Immune research helps us understand why some kids are more prone to childhood illness

Anyone who reads my page knows I’m obsessed with the immune system. Very often its competency is a matter of life and death.

So I hail the latest research from a group of scientists as a crucial addition to our knowledge.

Severe febrile illnesses can be life-threatening to children. This is because they can stop the immune system from functioning properly, so the body is less effective at clearing infections and can send the immune system into overdrive (sepsis), causing damage to our major organs.

The researchers had noted during the Covid-19 pandemic there was an increase in the number of children being admitted to hospitals worldwide with what looked like a severe bacterial infection, with high fever, red eyes, rashes and very low blood pressure.

In reality, the children had MIS-C, a condition that can develop about four weeks after Covid-19 infection due to immune malfunction.

The present study sheds light on how children’s immune systems respond to a fever and could lead to better treatments for a range of illnesses. The work was led by a consortium of researchers at Imperial College London, King’s College London and the University of Edinburgh.

“For decades we have been working to unpick the granular detail of febrile illnesses, so we can improve treatments and reduce the impact these conditions have on children,” says Professor Michael Levin of Imperial College, who led the work alongside Edinburgh University’s Professor Manu Shankar-Hari.

“As clinicians, we may often see a child in the hospital or clinic with a fever and no other real defining symptoms, making an accurate diagnosis and targeted treatment difficult,” he adds.

The aim of their project, therefore, is to provide a clearer picture of how the immune system works in febrile illnesses and help doctors diagnose children earlier and get them the treatment they need sooner.

So they looked at different immune cells in blood samples taken from 128 children with different febrile illnesses: MIS-C (multi-system inflammatory syndrome of childhood associated with Covid-19 infection); severe bacterial infections; severe viral infections; and Kawasaki disease (a rare, severe inflammatory disease in children).

What they found was impairment of immune cells, particularly T cells, in children with MIS-C and severe bacterial infection, plus decreases in inflammatory markers called interferons – proteins that help to clear viruses from the body.

“In the clinic currently, our treatments for dysfunctional immunity tend to be poor and not targeted to individual children,” believes Dr Michael Carter of King’s College London.

The aim is to develop a simple blood test to diagnose rapidly the cause of a childhood febrile illness.