Analysis Of The Infection Rate Of Measles In Qingdao

Measles is an acute respiratory infectious disease caused by Measles Virus?MV?.Measles virus is a single-stranded negative RNA virus transmitted through air and direct contact^[1].Measles is a class b infectious disease,which is highly contagious and spreads rapidly.By taking various control measures,the incidence of measles in China has been greatly reduced,but it is still one of the countries with the highest annual incidence of measles in the world.In 2016 alone,the incidence of measles in China was as high as24,820 cases^[2].The epidemic of measles seriously harms human health,which is of great significance for its control and elimination.Compared with countries such as Europe and the United States,there are few studies on the dynamic transmission characteristics of measles in China.It is necessary for us to deeply explore measles,study the transmission of the disease,and help us develop strategies to prevent and control measles.In this paper,we took measles in Qingdao as an example to estimate its transmission rate and transmission seasonality for two stages by TSIR?Time Series Susceptible Infected Recovered?model:pre-vaccination era?1951-1964?and recent 15 years?2000-2014?.We explored the possible influencing factors of seasonal changes in transmission rate seasonality before and after vaccination.Moreover,this paper compares it with another child susceptible disease?hand,foot and mouth disease?and a larger range?Shandong Province?measles epidemic,and explores its connections and differences.The results showed that the measles transmission rate in Qingdao had significant annual seasonality in both stages.In recent 15 years,the seasonal peak of the measles transmission rate in Qingdao has obviously shifted from December to February,when Chinese usually celebrate Chinese New Year.The transmission seasonality for measles in Qingdao is far greater than the seasonality of measles transmission in other countries.Study the transmission rate seasonality has important reference value for developing vaccination strategies.