A measles outbreak in 19 states has infected nearly 500 people, including eight in California. While many think that getting infected with the virus confers benefits on the immune system, doctors say this is not true. Instead, measles destroys the memory cells that provide resistance against other bugs and viruses.
Even a mild case of measles can cause “immune amnesia,” where patients lose their ability to fight off recurring illnesses they previously had no problem with. This means that people infected with measles are more susceptible to serious or fatal complications from other diseases.
Measles virus travels through airborne droplets, infecting the lymph nodes and bloodstream, which then destroy critical immune cells such as memory B and T cells. These cells are crucial for fighting off infections in the future.
In contrast, vaccines stimulate the production of these memory cells without destroying them, providing immunity without the negative consequences. The measles, mumps, and rubella vaccine’s approval in 1963 marked a significant turning point in understanding the virus’s impact on the immune system.
Studies have shown that childhood deaths from other infectious diseases remained significantly higher for two to three years after measles outbreaks. Once vaccines were introduced, these cases fell by about half. In some studies, it was found that the virus wiped out up to 73% of unvaccinated children’s pre-existing antibodies to various pathogens.
Experts emphasize that getting vaccinated is crucial in preventing both measles and the loss of immune protections. As of late March, 97% of people sickened in the current outbreak were either unvaccinated or didn’t disclose their vaccine status.
Source: https://www.latimes.com/science/story/2025-04-03/how-even-mild-measles-infections-can-lead-to-serious-illness-later