Is the transplacental transmission of COVID19 infection possible?
The case study provides information about the transplacental transmission of COVID19. The cause of COVID19 disease is SARS-CoV-2 infection which is transmitted through droplets. The only route of transmission of this infection known is its transmission through droplets rest routes are still hypothesized.
The transplacental transmission of COVID19 infection
Source
University of Bristol
Highlights
- The first pandemic of the century is SARS-CoV-2 which is transmitted through droplets.
- Other transmission methods are currently hypothesized and researchers are currently working to find out that is this infection is transmitted to the fetus.
The case study provides information about the transplacental transmission of COVID19. The cause of COVID19 disease is SARS-CoV-2 infection which is transmitted through droplets. The only route of transmission of this infection known is its transmission through droplets rest routes are still hypothesized. Some perinatal transmission methods are described by the researchers but the mode of transmission is unknown whether the mode of transmission is due to environmental exposure or transplacental or transcervical. Researchers say it is important to clarify the mode of transmission of the infection to the fetus and the suggestion is to prevent neonatal infection there is a need to optimize pregnancy and to better understand the biology of SARS-CoV-2.
Case Study
The research is performed on 23 years old lady who got admitted to the university’s hospital. The lady was at 35+2 weeks of gestation and with fever (38.6 °C) also severe cough and expectoration from 2 days before being hospitalized. After Real-time PCR both E and S gene of SARS-CoV-2 were detected in the blood sample and also in the nasopharynx and the vaginal swabs. Uneventful pregnancy was reported and the rest of the routine tests and the ultrasound examinations were normal until the COVID19 diagnosis.
After 3 days of being admitted the category III the heart rate of the fetal was traced and observed. After that category 2 cesarean section was performed using an intact amniotic membrane. Before rupture, the amniotic membrane, clear amniotic fluid was collected and it was tested positive for both the E and S genes of the SARS-CoV-2. Delayed cord clamping wasn’t performed because its effects on the SARS-CoV-2 transmissions were unknown. The women went under observations and after 6 days of delivery, she was discharged in good health conditions.
The male neonate was delivered with gestation age of 35+5 weeks and weight 2540gm.
The baby was in a negative pressure room and was in full isolation in the first day of life.
Results and Discussions
A proven case of transmission of the COVID19 infection from pregnant mother to the offspring in her late pregnancy was reported.
Some other cases of perinatal transmission are also described recently but there are a lot of unaddressed issues. In some cases they failed to detect the SARS-CoV-2 in infants or few specific antibodies are detected or in few the virus was found in few samples but the route of transmission was completely unknown. The amniotic fluid and the newborn’s blood were not tested systematically in every mother-infant pair.
Keeping into consideration a classification of pregnancy mother and the offspring definition for cases of COVID19, a congenital infection in the offspring is considered and proven that If the virus is detected in the amniotic fluid then the case qualifies the transmission of the infection through the placenta.
According to the European Centre for Disease Control recommendations, “ “E” and “S” gene of SARS-CoV-2 were found in each specimen”. It was reported that the load of the virus was much in the placental cells in comparison to the maternal blood and amniotic fluid.
The RT-PCR curves of the offspring's nasopharyngeal swabs at the 3rd and 18th day of life were higher than of 1st day of life. (the baby was in negative pressure room and was in full isolation in the first day of life)
Suggestions from findings
- Immunohistochemistry demonstrated that maternal viremia took place and the virus reached placenta.
- The histological and immunohistochemistry examinations demonstrated that the viral load is very high which signifies the inflammatory reactions are being caused significantly.
- Following placental infections are caused by the neonatal viremia.
Researchers said that their findings are consistent with a case study that describes the presence of the virus in the placental tissues and neither placental inflammation nor fetal infection was reported.
Conclusion
The researchers demonstrated that the transmission of the SARS-CoV-2 through the placenta is possible during the last weeks of pregnancy. Placental inflammation or neonatal viremia can occur due to placental transmission. Due to cerebral vasculitis neurological symptoms can be seen.
Journal References