ObjectiveTo investigate the epidemiological characteristics of measles complicated with pneumonia cases in Shanghai in 2015-2020.

MethodsCase information was acquired from the measles surveillance information reporting and management system. Data of complications was recorded according to the medical information of the measles cases. The measles complicated with pneumonia cases were then characterized.

ResultsFrom 2015 through 2020， a total of 1 402 measles cases were notified in Shanghai， with an incidence rate of 0.96/100 000. Among them， 104 cases were complicated with pneumonia， with a complication proportion of 7.42%. The annual incidence of measles complicated with pneumonia was determined to be 0.07/100 000. There was no significant difference in the proportion of measles cases complicated with pneumonia across years （P=0.871）. Among the measles cases complicated with pneumonia， 62.5% were children aged 3 years or younger， which differed significantly with those without pneumonia （20.0%） （P<0.001）. Moreover， 64.4% had been to hospital 7-21 days prior to the onset of measles， compared to those without pneumonia （41.8%） （P<0.001）. Highest body temperature and the proportions of coughing， catarrhus， conjunctivitis， Koplik spot and other complications in the measles cases complicated with pneumonia were significantly higher than those in non-complicated cases （P<0.05）.

ConclusionIncidence of measles complicated with pneumonia is positively correlated with the overall incidence of measles. Measles cases complicated with pneumonia are mainly young children， with underlying diseases， and more severe symptoms. Therefore， it is necessary to reduce the overall incidence of measles， and pay attention to the vaccination and routine protection of young children with specific health conditions.