SSPE Risk After Measles Infection Beyond Age 10
Yes, people can develop SSPE if they contract measles after age 10, though the risk is substantially lower than in younger children—approximately 16 times lower than measles contracted before age 1. 1
Age-Related Risk Stratification
The risk of SSPE following measles infection follows a clear age gradient:
- Highest risk occurs when measles is contracted under age 2, with nearly half of SSPE cases having had measles during this period 1
- Measles under 1 year of age carries a risk 16 times greater than measles contracted over age 5 1
- The overall calculated risk of SSPE following measles infection is approximately 4.0 per 100,000 cases, but this increases dramatically to 18 per 100,000 for measles contracted before age 1 2
- Children who contract measles when less than 5 years of age have the highest incidence of SSPE (6.5 to 11 per 100,000 measles cases) 3
Critical Clinical Context
SSPE remains possible at any age of measles infection, but with important caveats:
- The disease typically appears years after the initial measles infection, with a median interval of approximately 8 years between measles and SSPE onset 1
- Survival time is actually shorter when measles occurred at older ages (over the mean age of 2.5 years), suggesting different disease kinetics in older-onset cases 1
- SSPE is a rare but fatal late complication that can appear in immunologically normal individuals years after infection 4, 5
Prevention Remains Universal
Regardless of age considerations:
- Measles vaccination is the only effective prevention strategy for SSPE and has led to near elimination of cases in countries with high vaccination coverage 4, 6
- The risk of SSPE after measles vaccine is only 0.14 per 100,000 doses compared to 4.0 per 100,000 measles cases—a 28-fold reduction 1, 2
- MMR vaccine definitively does not increase SSPE risk, and when rare cases occur in vaccinated individuals, evidence indicates they had unrecognized measles infection before vaccination 4, 6
Common Pitfall to Avoid
Do not assume that older children or adults are immune to SSPE risk—while the risk decreases with age at measles infection, it never reaches zero, and until measles is eradicated worldwide, individuals in all age groups remain at risk 3, 7