Covid-infected foetuses could risk long-term brain complications: New findings

Aditi Tandon

New Delhi, June 19

Until recently, it was widely believed that SARS-CoV-2, the Covid-19 causing virus, did not cross from the mother to the developing foetus during a maternal case of the infection.

But new evidence has emerged to show neurodevelopmental deficits in neonates exposed to Covid-19 in the uterus through the infected mother.

A study published in the Science Direct, the world’s leading source for scientific, technical, and medical research, says neonates exposed to maternal Covid-19 during later development stages of the foetus have displayed neurodevelopmental and motor skill deficiencies.

Researchers have demonstrated SARS-CoV-2 transmission from mother to foetus during later stages of gestation, (second and third trimesters) possibly through the circulatory system.

“In the foetal brain, we found that SARS-CoV-2 infects blood vessels, neurons, glial cells, and cells of the choroid plexus, and leads to an increase in gliosis even after viral clearance. Altogether, our findings suggest that a prenatal case of Covid-19 may have critical implications for neurodevelopment and function in the offspring,” study authors say.

Since the study was conducted on the mouse model and was conservative, authors add, “our findings suggest that the consequences on neurodevelopment may be more severe in humans, having higher natural susceptibility to SARS-CoV-2 infection than mice.”

The researchers further showed viral infection rates and levels to be higher in males than in female foetuses. They said more studies were needed to elucidate the role of sex in infection differences, as there are several possible explanations for our observations.

“For example, estrogen has been shown to act as a protective factor against various viral pathogens including SARS-CoV-2, while androgens have been correlated with increased vulnerability,” the paper says.

On the importance of the research the authors explain that the findings of the study have vital implications for neurodevelopment.

“Infection-induced damage to the blood vessels can result in narrowing, ruptures, or leaks, which can lead to stroke or haemorrhage in the young or adult brain later in life. Glial cell dysfunction and gliosis have also been associated with a number of complications and disorders of the brain,” the authors warn.

Overall, the new findings give rise to the question of what functional effects, such as behavioural and cognitive alterations, does infection of the developing brain have later in life.