Mechanism of Materno-Fetal Transmission
Possible discussion on the vertical transmission have been discussed by
many authors with most of them believing there’s insufficient data on
vertical transmission from the mother to her fetus24-27. Scientists have run SARS-CoV-2 RT-PCR
analysis on COVID-19 positive mothers’ breastmilk samples and specimens
of amniotic fluid, blood from the umbilical cord and throat swabs from
the neonates. All of these tests have found a negative presence of the
viral antigen in the abovementioned specimens, thereby making the
physicians unsure of materno-fetal transmission16.
A possible vertical transmission was reported in a 34 weeks gestational
mother who presented with respiratory difficulties, had
patchy-ground-glass opacities on Chest CT and had a positive RT-PCR on
nasopharyngeal swabs. Her infant girl was delivered by caesarian section
in a negative pressure isolation room and had no symptoms, but was
immediately quarantined in the neonatal intensive care unit. After 2
hours of birth, her the SARS-CoV-2 IgG level were reported to be 140.32
IU/mL and the IgM level were recorded at 45.83 IU/mL. Immunological
cytokines such as IL-6 and IL-10 were raised at 28.26 pg/mL and 153.60
pg/mL respectively with an elevated white blood cell count of
18.08 × 10^9/L. Her SARS-CoV-2 IgM and IgG level remained above
normal limits at the time of discharge 15 days after birth. This too was
consistent with abovementioned findings of negative SARS-CoV-2
breastmilk RT-PCR28.
Among other plausible ways of SARS-CoV-2 infection, in addition to
vertical transmission are: close contact transmission, droplet
transmission from family members & family visitors and nosocomial
infections. If the mother does get tested positive, the newborn should
be isolated and observed as soon as possible, and nucleic acid tests
should be carried out, too. In addition, breastfeeding should not be
performed if the mother was infected by SARS-CoV-229, even
though WHO strictly doesn’t prohibit breastfeeding, it does recommend
caution.