Alliance for Pandemic Preparedness

June 17, 2020

Evaluation of SARS-CoV-2 in Breastmilk from 18 Infected Women



  • [pre-print, not peer reviewed] One out of 64 (2%serial breastmilk samples from 18 SARS-CoV-2 infected women (1 asymptomatic) in the US was positive for SARS-CoV-2 by RT-PCR. The positive sample was collected on the day of symptom onset. Samples 2 days prior and 12 and 14 days later were negative and viral culture of the positive sample was negative. In a separate analysis, replication-competent virus was added to breastmilk from uninfected women. After Holder pasteurization, a process commonly performed by donor milk banks, these samples were all RT-PCR negative. These results provide some evidence that transmission of SARS-CoV-2 via breastmilk is unlikely either directly from a nursing mother or via donor milk that has been pasteurized 

Chambers et al. (June 16, 2020). Evaluation of SARS-CoV-2 in Breastmilk from 18 Infected Women. Pre-print downloaded June 17 from