Melbourne, Australia: Scientists in Australia have identified an immune system overreaction as a key driver of life-threatening influenza complications during pregnancy, offering a potential new target for treatment ahead of the winter flu season.
While influenza typically remains confined to the upper airways in most people, the study shows that in pregnancy, the heightened immune response can disrupt vascular function, increasing risks for both mother and fetus, said a statement from Australia's Royal Melbourne Institute of Technology (RMIT).
Researchers identified a viral sensor in the immune system, known as TLR7, that can become overactive during pregnancy, amplifying inflammation and spreading disease beyond the respiratory tract into the bloodstream, it said.
Blocking TLR7 could help protect developing babies by stopping the placenta from becoming overly inflamed during flu infection, said the study published in Science Advances.
"The findings shift understanding of how respiratory viruses affect pregnancy, showing that harm is not caused by the virus directly reaching the fetus, but by an overactive maternal immune response that disrupts vascular function," said study lead author Stella Liong from RMIT's School of Health and Biomedical Sciences.
The study also reinforces the importance of vaccination, which experts say remains the most effective protection against severe influenza during pregnancy.
