Epidemiological peculiarities of seasonal flu morbidity in the Republic of Moldova

Abstract

Introduction. Influenza affects 5-10% of the human population each year and spreads to all geographical areas. The loss of life and economic costs become considerable during the annual flu epidemics and can be enormous during pandemics with new strains. Aim of study. Analysis of multiannual morbidity due to seasonal flu and determination of the causes of the increase and decrease of the incidence in certain periods. Methods and materials. This research is a descriptive observational epidemiological study, in which the data on influenza morbidity were analyzed. The following were used as information sources: Form 2, Epidemiological Bulletin of Infectious Diseases for the years 2004-2021. The following epidemiological indicators were analyzed: the incidence of cases in the republic and in the municipality of Chisinau, the incidence according to the living environment and age groups. Results. Analyzing the multiannual flu morbidity in the Republic of Moldova and Chisinau municipality during the years 2004 - 2021, we found that during the 2004-2008 years, both in Chisinau municipality and in the Republic, the level of influenza morbidity had close values. During this period, in the municipality of Chisinau, the epidemic years were 2005 and 2007, the recorded morbidity was 185,38 ‱ and 201,99 ‱, respectively. Both in Chisinau and in the republic, the year with the highest morbidity was 2009. During the 2012-2021 years, the influenza morbidity in Chisinau municipality was higher compared to that at the republic level. The highest incidence in this period was recorded in 2020 - 250.82 ‱. The lowest morbidity, similar to that of the republic, was recorded in 2021 – 5,04 ‱. Depending on the area of residence, urban and rural, during the years 2004-2021, the influenza morbidity was higher in urban areas compared to rural areas. The years with the highest incidence were 2013, 2015 and 2020, both in urban areas – 86,54 ‱, 71,86 ‱, 117,08 ‱, and in rural areas – 34,50 ‱, 20,56 ‱ and 26,55‱. Depending on the age groups, children 0-17 years and adults, we found a higher incidence of diseases among children with an average over the entire period of 262,69 ‱, compared to adults – 98,66 ‱. Among the children, the most affected by the flu were those aged 7-17 years - 2.63, followed by those aged 3-6 years - 2.60 and 0-2 years - 1.86. Conclusion. The highest flu morbidity in the analyzed period was recorded in urban areas and in children. Due to the COVID-19 pandemic and anti-pandemic restrictions, in 2021 there was a sharp decline in influenza morbidity in all age groups and living environments.