Before the 1960s, millions of children contracted the measles annually. Three decades later, the disease was almost nonexistent, and child mortality rates from infectious diseases had plummeted. Now, in the late 2010s, the plague that once laid children to rest before they had even begun to live has made a resurgence. How did this happen, and what kind of impact will it have on the population?

Back from the dead

The earliest accounts of the measles as a human disease emerged sometime around 500 CE. Recognizable by its distinctive red mottled rash that covers the entire body, measles is one of the most virulent diseases in history. Once it is present in a community, it tends to stick around. Over time, people who have been exposed to it for long enough tend to develop an immunity to it. When it is first introduced to a new community, the death count is often devastating. In 1529, the measles was introduced to Cuba. The ensuing epidemic wiped out two-thirds of the population, many of whom had already survived a bout of smallpox just a few years earlier. In 1531, the virus was introduced to the mainland, wiping out half the population of Honduras and ravaging cities across Mexico, Central America, and the Inca civilization.

During the 1950s and 60s, Thomas Peebles and Franklin Enders collaborated on an injection that would protect children against the measles virus. Polio had once been the reigning childhood disease. In the years following the release of the polio vaccine, the rate of infection dropped drastically, and by the early 1960s, nearly twice as many children died from measles as from polio. In 1963, the duo of scientists introduced the first measles vaccine. Over the next few decades, the vaccine evolved into a two-stage inoculation, and in 1971, the MMR vaccine was introduced. Unlike the previous shot, the MMR vaccine protected recipients against measles, mumps, and rubella with a series of two injections. By the 1990s, thanks to an increase in global vaccination rates, the measles had fallen from its place as a major childhood disease.

Fiction as fact

In 1998, former medical practitioner Andrew Wakefield and 12 of his colleagues published a report in a scientific journal claiming that the MMR vaccine was linked to an increase in cases of autism among vaccinated groups. His publication sparked a movement of people who sought to protest the health risks attributed to vaccines. These anti-vaccination parents opted out of routine inoculations for their children under the assumption that they were protecting their little ones from harm. Immediately following Wakefield’s published claims, other scientific groups began research efforts to test his potentially field-altering findings, but all of their studies turned up results that directly contradicted the initial research. In 2010, Wakefield formally withdrew his publication and admitted to having falsified the report. His medical license was revoked, but the damage had already been done.

As a result of the movement in opposition to vaccines, recent years have seen the resurgence of diseases that were once nearly eradicated. Most prominent among those diseases has been the reemergence of measles. In 2018, 372 cases of measles were reported across 10 states. Between January 1 and February 7, 2019, 101 cases have already been reported among those same 10 states that have provided data to the CDC. The misinformation spread by Wakefield has snowballed over the years, creating what could become a substantial problem for immunocompromised individuals. When 95% of a community is vaccinated, diseases have a hard time spreading from person to person because there are so many immune individuals between the infected and susceptible individuals. As the percentage of vaccinated individuals decreases, more pathways for infection open up, allowing diseases to spread more readily. The principle of maintaining a 95% vaccination rate to protect those who can’t receive inoculations is the basis of herd immunity.

Lasting repercussions

Among communities where the anti-vax movement is widespread, vaccination rates are significantly lower, making them the perfect petri dish for resurfacing diseases to take hold. Beginning in late 2018, Portland, Oregon experienced a large measles outbreak that has affected some 54 children as of February 6, 2019. The epidemic was fueled by vaccination rates well below the 95% required to maintain herd immunity. While measles has been the topic of most news reports, outbreaks of other vaccine-preventable diseases such as whooping cough have also been steadily rising. Individuals opting out of childhood vaccinations are not only putting their children at risk for potentially deadly diseases. Children who are too young to receive the injections or whose immune systems are weakened are also in danger of contracting these diseases. In a community with a 95% vaccination rate, herd immunity would protect these individuals, but with numbers hovering around 70 and 80%, herd immunity no longer provides that lifesaving buffer.

The fight might not be over for a child, even if they survive the initial measles infection, which can result in 104-degree fevers and complications such as pneumonia, seizures, and meningitis. Multiple studies have shown that the measles virus has the potential to reset the body’s immune system, leaving affected children in a weakened state for up to three years after the initial infection. The studies were prompted by the notable drop in childhood death by other infectious diseases following the introduction of the measles vaccine. Measles has now been proven to retroactively erase immune memory, leaving children who recover from the measles in an immunocompromised state for years after the virus has left the body. Their depleted immune system has a harder time fighting off other infections, which could lead to death from a different disease down the road that their systems could have otherwise handled. The long-term effects of recent measles outbreaks are unknown, but there is a possibility that we will see a spike in child mortality rates in future years.