Differences in clinical characteristics of severe acute respiratory infections’ cases caused by influenza virus in Montenegro 2014–2019

Abstract

Background: Seasonal influenza is an acute respiratory infection caused by worldwide circulating influenza viruses. Influenza virus might cause numerous complications including secondary infections, exacerbation of pre-existing disease or lethal outcome. Describing clinical characteristics of the severe acute respiratory infections (SARI) cases caused by different subtypes of influenza virus in different age groups during the 5 seasons 2014–2019 in Montenegro. Methods and materials: Descriptive epidemiological method was used for this study. Data on number of SARI cases and laboratory confirmed cases of influenza for the referring period were obtained from Institute of Public Health Montenegro. SARI surveillance units are departments for infectious diseases, pulmonary diseases and intensive care units in chosen hospitals. World Health Organisation's definition of SARI case is used. Every SARI case is sampled with respiratory swab tested for influenza by polymerase chain reaction. During the hospitalization of SARI case data on clinical characteristics are collected. Results: During the 5 referring seasons 196 SARI cases were registered (60.2% males, 39.8% females) with 66.1% of cases from Central Region. Almost half (45.9%) cases were 30–64 years old and 38,8% were older than 65. Only 8 patients were vaccinated. Results are shown in Table 1.Table 1Clinical characteristics of SARI casesAdults (% of cases, aged 30-64)Elderly (% of cases aged ≥65)SymptomAH3AH1pdm09AunsupBYamagataAH3AH1pdm09AunsupBYamagataFewer88,8994,87100,0076,9283,3386,3666,6761,54Dyspnoea77,7889,74100,0061,54100,0095,45100,0084,62Pneumonia55,5682,05100,0053,8566,6795,4577,7876,92ARDS0,0043,5925,007,690,0033,3311,1115,38Comorbidity55,5641,0350,0025,0091,6781,0062,5050,00Mechanic ventilation33,3343,5950,0038,4683,3363,6455,5638,46 Open table in a new tab Conclusion: Influenza virus causes more severe clinical presentation among patients with comorbidity and elderly. Study has shown that immunization is one of the best measures of flu prevention.