Main findings
The study has demonstrated that, firstly, all 59 human breast milk
tested negative for rRT-PCR SARS-CoV-2; secondly, antibody levels
against SARS-CoV-2 present in the colostrum and mature milk do not seem
to vary significantly in relation to the time when infection has
occurred during pregnancy; thirdly, IgA is the predominant
immunoglobulin found in human breast milk and its concentrations are
significantly lower in the mature milk compared to the colostrum; and
fourthly, women with SARS-CoV-2 pneumonia have higher levels of both IgG
and IgA in the colostrum than those who are asymptomatic or with mild
symptoms.