Clinical implications
This study supports the idea that SARS-CoV-2 is not detected in breast milk even when active infection is present at the time of delivery and therefore, possibility of vertical transmission while breastfeeding is extremely low. Furthermore, since antibodies are found in the colostrum irrespectively of the time of infection, all women should be encouraged to breast feed their infants, undertaking strict contact precautions when there is active disease. Nevertheless, since IgA drops significantly from the colostrum to mature milk, we could speculate that they might lower even further afterwards, so public health measures should still be maintained.