SARS-CoV-2 infection of Vero-E6 cells as well as during post-virus infection (1.2-1.9 log, i.e., 94-98%). However, the highest inhibitory effect was observed when the teas were added at the time of virus infection (2-3 log, i.e., 99-99.9%). Our results provide insights into a rapid at-home intervention (tea drinking or gargling) to reduce infectious SARS-CoV-2 load in the oral cavity which might also mitigate infection of the oral mucosa.

The Effect of Water Hardness and pH on the Efficacy of Peracetic Acid and Sodium Hypochlorite against SARS-CoV-2 on Food-Contact Surfaces.

Sodium hypochlorite (NaOCl) and peracetic acid (PAA) are commonly used disinfectants with a maximum recommended concentration of 200 ppm for food-contact surfaces. The objectives of this study were to assess the effect of pH and water hardness on NaOCl and PAA efficacy against SARS-CoV-2 on stainless steel (SS). The two disinfectants were prepared at 200 ppm in water of hardness 150 or 300 ppm with the final pH adjusted to 5, 6, 7, or 8. Disinfectants were applied to virus-contaminated SS for one minute at room temperature following the ASTM E2197 standard assay. SARS-CoV-2 infectivity was quantified using TCID50 assay on Vero-E6 cells. In general, increasingly hard water decreased the efficacy of NaOCl while increasing the efficacy of PAA. Hard water at 300 ppm significantly increased virus log reduction with PAA at pH 8 by ~1.5 log. The maximum virus log reductions were observed at pH 5 for both NaOCl (~1.2 log) and PAA (~2 log) at 150 and 300 ppm hard water, respectively. In conclusion, PAA performed significantly better than NaOCl with harder water. However, both disinfectants at 200 ppm and one minute were not effective (≤3 log) against SARS-CoV-2 on contaminated food-contact surfaces, which may facilitate the role of these surfaces in virus transmission.

Maternal Bean Consumption during Pregnancy: Distribution and Nutritional Outcomes.

(1) Background: Due to their high nutritional value, we aimed to characterize the frequency and amount of maternal consumption of beans during pregnancy and their associations with diet quality and nutrient intake. (2) Methods: We conducted a secondary data analysis of US pregnant women (n = 1444) from the Infant Feeding Practices Study II, a longitudinal study that followed mother-infant pairs from late pregnancy to 1 year postpartum. Maternal bean intake (food types [dried beans, chili, and bean soup], frequency, serving size, and amount), diet quality (Healthy Eating Index [HEI]), and nutrient intake were estimated with a Food Frequency Questionnaire taken in the third trimester of pregnancy. Associations of bean consumption with diet quality and nutrient intake were examined with analysis of variance, Fisher's least significant difference tests, correlation coefficients, and coefficients of determination. (3) Results: In general, maternal bean consumption was low during pregnancy: 0.31 cups/week of dried beans, 0.37 cups/week of chili, and 0.10 cups/week of bean soup. Maternal bean consumption varied by socio-demographics and geographic regions. In comparison with those who never consumed dried beans, mothers who ate dried beans ≥ 1 time per week had a higher mean HEI score (67.5 vs. 63.6), intake of total fiber (24.4 vs. 17.4 g/day), and protein (93.4 vs. 79.9 g/day), but a lower percentage of energy from added sugar (12.6 vs. 15.2%). Higher dried bean consumption had weak-to-moderate correlations with intake of total fiber (correlation coefficient, 0.320), insoluble fiber (0.316), soluble fiber (0.310), and folate (0.286). Similar but less extensive correlations were observed for chili and bean soup consumption. (4) Conclusions: In this US cohort of pregnant women, bean consumption was low. Increased intake of beans (≥1 time per week) may improve maternal diet quality during pregnancy.