Re: Detection of SARS‐CoV‐2 in vaginal swabs of women with acute
SARS‐CoV‐2 infection: a prospective study
[Author’s title: Maternal transmission of SARS-COV-2 to the neonate,
and possible routes for respiratory transmission]
Sir,
We read with great interests the article by
Anat
Schwartz and colleagues, entitled “Detection of SARS‐CoV‐2 in vaginal
swabs of women with acute SARS‐CoV‐2 infection: a prospective study”.
The prospective study contained important information, which included
the participant women in both reproductive and non-reproductive years.
In their findings, of the 35 patients sampled, 2 (5.7%) had a positive
vaginal RT‐PCR for SARS‐CoV‐2, one was pre-menopausal and the other was
a post-menopausal woman, however, they did not detect the presence of
viral colonization in the vagina in five pregnant women.
The detections of virus in the vagina and breast milk in pregnant women
have been reported in similar studies, and concluded that vaginal
delivery or breast milk feeding might be low risk, for the major sampled
vagina and breast milk had negative RT‐PCR for SARS‐CoV‐2.
As a retrospective study reported 42 pregnant women with COVID‐19, the
different infection rates of their neonates were analyzed between
vaginal birth and Caesarean delivery. Though the authors concluded that
vaginal delivery was associated with a low risk of intrapartum
SARS-Cov-2 transmission to the newborn, we would like to ask whether all
infected mothers had a mask during labor? If yes, partial or whole
course? Furthermore, whether the virus concentrations in the delivery or
labor room after vaginal birth or Caesarean delivery could be similar or
very different?
Clinically, maternal transmission of SARS‐COV‐2 to the neonate through
the respiratory routes might have been seriously underestimated.
SARS-CoV-2 spreads through contact (via larger droplets and aerosols),
and longer-range transmission via aerosols, especially in conditions
where ventilation is poor and the virus characters as strong
infectivity, rapid and wide spread. COVID-19 infected mother may release
lots of droplets containing virus in the room during labor when using
deep breathing and abdominal pressure. The delivery room satisfies the
condition of high risk of respiratory transmission. The neonate might
breathe the virus into the lung with the first crying, which might be an
important time-point for the neonate infected with virus. And it might
be the major difference between vaginal and cesarean deliveries, we
should not solely consider whether the vagina secretion and breast milk
contain virus. More in-depth and detailed studies, including randomized
studies should be performed to confirm the risks of respiratory routes
for maternal transmission of SARS‐COV‐2 to the neonate, and further
elucidation of the safety the mode of delivery is necessary to examine
these conclusions from a clinical perspective.
Rui-Hong Xue1, He-Feng Huang2,3,4,5
1Department of Obstetrics and Gynecology,
International Peace Maternity and Child
Health Hospital, School of Medicine, Shanghai Jiao Tong University,
Shanghai, China
2Center of Reproductive Medicine, International Peace
Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao
Tong University, Shanghai, China
3Institute of Embryo-Fetal Original Adult Disease
Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai
Jiao Tong University, Shanghai, China
4Shanghai Key Laboratory of Embryo Original Diseases,
Shanghai, China
5Shanghai Municipal Key Clinical Specialty, Shanghai,
China