Eosinophilic meningitis is endemic in Thailand. There is limited data on its epidemiological data and seasonal variation. This study reviewed a 2017 annual report of the National Disease Surveillance, Bureau of Epidemiology, Department of Disease Control, Ministry of Public Health, Thailand. The annual report comprised of numbers of patients, morbidity rate, mortality rate, age group, nationality, and occupations of patients diagnosed with eosinophilic meningitis by months, a public health zone, and provinces. There are currently 13 public health zones throughout Thailand and 76 provinces plus one
capital city; Bangkok. There were 189 patients diagnosed with eosinophilic meningitis throughout Thailand in 2017. All patients were Thai. The common age groups were between 25 and 54 years (129 patients; 68.25%). The majority of patients
were male (115 patients; 60.85%), agriculturists (88 patients; 46.56%) and lived in the northeastern part of Thailand (182
patients; 96.30%). The mortality rate was zero. Loei province had the highest number of patients and morbidity rate of
Thailand at 63.49% and 18.85/100,000 population. The most common season for eosinophilic meningitis in Thailand was a
rainy season (90 patients; 47.62%). Only differences by provinces were significantly related to numbers of eosinophilic
meningitis by seasons (p-value = 0.004). In conclusion, the northeastern part of Thailand particularly Loei province is still
endemic for eosinophilic meningitis. The infection is more prominent in working-aged male in the rainy season.

Keywords: Angiostrongylus cantonensis, Morbidity, Mortality