Mothers who experience active genital herpes infections during early pregnancy may be more likely to have offspring that will later be diagnosed with autism spectrum disorders (ASDs).
This is according to researchers at Columbia University’s Mailman School of Public Health and the Norwegian Institute of Public Health (NIPH) who revealed what may be the first immunological evidence
that infections a mother experiences during pregnancy could affect autism outcomes in her unborn child. In the case of herpes infections, specifically the simplex virus-2 (HSV-2), “We believe the mother’s immune response to HSV-2 could be disrupting fetal central nervous system development,” said lead author Milada Mahic, PhD, a postdoctoral research scientist at the Mailman School in collaboration with NIPH.
Maternal infections have long
been associated with abnormal fetal development, although the issue has become increasingly prevalent in the public eye as a result of Zika virus
, which can lead to fetal microcephaly (unusually small head size), other brain abnormalities, and cardiovascular complications.
“Because the cause (or causes) of most cases of ASD is unknown…both genetic and environmental factors may be implicated,” Dr. Mahic explained. She added that these factors might include “gestational infection and immune activation.”
To determine whether or not high levels of herpes antibodies play a role in subsequent ASD diagnoses and whether fetal infection might be a factor, the group evaluated a cohort of 442 mothers of children with ASD and 464 mothers of children without ASD (the control group). Dr. Mahic noted that in other types of infections, such as Toxoplasma gondii
, offspring of mothers who are infected can experience latent effects even if the infection occurred before conception.
“HSV-1, HSV-2, and cytomegalovirus frequently cause persistent or latent infections,” she said, adding that the team did not believe that direct HSV-2 infections of the fetus were to blame for the ASD diagnosis since these infections are often fatal prior to birth.