[P1-18] Acute encephalitis and encephalopathy surveillance in Kawasaki city, Japan, 2007-2016
[Purpose] To describe the annual trend of acute encephalitis/encephalopathy, and reveal the nationwide estimates by using notifiable surveillance data and microbiological examination data in Kawasaki city, Japan.
[Methods] Between Jan 2007 to Oct 2016, we received 90 reports of acute encephalitis/encephalopathy. We investigated the characteristics by onset, age, sex, causative agents by using polymerase chain reaction test (PCR) and/or microbiological culture and compared with national data.
[Results] Of 90 cases, including 56 males, 77 cases were reported as a notifaiable disease. 63 cases were under 15 years old, including 41 cases with under 5 years old. Reported number of cases were gradually increasing year by year during 2011-2014. The rate remained stable from 1.2 to 1.3 per 100,000 population in 2014-2015, subsequently increased to 1.6 per 100,000 population in 2016. Assuming that the prevalence rate is 1.2-1.3 per 100,000 population, the proper number of cases were estimated approximately 1600 in nationwide. Even though 89 cases were tried to isolate the causative agents, the pathogen in 33.7% of cases remained unknown. Influenza (detected in 7 cases, diagnosed in 4 cases without detection/isolation) constitutes the most common cause of acute encephalitis/encephalopathy mainly in winter months. Enteroviruses, such as coxackievirus and human parechovirus, were detected in 5 cases predominantly in summer, followed by 3 adenovirus cases in winter. Human herpes viruses were detected in 32 cases on a year-round basis.
[Conclusions] It is necessary to know the local trend and connect the surveillance data with information of pathogenic agents.
[Methods] Between Jan 2007 to Oct 2016, we received 90 reports of acute encephalitis/encephalopathy. We investigated the characteristics by onset, age, sex, causative agents by using polymerase chain reaction test (PCR) and/or microbiological culture and compared with national data.
[Results] Of 90 cases, including 56 males, 77 cases were reported as a notifaiable disease. 63 cases were under 15 years old, including 41 cases with under 5 years old. Reported number of cases were gradually increasing year by year during 2011-2014. The rate remained stable from 1.2 to 1.3 per 100,000 population in 2014-2015, subsequently increased to 1.6 per 100,000 population in 2016. Assuming that the prevalence rate is 1.2-1.3 per 100,000 population, the proper number of cases were estimated approximately 1600 in nationwide. Even though 89 cases were tried to isolate the causative agents, the pathogen in 33.7% of cases remained unknown. Influenza (detected in 7 cases, diagnosed in 4 cases without detection/isolation) constitutes the most common cause of acute encephalitis/encephalopathy mainly in winter months. Enteroviruses, such as coxackievirus and human parechovirus, were detected in 5 cases predominantly in summer, followed by 3 adenovirus cases in winter. Human herpes viruses were detected in 32 cases on a year-round basis.
[Conclusions] It is necessary to know the local trend and connect the surveillance data with information of pathogenic agents.