A Long-Standing Measles Complication That Many Are Unaware Of

(SeaPRwire) –   Measles, largely eradicated in the developed world for decades, is making a comeback. In January, the U.K. lost its measles elimination status when vaccination rates fell below 95%, the threshold needed to suppress the highly contagious virus. The U.S., where outbreaks continue this year, may follow suit.

Vaccine hesitancy is driving the resurgence—but contrary to claims by anti-vaccine activists, measles is not merely a short-lived respiratory illness that resolves within days. Scientists now recognize that the virus primarily targets the immune system. Beyond triggering rare but fatal neurological complications that can emerge years after infection, measles can also dismantle the body’s immune memory by destroying infection-fighting cells.

While most people recover from measles, their immunity against everyday infections—often encountered daily—can remain impaired, according to Rik de Swart, a virologist at Erasmus University Medical Center in Rotterdam, Netherlands, who has researched this phenomenon known as immune amnesia. In some cases, full recovery of immune function may take years.

What makes measles so dangerous

Transmitted through airborne droplets, measles is extremely contagious: up to 90% of unvaccinated individuals exposed to the virus will contract it. Historically, millions of children died annually from the disease. The introduction of the first measles vaccine in 1963 led to dramatic declines in U.S. cases, and measles was declared eliminated in the country in 2000.

That same year, Japanese biologists identified a receptor—called CD150—that the measles virus uses to enter cells. Although the virus spreads through the air, this receptor wasn’t primarily located in nose or lung lining cells. Instead, it was found on immune cells. “This receptor is especially expressed on memory cells of the immune system,” explains de Swart. “That means the virus predominantly infects and destroys memory cells—the very cells that remember past pathogens and help protect against future encounters.”

Measles is deadlier than most people think

For many years, doctors and researchers observed that measles infections often triggered prolonged periods of vulnerability to other illnesses in children, though the underlying cause remained unclear. In 1995, studies revealed that vaccinating children in developing countries against measles significantly reduced overall child mortality—not just from measles itself, but from other infections as well. The vaccine appeared to be conferring broader protection.

Epidemiologists later discovered that the effects of measles infection could persist for years. In 2015, Dr. Michael Mina, de Swart, and colleagues found that children infected with measles faced a significantly elevated risk of dying from other infectious diseases for two to three years following recovery. “We were effectively saying measles was associated with as much as 50% of all childhood infectious disease deaths not officially attributed to measles,” Mina noted.

Analyzing blood samples from unvaccinated children taken before and after measles infection, the team discovered that the virus severely impaired the body’s ability to recognize common pathogens due to the loss of memory immune cells. “Ultimately, we proved that initial hypothesis immunologically, showing that measles actually erased anywhere between 20 and 75% of somebody’s immunological memory pool,” Mina said. He hypothesizes that after a measles infection, children must rebuild their immune defenses by re-exposing themselves to various infections—a process that can take several years.

Will we see a return to the pattern of serious childhood illness?

Measles frequently appeared in children’s stories and nursery rhymes, often depicting lengthy periods of sickness and recovery.

This literary portrayal likely reflects multiple historical factors. Many tales predate antibiotics—which, while ineffective against measles, were crucial in treating many other childhood infections—as well as numerous vaccines. Additionally, up until World War I, societal attitudes favored extended convalescence, which Krienke observes permeates the literature of the era. “This kind of slow, delayed recovery is across all of the literature of the time period,” she says.

Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, warns that this historical reality should serve as a warning to parents today. “If we continue along our current path, where more and more parents are choosing not to vaccinate their children, this phenomenon will become even more evident,” he wrote in an email. “Tough times ahead.”