The new coronavirus usually infects humans through the respiratory tract and causes damage to the respiratory system and various organs of the human body. It broke out at the end of 2019 and spread rapidly around the world, causing billions of infections and millions of deaths, which had a great negative impact on society.
Recently, many netizens have expressed on social media that they are "wearing masks", and many topics about the new crown have once again become hot searches.
Tea is one of the most popular beverages in the world, especially in China. Drinking tea is considered a healthy lifestyle because tea contains a variety of beneficial compounds such as catechins, tea polyphenols and caffeine. Many studies have shown that tea extracts have anti-inflammatory, anti-tumor, antibacterial and antiviral benefits.
Recently, researchers from the University of Georgia in the United States published a research paper titled "Screening Commercial Tea for Rapid Inactivation of Infectious SARS-CoV-2 in Saliva" in the journal "Food and Environmental Virology".
Studies have shown that at a concentration of 10 mg/mL, black tea can kill 99.9% of the new coronavirus in the mouth within 10 seconds of contact, and green tea, raspberry ginger tea, eucalyptus mint tea, and mint mixed tea can kill 96-99% of the new coronavirus. At a concentration of 40 mg/mL, contact with these five teas for 10 seconds can kill 99.9% of the new coronavirus in the mouth.
The results show that drinking these five teas or gargling with tea can prevent new coronavirus infection to a certain extent and inhibit post-infection viruses.
In this study, researchers purchased 24 types of tea from the market, soaked each tea for 15 minutes, and there were two brewing concentrations of tea: normal drinking concentration (10 mg/mL, 200 ml of water to soak 2 grams of tea leaves) and 4 times the drinking concentration (40 mg/mL, 50 ml of water to soak 2 grams of tea leaves), and analyzed the inactivation rate of different concentrations and types of tea on the new coronavirus in the mouth.
After initial screening, five types of tea were found to significantly reduce the novel coronavirus in saliva, including black tea, green tea, raspberry ginger tea, eucalyptus mint tea, and mint blended tea.
Next, the researchers analyzed the inactivation rate of the novel coronavirus in the mouth of these five teas at different concentrations, when in contact for 60 seconds and 10 seconds.
The results showed that when in contact for 60 seconds, at a concentration of 40 mg/mL, all five teas could kill 99.9% of the novel coronavirus. At a concentration of 10 mg/mL, black tea could kill 99.9% of the novel coronavirus, while green tea, raspberry ginger tea, eucalyptus mint tea, and mint blended tea were relatively lower (1.6-1.9 logarithms).
When in contact for 10 seconds, at a concentration of 40 mg/mL, all five teas could kill 99.9% of the novel coronavirus, with no difference. At a concentration of 10 mg/mL, black tea can kill 99.9% of the new coronavirus, while green tea, raspberry ginger tea, eucalyptus mint tea, and mint blended tea can kill 96-99% (1.4-2 logarithms) of the new coronavirus.
Further analysis found that tea polyphenols were significantly associated with viral reduction and may play a key role in antiviral effects.
In addition, the researchers also analyzed the inhibitory effects of tea at a concentration of 10 mg/mL at multiple stages of infection. The results showed that these five teas had a preventive effect on new coronavirus infection in susceptible cells (68-90%) and also had a preventive effect after infection (94-98%). However, these teas had the most obvious inhibitory effect when they were in direct contact with the virus during infection (99-99.9%).
Therefore, these five teas may be most effective in inhibiting viral attachment or entry into cells, and can also inhibit post-infection viruses and prevent infection to a lesser extent.
The researchers said that tea cannot replace treatment and is not recommended as an independent intervention against the virus, because the virus also replicates in the nasal cavity. When a person tests positive, the virus may have reached the lungs, but it can be used as an additional intervention to prevent new coronavirus infection.
In summary, the results show that at normal drinking concentrations, black tea can kill 99.9% of the new coronavirus in the mouth in 10 seconds, and green tea, raspberry ginger tea, eucalyptus mint tea, and mint blended tea can kill 96-99% of the new coronavirus. Drinking or gargling can prevent new coronavirus infection to a certain extent and inhibit post-infection viruses.
More clinical trials are needed to better understand the possible impact of these results on patients infected with the new coronavirus.
