Abstract
Influenza is one of the most important viral diseases with high mortality and morbidity that can have a great impact on public health and economy. To investigate the clinical and epidemiological features of influenza virus A/H1N1, A/H3N2, and B infection in Fars province, southern Iran, in 2015-2019. In this retrospective cross-sectional study, we assessed the archived data of Syndromic Surveillance System of Iran's Health Ministry, allowed access by Communicable Diseases' Unit of Health chancellor of Shiraz University of Medical Sciences, from December 22, 2015 to September 22, 2019. The participants included all patients whose data were recorded as influenza-like illness (ILI) and severe acute respiratory infections/illness (SARI). Influenza viral infection was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). Totally, 1269 patients suspected of influenza were sampled. The mean ± SD of age was 29.40 ± 26.91 years. Fever was the most common symptom (68.6%). The highest incidence was in winter (55.9%). Of 928/1269 laboratory's results which were recorded in the registry, 204 (16.08%) samples were positive and 724 (57.05%) were negative. Among 204 positive results, 191 (15.05%) were influenza type A, and 8 (0.63%) influenza type B. Among patients with definite influenza type A, 34 (2.68%) had H1N1/p subtype, 58 (4.57%) H3N2, and one (0.08%) had other subtypes; however, subtypes were not identified in 7.72% of patients. Six (3.0%) patients with confirmed influenza expired. The incidence of influenza, especially type A, in Fars province, southern Iran is considerable and requires more attention for prevention in health policy programs.
Highlights
Influenza is one of contagious viral diseases caused by an RNA virus from the Orthomyxoviridae family.[1]
During the study period, 1 149 124 patients were referred to 77 Fars province health centers, southern Iran, due to respiratory symptoms, and their data were recorded in the registry system
All 6966 (61%) were suspected of influenza-like illness (ILI) [3,287 (47.2%) males vs. 3,679 (52.8%) females]. Both genders were similar in terms of ILI and severe acute respiratory infections/illness (SARI) (P = 0.425)
Summary
Influenza is one of contagious viral diseases caused by an RNA virus from the Orthomyxoviridae family.[1]. It should be noted that the economic impact of influenza outbreaks is of great importance.[6] The influenza virus infection has different clinical features, and it may not be distinguished from other respiratory viral diseases It is not detectable based solely on symptoms.[7] Correct diagnosis and rapid and appropriate management are important for controlling this disease, which would not be possible without practical laboratory tests.[8] Various tests are available for rapid antigen detection, but confirmation of the influenza viral infection by reverse-transcriptase polymerase chain reaction (RT-PCR)[6] is rapid, costeffective, sensitive and specific.[8,9,10] All positive cases should be considered as influenza, and specific treatment should be started as soon as possible.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
