The Epidemiological Changes Of Hospitalized Children With Measles From 1961 To 2010

ObjectiveTo understand the changes of the number of hospitalized cases with measles, fatality, seasonal and age distribution in pre-vaccine and vaccine era and to provide epidemical data for the control and elimination of measles.MethodsThe data of hospitalized children with measles aged 0-14 years old in children's hospital of Chongqing Medical University from 1961 to 2010 was statistical analyzed retrospectively.Results(1) With the use of measles vaccine, the number of hospitalized cases with measles decreased, and the percentage of the number of measles to total hospitalized cases decreased from 20.15% in 1961-1964 to 0.64% in 1998-2010. There was an increase significantly in 2007-2008 and the percentage rose to 3.34% in 2007. The number of measles cases began to decrease in 2009. There was no obvious epidemic periodicity to be found.(2) The fatality decreased from 4.07% in 1961-1964 to 0.23% in 1998-2010. There was no statistically significant difference among age groups for the fatality.(3) The gender ratio was 1.46:1 totally, and it increased from 1.26:1 in 1961-1964 to 1.80:1 in 1998-2010. (4) The number of measles peaked in April, February, March-Apirl, May, May in 1961-1964, 1965-1977, 1978-1987, 1988-1997 and 1998-2010, respectively. Since 1998, cases concentrated to April-July and peaked in May. The peak time postponed to June or July in 2007-2008.(5) In pre-vaccine stage, most of measles cases were found among the children aged 0-5 years old. The proportions of measles cases aged 0-8m and 5-14y were lower. In vaccine and EPI stage, the proportion of measles cases aged 0-5y was decreased. The proportion of 0-8m was 7.51%,6.32%,7.41%,32.6%,17.36%,32.45% in 1961-1964, 1965-1977, 1978 -1987, 1988-1997 and 1998-2010 respectively, which was increased gradually(P<0.001). The proportion of 5-14y was 4.84%,5.30%,16.55%,27.20 and 10.51%, respectively. It increased at the beginning of EPI stage and decreased from 1998(P<0.005).(6) Pneumonia was the most common complication of hospitalized children with measles, followed by diarrhea, myocarditis and laryngitis. The incidence of pneumonia decreased by age. The incidence of diarrhea was higher in 0-2 years age group while the incidence of laryngitis was higher in 0-5years age group. The incidence of pneumonia, diarrhea and myocarditis increased gradually from 1993 to 2010.Conclusions1. With the use of measles vaccine, the hospitalized measles cases were decreased. There is no obvious epidemic periodicity to be found. The hospitalized cases may increase dramatically because of the accumulation of susceptible individuals.2. There is more male patient. There is an increasing trend in the proportion of male.3. The fatality decreased gradually.4. The peak time of the measles is postponed. 5. The age distribution changed and the proportion of measles cases aged 0-8month increased.6. Pneumonia, diarrhea, myocarditis and laryngitis are the common complications of measles.