A child has died from measles complications years after being infected, California health officials said on Sept. 11.

The Los Angeles County Department of Public Health released a statement encouraging residents to ensure they are vaccinated against the highly contagious disease, saying the "school-aged" child died from a rare but fatal complication called subacute sclerosing panencephalitis (SSPE) that causes brain swelling.

The child was initially infected as an infant before they were eligible to receive the MMR vaccine for measles, mumps, and rubella, said the release. The vaccine is usually given in two doses, at 12 to 15 months and at four to six years of age.

The child was able to recover from the initial infection but developed SSPE as a result, which can occur two to ten years after infection and recovery. SSPE manifests as degenerative neurological symptoms and has no cure or effective treatment, said the LA health department. While only 1 in 10,000 people develop the complication, research has shown that the risk may be much higher, about 1 in 600, for those who get measles as infants.

“This case is a painful reminder of how dangerous measles can be, especially for our most vulnerable community members,” Los Angeles County Health Officer Dr. Muntu Davis said in a statement. “Infants too young to be vaccinated rely on all of us to help protect them through community immunity. Vaccination is not just about protecting yourself—it's about protecting your family, your neighbors, and especially children who are too young to be vaccinated.”

The United States saw the highest rate of measles cases in decades this year after an outbreak centered in Texas spread across 40 states, resulting in 1,356 confirmed cases, 171 hospitalizations and three deaths, according to the CDC as of Aug. 5, when it was declared over. The majority of those cases, 92%, were in people who were unvaccinated or had unknown vaccine status.

What is measles and how do you get it?

Measles is a highly contagious, vaccine-preventable disease caused by a virus that primarily and most severely afflicts children. According to the World Health Organization, it infects the respiratory tract before spreading throughout the body.

The virus is one of the most contagious infectious diseases; so contagious, in fact, that 90% of unvaccinated people who are exposed end up contracting it. Additionally, 1 in 5 of those people end up hospitalized, according to the CDC.

Measles spreads easily through the air when an infected person breathes, talks, coughs, or sneezes and can stay on surfaces for many hours after contact.

The MMR vaccine protects against measles with a 97% efficacy rate and is typically given to children as part of the regular vaccine course at ages 12 to 15 months for the first dose and ages 4 to 6 for the second. Some adults born in the 1960s might have received a less effective, early version of the vaccine, leading them to seek a booster shot from their doctor.

What is SSPE?

Subacute sclerosing panencephalitis, or SSPE, is a rare but fatal complication resulting from measles. It refers to a gradual inflammation of the brain that can develop two to 10 years, but mostly commonly six to eight years, after measles infection, according to Encephalitis International.

SSPE is progressive and incurable. It is seen most commonly in developing countries with lower rates of vaccine coverage and, in turn, higher rates of measles infection.

After initial infection, the virus lies dormant in the brain and, eventually, can lead to the destruction of infected brain cells. Symptoms are often "subtle" in the beginning, according to Encephalitis International, like personality changes, difficulty performing at work or school and changes in speech pattern.

Seizures or other involuntary movements ensue, progressively getting worse as the person loses more control over their body. Vision may be impacted and the sufferer will demonstrate symptoms of dementia before, ultimately, losing the ability to perform basic functions like eating, swallowing and breathing. Death is usually caused by pneumonia, according to Encephalitis International. These stages can occur over months or even years, though contracting measles in early infancy can result in a more rapidly evolving disease.

SSPE is usually diagnosed by blood and spinal fluid testing and, sometimes, an electroencephalogram (EEG).

This article originally appeared on USA TODAY: Child dies from incurable complication years after contracting measles

Reporting by Mary Walrath-Holdridge, USA TODAY / USA TODAY

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