If a fully immunodeficient person catches a cold, what will happen?


There will be no body reaction like fever, aches, … So what will the person feel?

And in the end, will they die? What exactly will kill them?

In: 4

Very difficult to say for a “fully” immunodeficient/immunocompromised person, but broadly for a”typical” immunocompromised person the symptoms *may* be anything from severe to even absent. For example in COVID patients the range of symptoms has been extremely wide which is one of the reasons why finding suitable treatments was very difficult at the beginning of the pandemic.

Tthe progression of the disease would be very rapid and overwhelm the body’s response leaving the person open to other diseases leading to a host of other effects such as respiratory problems, Sepsis, organ failure etc.

[This article](https://www.stjude.org/treatment/patient-resources/caregiver-resources/infection-tips/infections-immunocompromised-patients.html) might help at an ELI5 level. I also found [this](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775097/) and [this](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7859698/) after a quick search for flu and immunocomrpomised patients.

I’m a nurse not an immunologist who could give you exact answers, but, it is likely the patient would be in severe respirator distress and likely unconcious.A high fever would most likely be present and in turn this would upset many of the intricate biological processes in the body.. Sepsis would probably be present in the final stages and this would lead to a horrible end.

There’s really no such thing as no immune system, because the system is so complex and involving many, many parts of the body.
During chemo, my daughter got a cold and ear infection. Now, she has about 8000 white blood cells, and about 5000 neutrophils (neutrophils are the first line WBC). During chemo, she had about 100 WBC and 0 Neutrophils.
She got a fever, ear ache, cough, etc. The parts of the immune system that cause fever aren’t dependent on blood counts. The part that creates more mucus and a cough reflex aren’t dependent on blood counts. Through antibiotics, she fought the infection and recovered in about 2 weeks without ever having a significant amount of white blood cells.