SARS-CoV-2 Survival in Common Non-Alcoholic and Alcoholic Beverages

Abstract

SARS-CoV-2, the causative agent of COVID-19, is known to be transmitted by respiratory droplets and aerosols. Since the virus is shed at high concentrations in respiratory secretions and saliva, SARS-CoV-2 would also be expected to be transmitted through activities that involve the transfer of saliva from one individual to another, such as kissing or sharing beverages. To assess the survival of infectious SARS-CoV-2 in common beverages, we quantified infectious virus by plaque assays one hour after inoculation into 18 non-alcoholic and 16 alcoholic beverages, plus saliva, and also 7 days later for 5 of these beverages. SARS-CoV-2 remains infectious with minimal reductions in several common beverages, including milk and beer. However, cocoa, coffee, tea, fruit juices, and wine contain antiviral compounds that inactivate SARS-CoV-2. Although hard liquors containing 40% alcohol immediately inactivate SARS-CoV-2, mixing with non-alcoholic beverages reduces the antiviral effects. In summary, SARS-CoV-2 can be recovered from commonly consumed beverages in a beverage type and time-dependent manner. Although aerosol or droplet transmission remains the most likely mode of transmission, our findings combined with others suggest that beverages contaminated with SARS-CoV-2 during handling, serving, or through sharing of drinks should be considered as a potential vehicle for virus transmission.

Keywords: COVID-19; SARS-CoV-2; beverages; plaque assay; transmission.

Figure 1

Survival of SARS-CoV-2 in milk and cocoa. SARS-CoV-2 was recovered from bovine- and plant-based milk products (A) and different concentrations of cocoa dissolved in water (B) immediately after inoculation (0 h) and at 1 h and 24 h after inoculation. Infectious virus was quantified by plaque assay on Vero E6 cells and shown as log PFU/mL. No significant differences were detected between inoculum and 0 h for any of the milk products except chocolate milk (p = 0.0122). 10%, 5%, and 2.5% cocoa were significantly reduced at 0 h compared with the inoculum (p < 0.0001). The inoculum is shown as a solid gray line (4.3 log PFU/mL) and the detection limit of the plaque assay is shown as a dashed line (0.7 log PFU/mL). Significant differences between 0 h and inoculum are shown with an asterisk. Significant differences between means at 0 h and later time points are shown by brackets and asterisks (* <0.05; ** <0.01; *** <0.001). Error bars = SEM.

Figure 2

Survival of SARS-CoV-2 in coffee, tea, soda, energy drink, and pediatric electrolyte beverage. SARS-CoV-2 was recovered from beverages immediately after inoculation (0 h) and 1 h later, quantified by plaque assay on Vero E6 cells and shown as log PFU/mL. Infectious virus was significantly reduced at 0 h in coffee, tea, dark soda (p < 0.0001), and energy drink (p < 0.0177). The inoculum is shown as a solid gray line (4.3 log PFU/mL) and the detection limit of the plaque assay is shown as a dashed line (0.7 log PFU/mL). Significant differences between 0 h and inoculum are shown with an asterisk. Significant differences between means at 0 h and 1 h are shown by brackets and asterisks (* <0.05; *** <0.001). Error bars = SEM.

Figure 3

Survival of SARS-CoV-2 in beer. SARS-CoV-2 was recovered from beverages immediately after inoculation (0 h) and 1 h later, quantified by plaque assay on Vero E6 cells, and shown as log PFU/mL. The inoculum is shown as a solid gray line (4.3 log PFU/mL) and the detection limit of the plaque assay is shown as a dashed line (0.7 log PFU/mL). Significant differences between means at 0 h and 1 h are shown by brackets and asterisks (* <0.05; ** <0.01). Error bars = SEM.

Figure 4

Survival of SARS-CoV-2 in hard cider, wine, and fruit juices. SARS-CoV-2 was recovered from hard cider and wine (A) and fruit juices (B) immediately after inoculation (0 h) and 1 h later. Infectious virus was quantified by plaque assay on Vero E6 cells and shown as log PFU/mL. All beverages significantly reduced infectious virus immediately after inoculation at 0 h compared to inoculum (p < 0.0001). The inoculum is shown as a solid gray line (4.3 log PFU/mL) and the detection limit of the plaque assay is shown as a dashed line (0.7 log PFU/mL). Significant differences between 0 h and inoculum are shown with an asterisk. Significant differences between means at 0 h and 1 h are shown by brackets and asterisks (* <0.05; ** <0.01; *** <0.001). Error bars = SEM.

Figure 5

Survival of SARS-CoV-2 in liquor. SARS-CoV-2 was recovered from liquors (A) and mixed beverages consisting of vodka and club soda to different alcohol percentages (B) immediately after inoculation (0 h) and 1 h later, quantified by plaque assay on Vero E6 cells and shown as log PFU/mL. Infectious virus was significantly reduced immediately after inoculation (0 h) in liquors (p < 0.0001). The inoculum is shown as a solid gray line (4.3 log PFU/mL) and the detection limit of the plaque assay is shown as a dashed line (0.7 log PFU/mL). Significant differences between 0 h and inoculum are shown with an asterisk. Significant differences between means at 0 h and 1 h are shown by brackets and asterisks (* <0.05; ** <0.01). Error bars = SEM.

Figure 6

Correlations between beverage characteristics and percent reduction in virus titer at 1 h. Higher concentrations of sugar (A) and alcohol (D) correlate with greater reduction in virus titer by 1 h post-inoculation (p = 0.0378, and 0.0189, respectively). Increased percentage of fat (B) and higher pH (E) correlate with less reduction in virus titer by 1 h post-inoculation (p = 0.0478 and <0.0001, respectively. Shaded areas = confidence intervals (0.05). No correlation was found between protein (C) or caffeine (F) content and reduction in virus titer by 1 h post-inoculation (p > 0.05). Bivariate analysis, JMP.

Figure 7

Survival of SARS-CoV-2 in saliva from vaccinated (vax saliva) and unvaccinated (Unvax saliva) individuals compared to water and media controls. SARS-CoV-2 was recovered immediately after inoculation (0 h) and at 1 h and 7 d after inoculation, quantified by plaque assay on Vero E6 cells, and shown as log PFU/mL. The inoculum is shown as a solid gray line (4.3 log PFU/mL) and the detection limit of the plaque assay is shown as a dashed line (0.7 log PFU/mL). No statistically significant differences were identified. Error bars = SEM.