Epidemic encephalitis B (Japanese encephalitis, I), referred to as Japanese encephalitis, is an acute neurological disease caused by infection with Japanese encephalitis virus through mosquito bites. From2008In China, the Japanese encephalitis vaccine was included.15Children under the age of planned immunization management, the number of Japanese encephalitis cases in children has dropped sharply, but the number of adult Japanese encephalitis cases has increased, and there have been many adult Japanese encephalitis outbreaks in northern China. In addition, Japan, South Korea, Malaysia and other countries also have a large number of adult-type Japanese encephalitis, adult-type Japanese encephalitis has become a public health problem of concern at home and abroad.

2023Year12The Chinese Journal of Experimental and Clinical Virology of the Chinese Center for Disease Control and Prevention published a review article entitled "Adult Japanese Encephalitis: New Challenges for Prevention and Control of Japanese Encephalitis", which introduced the epidemic status of adult Japanese encephalitis at home and abroad, and discussed the related issues of adult Japanese encephalitis prevention and control.

Epidemiological characteristics of adult encephalitis B in China

Multiple outbreaks of adult encephalitis B have occurred in China.2006Year7~8An epidemic of adult viral encephalitis was reported in Yuncheng City, Shanxi Province, China in January, which is the first outbreak of adult Japanese encephalitis reported in China and even in the world.2013In Shandong and Hebei provinces in northern China, there was an outbreak of adult-type Japanese encephalitis.2017and2018Gansu Province has experienced since1958The largest outbreak of encephalitis B since.2018An outbreak of adult encephalitis B occurred in the summer of Ningxia.

Epidemiological characteristics of Japanese encephalitis in Chinese adults: (1) The north is the high incidence area of adult encephalitis B.15Cases of encephalitis B in the age group above the age group are mainly distributed in the area north of the Yangtze River, especially in areas larger40Cases in the age group are mainly concentrated in areas north of the Yellow River, including Gansu, Shanxi, Shaanxi, Henan, Hebei, Shandong and Ningxia, the most obvious of which is Shanxi Province.(2）40Age group over the age of adult type JE high incidence population.2006 Year and2005years compared to more40 The number of cases in the age group over the age168.62%,2013Year and2012Compared to the year increased394.16%。2018reported cases in,40People over the age64.0%。(3) The prevalence of adult JE was delayed compared to the South.2004—2014analysis of je cases in,40The number of cases of encephalitis B in the age group above the age group is Shanxi, Shandong, Henan, Hebei, Shaanxi, Gansu, etc. north of the Yangtze River.6Most provinces, the peak incidence is8~9month.9month and10The incidence of adult encephalitis B cases was significantly higher than that of other age groups.

There was no significant difference in clinical manifestations between children and adults, but patients with other diseases/The prognosis of elderly patients is poor.Shanxi Yuncheng Second People's Hospital in2006Admitted during the epidemic of Japanese encephalitis in45cases of encephalitis B patients,40All patients over the age of both basic diseases, compared with children's cases, hospitalization time is longer, the prognosis is worse. Affiliated Hospital of Sichuan University2011Year2018admitted during the year50Analysis of the condition of patients with encephalitis B showed that,50age group and14~50The clinical symptoms of the age group were basically similar, greater50Mortality and long-term disease rates are high, and most adult patients require intensive care. In addition, it is necessary to be alert to the occurrence of Guillain-Barré syndrome in Japanese encephalitis virus infection.

Prevention and control strategy of adult encephalitis B

Japanese encephalitis is a vaccine-preventable disease, and vaccination of inactivated Japanese encephalitis vaccine or live attenuated vaccine can effectively prevent Japanese encephalitis virus infection.Adhere to the Immunization Program for Japanese Encephalitis VaccineAlthough the incidence of Japanese encephalitis in children has decreased in recent years, it is still a long-term task for the prevention and control of Japanese encephalitis in China.To strengthen the study of adult Japanese encephalitis vaccination：2008People who were not fully vaccinated against Japanese encephalitis before the year of birth will gradually become candidates for adult Japanese encephalitis patients, and vaccination against Japanese encephalitis is an effective measure to reduce the occurrence of adult Japanese encephalitis cases.WHOThe Centers for Disease Control and Prevention of the United States recommends that people who travel from non-epidemic areas to epidemic areas of Japanese encephalitis be vaccinated against Japanese encephalitis.

In addition, the ecological environment of Japanese encephalitis should be improved, and pig farms should be kept away from the population, so as to reduce the local mosquito Japanese encephalitis virus infection rate, and then reduce the risk of local people infected with Japanese encephalitis virus. Strengthen the etiological surveillance of encephalitis B, focus on the conversion of dominant genotypes, focus on gene5Type B encephalitis virus is a long-term work to control B encephalitis in the future.

Summary

Japanese encephalitis is a natural focus disease, Japanese encephalitis virus will not be eliminated in nature, Japanese encephalitis vaccine is an important measure to prevent and control Japanese encephalitis. At present, the domestic application of Japanese encephalitis vaccine has inactivated vaccine and live attenuated vaccine, are suitable8Children and adults older than months. In view of the current high incidence of Japanese encephalitis in adults, it is recommended that high-risk groups receive Japanese encephalitis vaccine before the epidemic season.

References:

1.Yin Qikai,Wang Huanyu,Liang Guodong.Adult encephalitis B: A new challenge for prevention and control of encephalitis B[J].Chinese Journal of Experimental and Clinical Virology, 2023, 37(06): 571-577.