Epidemiological characteristics of pertussis in Ji'an City in 2014 -2024

Objective To explore epidemiological characteristics of pertussis in Ji'an City from 2014 to 2024 , providing a scientific basis for formulating prevention and control strategies.Methods The data of pertussis cases and immunization history in Ji'an City from 2014 to 2024 were collected, and the epidemiological characteristics of pertussis were analyzed by descriptive epidemiological method.Results There were 1133 pertussis cases reported in Ji'an City between 2014 and 2024, for an average annual incidence of 2.17/100,000.The incidence showed a fluctuating upward trend, ranging from 0 to 23.07/100,000 over the years, and the reported incidence in 2024 came up to 23.07/100,000 . The average annual reported incidence rate in all counties (urban areas) ranged from 0.68/100,000 to 5.60/100,000. Cases show a high incidence in spring and summer, with 81.64% (925 cases) occurring from March to July. The average annual reported incidence rates for males and females were 2.48/100,000 and 1.84/100,000 respectively, showing difference between males and females. Incidences per 100000 for <1 -, 1–4-, 5–9-, and ≥10- years old were 52.76, 5.13, 13.20 and 0.27, respectively. The reported incidence rate for ≥5 years old shows a fluctuating increasing trend , increasing from 0 in 2014 to 15.40 /100,000 in 2024; the cases were mainly concentrated in students and scattered children (74.85%) . Among the no immunization history,51.05% (121/237) were under the age of vaccination.92.52%（507/548）of 5-9 years old had completed the whole course of vaccination.84.47%(957cases) were laboratory-diagnosed. Conclusion The incidence rate of pertussis in Ji'an City showed an increasing trend from 2014 to 2024, with higher incidence between <1,5-9 years old, and more patients over 5 years old. We should strengthen pertussis surveillance and training of medical staff, optimize the immunization strategies, strengthen vaccination, and reduce the risk in infants and students.