The effect of whey protein on viral infection and replication of SARS-CoV-2 and pangolin coronavirus in vitro

Abstract

Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA has been detected in human breastmilk, infants’ safety with breastmilk feeding is of great concern for women with coronavirus disease 2019 (COVID-19). 1 It is known that milk has antiviral properties. 2 However, little is known about the antiviral property of human breastmilk to SARS-CoV-2 and its related pangolin coronavirus (GX_P2V). Here we present for the first time that whey protein from human breastmilk effectively inhibited both SARS-CoV-2 and GX_P2V by blocking viral attachment and viral replication at entry and even post entry. Moreover, human whey protein inhibited infectious virus production, as proved by the plaque assay. We found that whey protein from different species, such as cow and goat, also showed anti-coronavirus properties. Commercial bovine formula milk also showed similar anti-SARS-CoV-2 activity.