Study reports coronavirus underwent mutation within an infected newborn.
For the first time, researchers have found evidence of the novel coronavirus undergoing mutation in an infected newborn. According to the study, researchers observed the genetic change five days after birth.
Dr Mehreen Zaigham reports that a 27-year-old pregnant woman had presented to Skåne University Hospital, in Malmo, Sweden, with severe abdominal pain. Along with a history of fever, dry cough, and reduced fetal movements. Doctors immediately performed a cardiotocograph (CTG) test which showed a low fetal heart rate. Therefore, doctors rushed her for an emergency caesarean section. The woman was in her 34th week of pregnancy at the time.
Upon birth, the newborn required resuscitation and oxygen supplementation. The hospital staff then kept the newborn in isolation. During the first 60 hours of life, the newborn had no contact with the mother or any family member. As per national guidelines, hospital staff also collected nasopharyngeal swabs from the mother upon admission and 48 hours after delivery from the neonate. Both of which came back positive.
Since the baby had been isolated from the mother directly after the caesarean and had not come in contact with other family members when these tests were done, the findings confirmed that the baby was indeed infected before it was born.
Dr. Mehreen Zaigham, Postdoctoral Research Fellow, Obstetric & Gynecology, Skåne University Hospital
A Genetic Shift
The newborn in the study developed no other symptoms and tested positive for antibodies soon after. Since the mother’s breast milk lacked antibodies, researchers believe the newborn’s immune system neutralized the virus itself.
Researchers performed whole-genome sequencing to confirm the infection was acquired in-utero. Swabs from both mother and fetus along with samples of the placenta underwent genetic sequencing. Results showed that the viral genome in both mother and newborn was identical. However, genetic sequencing done on a neonatal sample collected a few days later, showed a change in the genetic sequence of the virus. The mutation occurred five days after delivery. Researchers believe a change in environment from the mother’s womb may have stimulated the genetic change.
The study also reported changes in the placenta. This included widespread damage due to inflammation on both the maternal and fetal side. Consequently, researchers believe that even a mild infection in pregnant women can lead to placental dysfunction; thus, resulting in low oxygen in the fetus. However, not all transplacental coronavirus transmissions lead to severe consequences in newborns.
The case study is published in The British Journal of Obstetrics and Gynaecology.
Reference:
Zaigham, Mehreen, et al. “Intrauterine Vertical SARS‐CoV‐2 Infection: a Case Confirming Transplacental Transmission Followed by Divergence of the Viral Genome.” BJOG: An International Journal of Obstetrics & Gynaecology, 2021, doi:10.1111/1471-0528.16682.
