A child in California who suffered measles years ago has died from a rare complication of the disease. 

Health authorities in Los Angeles County reported on Thursday that a school-aged child had contracted measles as an infant before being old enough for the measles, mumps, and rubella (MMR) vaccine, typically administered between 12 and 15 months and again between ages four and six.

Although the child recovered from the measles infection—specifics on the timeline were not disclosed—they subsequently developed subacute sclerosing panencephalitis (SSPE), a rare brain condition occurring in about one in 10,000 unvaccinated individuals who get measles and one in 600 who acquire the virus as infants.

SSPE appears several years post initial measles infection, leading to progressive neurological damage. Symptoms include mental decline, seizures, personality changes, involuntary muscle movements, and eventually a state where the person is conscious but unable to respond.

There is no cure, and the disease kills 95 percent of patients.

No further details, like age or sex, were released about the child.  

Dr. Muntu Davis, Health Officer for Los Angeles County, emphasized in a statement that this case serves as ‘a painful reminder of the serious risks of measles, particularly for our most vulnerable community members.’

He stated, ‘Infants not yet old enough for vaccination depend on the community for protection through collective immunity. Getting vaccinated safeguards not just yourself, but also your loved ones, your neighbors, and particularly young children who can’t yet receive the vaccine.’

An unnamed school-aged child succumbed to a rare measles complication years after overcoming the initial infection during infancy (illustrative image).

The first dose of the MMR vaccine is recommended between 12 and 15 months of age, while the second comes between ages four and six. 

The two-dose shot is 97 percent effective in preventing measles. 

CDC data shows 96 percent of kindergarteners in California have received both doses of the MMR vaccine, just over the 95 percent needed to achieve herd immunity. 

However, vaccination rates nationwide are dropping. In the US overall, just 92.5 percent of kindergarteners in the 2024-2025 school year were fully vaccinated for measles, mumps and rubella.  

The child’s death comes as the US faces a near-record measles outbreak, with 1,454 cases confirmed across 42 states so far in 2025.

The majority (803) cases have been in Texas, while California has reported 20. 

Three people, including one in Colorado and two children in Texas, have died this year from the virus. 

It’s the largest outbreak since 2,126 cases were reported in 1992, according to CDC data. 

Measles is an infectious, preventable disease caused by a virus that leads to flu-like symptoms, a rash that starts on the face and spreads downward across the body, and, in severe cases, pneumonia, seizures, brain inflammation, permanent brain damage, and death.

The virus is spread through direct contact with infectious droplets or through the air. 

Patients with a measles infection are contagious from four days before the rash through four days after the rash appears.

The US has reported more than 1,400 measles cases in 2025, the highest tally since the disease was declared ‘eliminated’ in 2000

The above CDC map shows MMR vaccination rates among kindergarteners in each state

People who are not vaccinated have a 90 percent chance of getting sick if they are exposed, even from sharing the same air, briefly or hours later, with someone who has measles. Three in 1,000 people who contract measles will die.

Deaths typically occur from acute encephalitis, or brain swelling, when the virus travels to the central nervous system, or pneumonia if it migrates to the lungs. 

Before the current two-dose childhood vaccine’s approval in 1968, there were up to 500 US deaths each year from measles, 48,000 hospitalizations and 1,000 cases of brain swelling. 

Roughly 3million to 4million people were infected every year.

SSPE occurs when the measles virus spreads within the central nervous system. 

After initial infection it remains dormant in the brain before being reactivated, either randomly or through another infection, and causing inflammation that damages neurons over time. 

Measles, pictured here, through direct contact with infectious droplets or through the air (stock image)

Because measles is generally rare due to vaccination efforts, the CDC suspects no more than 10 cases of SSPE are reported every year. 

There are no treatments for SSPE, and the condition can only be managed with supportive care and anticonvulsant drugs to prevent seizures. It generally takes one to three years after initial measles infection for SSPE to become fatal. 

SSPE does not cause symptoms while it lies dormant.

The Los Angeles County Health Department said in the statement: ‘Infants younger than six months are too young to be vaccinated and rely on maternal antibodies and community immunity to reduce their risk of exposure.

‘By getting vaccinated, individuals not only protect themselves but also help shield vulnerable populations — including infants, pregnant people, and those with weakened immune systems — from measles infection.’