Post Reply - measles 2025

What’s happening in your blood during measles?

The mechanism for increased death after measles is driven by two main things: a suppressed and dysfunctional immune response and the development of immune amnesia. These two outcomes are driven by multiple events that impact certain cell numbers, types and functions.

Initially, there is a measurable but temporary drop in total lymphocyte numbers (lymphopaenia). Some of the disappearance of these cells from the blood is likely due to them moving into different body compartments – the lymph nodes in particular. Initial lymphopaenia depresses total lymphocyte numbers, then MeV-specific lymphocytes surge back and clear the virus. However, the composition of the rest of the newly made and released lymphocytes is changed.

There is also a major impact related to which cells MeV infects, manipulates and destroys. You may have guessed already. MeV targets and kills the T and B cells that excel at rapidly responding to the return of many viral and bacterial nemeses from days gone by.

The loss of specific lymphocyte subsets that hold our immune memories can last two to three years, and it drives the observable increase in human deaths over this longer period, well after recovery from measles.