The Trend of Meningitis in Guilan Province, Northern Iran During 2011-2022: An Ecological Study

Background and aims: Despite the availability of vaccines, antibiotics, and healthcare services, meningitis is a serious cause of morbidity and mortality worldwide. Thus, this study investigated the incidence of meningitis and identified areas with the highest incidence in Guilan. Methods: This study calculated the cumulative incidence of meningitis (confirmed and probable cases) and fever and neurological symptoms syndrome per 100,000 population each year. Join point regression analysis was used to identify noticeable changes in the trend of disease, and ArcGIS software was employed to determine high-risk areas. Results: Overall, 653 cases of syndrome were reported during 2011-22, of whom 404 (61.87%) were confirmed and probable cases of meningitis. The age of 148 (36.63%) meningitis patients was less than 5 years, and 255 (63.12%) were male. The outcome of death was reported in 11.54% of confirmed cases and 6.28% of all cases. Joinpoint regression analysis revealed significant decreasing trends in the incidence of fever and neurological symptoms post-2018 across all age groups (APC: -37.45%, P<0.05), with a notable decrease in children<5 (APC: -54.03%, P<0.05). Additionally, a significant reduction was found in those over 5 years after 2015. For meningitis cases across all ages and children under 5, non-significant trends included a breakpoint in 2019, with a subsequent decline. Meningitis incidence demonstrated a nonsignificant decreasing trend among individuals over 5 years throughout 2011-2022. Conclusion: The annual incidence of meningitis and syndrome in Guilan was lower than the average in the whole country, but the case fatality rate was higher.