A Study On The Imported Risk And Meteorological Factors Of Dengue Fever Based On Dynamic Model In Guangdong Province

Objective:In recent years,the epidemic trend of dengue fever has become increasingly severe and has been a major concern in Guangdong Province.Imported cases are the main factor causing dengue fever in Guangdong,the purpose of this study is to explore the impact of temperature changes on dengue fever,and the driving mechanism of population movement on a large scale（between Southeast Asia and Guangdong Province）,as well as the imported risk of different countries.Furthermore,we aim to explore the development of dengue fever under different prevention and control strategies.Methods:Firstly,the dengue fever case data,meteorological data and flight data of Guangdong Province and Southeast Asian countries in 2010-2019was collected and described statistically.Secondly,a mosquito-borne dynamic model was established to analyze the suitability of mosquito in each city of China.Then,the trend of R₀ at different temperatures was calculated and analyzed by using the dengue transmission dynamic for the outbreak stage,and the incidence of dengue fever in Guangdong Province was simulated.Finally,a dengue fever transmission dynamics model including imported cases was established to analyze the risk of different countries in Southeast Asia and the incidence of dengue in Guangdong Province under different prevention and control measures.Main results:（1）According to the mosquito-borne dynamic model,the parameter expression of the basic offspring number₈)was obtained.The result showed that the temperature range for mosquitoes to survive under different humidity groups was slightly different and the most suitable temperature was about 29.5℃.The result also showed that the temperature in each month of Guangdong Province was suitable for the growth of mosquitoes,which may be one of the factors that cause dengue fever to spread widely in Guangdong.（2）The results indicated that temperature changes had a significant impact on the incidence of dengue fever.And when the temperature increases by 1℃,it’s promotion for dengue fever was most effective and could increase 40.7%（95%CI:33.2%～48.2%）.（3）According to the risk analysis of the imported countries in Southeast Asia in 2019,Cambodia,Thailand,Malaysia,Vietnam,etc,were ranked by country risk.With different prevention and control strategies,only controlling the imported cases and the mosquitoes could reduce the cases of dengue fever,and combination of the control strategies was more effective.For the prevention and control of imported cases in different periods,the earlier measures of imported cases were taken,the fewer dengue cases were in Guangdong,and the best control time was June.Conclusions:Temperature changes have different effects on the incidence of dengue fever,and it will promote the development of dengue fever.Imported cases from Southeast Asia country play a decisive role in the epidemic of Guangdong Province,and the time of control is also the key factor in dengue prevention and control.The results can provide scientific guidance for the prevention,control and risk assessment of dengue fever in Guangdong Province.