Analysis Of The Epdemic Feature Of Measles From 2000 To 2005 On Xinghualing District, Tiayuan City

Objective: To explore the epidemiological characteristics and population immunity status of the measles on Xinghualing district, Taiyuan city, and find out susceptible population, analyze the trend of the disease incidence and the corresponding reason, offering the epidemiological evidence for further controlling the disease and working out the related strategy. Methods: All 278 confirmed measles cases from 2000 to 2005 were collected. Descriptive epidemiological analysis was conducted including calculating incidence rate each year, describing distributions on season, age, occupation, and so on. Besides, vaccine inoculation status were investigated and data was analyzed.Results: (1) During 2000 to 2005, there are 278 measles cases was diagnosed, the average reported incidence rate was 8.81/100,000. The incidence varied from 0.59/100,000 to 2.90/100,000 during 2000~2003, it increased to 20.12/100,000 on 2004 and to 24.61/100,000 till 2005. An significant increasing trend was shown. (2) The age distribution shown that most cases are children younger than 5 years old, which accounts for 46.76%, while proportion on 6~11 years old, 12~17 years old, and older than 17 years old were 29.14%, 6.12% and 17.99%, respectively. Within the group younger than 5 years old, we found that distribution proportion for younger than 8 months, 8 months to 1 years old, 1~2 years old and 3~5 years old children were 13.67%, 3.24%, 12.95%, and 16.91% respectively. The cases for younger than 8 months children increased over 6 years, while the incidence are stable for 8 months to 1 years old children. Cases between 1 to 11 years old increase in 2004, cases older than 12 years old increased in 2005. The age distribution varied hugely between high incidence year and low incidence year, especially for older age group. During 2000 to 2005, the proportion for measles cases within the group younger than 5 years old children was decreased gradually, while it was increased gradually in 6～11 years old and older than 17 years old children (3) Cases occurred in every season, while more frequently in winter and spring. (4) For occupational distribution, we found that disperse resident children accounts for 39.12% all cases. Students, nursery school children and adults accounts for 27.70%, 14.39% and 18.7% respectively. (5) 9 cases were from floating population, 8.41% of all diagnosed cases. (6) Among all 278 cases, 46 cases (16.55%) didn't inoculate the vaccine, 137 cases have unknown inoculation history, no full inoculated cases were found.Conclusions: The main reason of the increase of measles is that planned immunity declined. The results implied that the disease infection on <8 months infant may be related with IgG level from placenta. For 6~11 years old children, the infection may be associated with low repeat follow-up inoculation. The change on infection age may caused by the accumulation on susceptible...