Researchers tested the efficacy of five different types of tea at reducing the amounts of virus in the mouth.
For the study, the team at the University of Georgia prepared the drink using one tea bag per cup steeped for 10 minutes, with no additions such as milk or sugar.
They found that all five teas reduced the virus by at least 96 per cent within 10 seconds in the mouth, while black tea reduced the virus by 99.9 per cent.
Inactivating Covid in the mouth works as the virus often infects and replicates inside the oral cavity, passing through the middle part of the throat before reaching the lungs.
Malak Esseili, a virologist with the University of Georgia, who led the study, said: “At this stage, we are not suggesting tea as a stand-alone intervention against Covid, because the virus also replicates in the nose and may have already reached the lung by the time a person tests positive.
“But tea can be an additional layer of intervention that the patients and their families can easily adopt on a routine basis.”
She added that “having something that is accessible, easily prepared, and suitable for all the family would be ideal” to protect against the virus.
The results come after a study published last year in Japan found that drinking a matcha latte or a green tea could “effectively inactivate” Covid.
Scientists at the Kyoto Prefectural University of Medicine found that chemicals in tea could bind to the spike protein sticking out from the surface of the virus and prevent it from infecting cells.
Two molecules based in tea, called EGCG and TFDG, were found to “strongly suppress” the infectivity of the Omicron lineage of the virus in particular.
Tea is often used in the treatment of respiratory illnesses, including flu and the common cold.
