Epidemiological And Clinical Characteristics of Measles Cases in Taiwan: An Age–Period–Cohort Analysis, 2002–2019

DOI: 10.6524/EB.202404_40(8).0001

Xiang-Ting Huang1*, Wei-Ju Su2, Yu-Fang Tsai1, Hsiao-Ping Tung1, Chi-Tai Fang3,4,5

2024 Vol.40 NO.8

Correspondence Author: Xiang-Ting Huang1*

  • 1Taipei Regional Center, Centers for Disease Control, Ministry of Health and Welfare, Taiwan
  • 2Division of Acute Infectious Diseases, Centers for Disease Control, Ministry of Health and Welfare, Taiwan
  • 3Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taiwan
  • 4Division of Infectious Diseases, Department of Internal Medicine, National Taiwan University Hospital, Taiwan
  • 5Ministry of Health and Welfare and National Taiwan University Infectious Diseases Research and Education Center, Taiwan


        Measles is regarded as a disease that can be fully eradicated and controlled by vaccination. However, measles outbreaks have been observed since 2018 in high-income countries with complete measles vaccination programs, and the infection of measles in young adults is increasing.
        A retrospective cohort study was conducted by dividing Taiwanese patients diagnosed with measles between 2002 and 2019 into three groups according to the different vaccination policy periods. Specifically, (1) Cohort A: born before August 1976 (no mass immunization); (2) Cohort B: born between September 1976 and September 1990 (when infants were recommended to receive 2 doses of MV plus 1 dose of MMR); and (3) Cohort C: born after October 1990 (when infants are recommended to receive at least 2 doses of MMR). Analysis was conducted to explore the age of onset, differences between the cohorts, changes in the incidence rates across different periods, and the clinical symptoms and laboratory characteristics of patients with breakthrough infection. 
        Among the confirmed measles cases in Taiwan over the past 18 years, 46.6% belonged to Cohort B. Among the 136 patients aged 18–39 years who were diagnosed with measles between 2018 and 2019, 83(61%) were IgM (-)/IgG (+) in acute-phase sera, 2 patients caused an outbreak. Moreover, 72 (53%) cases did not present cough, coryza, or conjunctivitis. Statistical significances were observed between patients with primary infection and those with failed vaccination in the clinical symptoms and acute phase serum antibody results. The RT-PCR tests proved enable to verify the measles infections accurately.
        Similar to other countries with high vaccination rates and low measles incidence, adults with breakthrough infections have been seen in Taiwan in recent years. In this study, we performed analysis on the age–period–cohort allowed to identify individuals with high risks of measles infection and provide suggestions on determining vaccination targets and schedules.