Recent studies have revealed shocking truths about how measles harms the immune system. It calls attention to a disturbing phenomenon, immune amnesia. This condition leads to diminished immune system function. Its immune apparatus becomes less able to fight off infection. With the ongoing outbreaks of measles here in Canada and in the United States, this issue has become a hotbed of controversy. To illustrate just how serious this concern is, Stephen J. Elledge, a professor of genetics and medicine at Harvard Medical School, stresses that… He uncovers the disturbing truth that almost everyone who gets measles suffers some level of immune amnesia.
This phenomenon, known as immune amnesia, happens when the measles virus infects and wipes out cells that store immunity to previous infections. The resulting destruction erases the immune system’s “memory.” As a result, people are less able to build up immunity to diseases they’ve been vaccinated against or exposed to in the past. Babies, especially, are at increased risk because of their very young age and non-vaccination.
Indeed, the measles virus is one of the most contagious viruses we have on Earth. It’s not just its R number, which ranges from 12–18. That’s how one infected person can cause infection in up to 12 to 18 other people. That original strain of COVID-19 was closer to an R of two to three. Compared to very transmissible variants like Omicron, which most notably had R numbers near 10.
Elledge emphasizes the long recovery time for individuals who experience immune amnesia. It isn’t until two to three years later that the immune system completely rebuilds its protective memory from before the measles infection. This recovery period is a key time for rebuilding immunity. Across this timeframe, people become vulnerable to secondary infections. Their immune systems are just beginning to understand how to fight off infections properly again.
The effects of immune amnesia are most extreme in very young children. Immune amnesia literally wipes your immune system clean, which could leave you more vulnerable than ever.” Elledge said. “With respect to the measles virus, it can infect the cells that process the memories of prior immune or viral infections and other pathogens. This can infect those cells and kill them, so it physically erases the physical memory.” This process can catapult the immune system into a near-blank slate comparable to that of infants.
The vulnerability of unvaccinated children, as we saw in the year-long national measles outbreaks, is a major cause for public health alarm. When given as the MMR (measles, mumps, rubella) vaccine, it stops the spread of measles. Furthermore, it protects the immune system from the destruction caused by the virus. Estimates place the MMR effectiveness at an impressive 85 to 95 percent. This degree of protection is achieved after a single dose, usually administered at 12 or 15 months of age.
Elledge points out that although immune amnesia is prevalent in anyone who has caught measles, its severity differs from person to person. It’s an incredibly ubiquitous one. When we do, he continues, we “elevate the possible.” Since we first observed it in the majority of the children infected in our study. He stresses this is not a case where everybody is losing the same amount of immune memory. Factors such as the age and general health of the person can have a huge impact on this variation.
These results underscore vaccination’s crucial role. It provides robust protection not just against measles but against the terrible, sometimes lifelong impact measles can inflict on the immune system. During this pandemic, public health officials local, state and federal are loudly encouraging effective and robust vaccination campaigns. Their mission is to increase immunization levels for children and throughout the community.
