Quantifying the long-term effects of measles infection-a retrospective cohort study.

OBJECTIVES

To assess whether measles infection has an impact on the rate of non-measles infectious diseases over an extended period.

METHODS

This retrospective matched cohort study included 532 measles-diagnosed patients who were exactly matched with 2128 individuals without a previous measles diagnosis. Adjusted OR for any all-cause infectious diagnosis and any viral infection diagnosis ≤2 years after measles diagnosis between the measles and control groups was obtained from a conditional logistic regression model. The Cox proportional hazards model was used to estimate the hazard ratio.

RESULTS

Previous measles virus (MeV) exposure was associated with an increased risk for all-cause non-measles infectious disease diagnosis (OR: 1.83, 95% CI: 1.26-2.64, p 0.001), with 492 diagnoses in the MeV-exposed group and 1868 diagnoses in the control group. Additionally, previous MeV exposure was linked to a higher risk of viral infection diagnosis (OR: 1.23, 95% CI: 1.01-1.59, p < 0.05), with 302 viral infection diagnoses in the MeV-exposed group and 1107 diagnoses in the control group. The hazard ratio for viral diagnosis in the MeV-exposed group compared with the control group was 1.54 (95% CI: 1.18-2.02, p < 0.001).

DISCUSSION

Individuals diagnosed with measles had a moderately increased risk of being diagnosed with all-cause non-measles infectious disease or viral infection. This observational individual-level study supports previous ecological and individual population-level studies.