Trends of Seasonal Influenza Incidence among the Population of Abha, Saudi Arabia During 2019

Background: Influenza is one of the infections in which a specific pattern is observed according to seasons which result in severe forms of disease. By providing regular and extensive quality in epidemiological studies, the surveillance system can help in reducing the threat to public health posed by influenza that eventually minimizes the effect of illness. They also help in reporting the health ministry about the relevant information as an aid to reduce the impact of disease on public health.

Objective: To assess the incidence of seasonal influenza in Abha City, Saudi Arabia.

Methods: This surveillance report conducted among citizens of Abha, Saudi Arabia, 2019. It is based on sentinel surveillance and case-based data collection of laboratory-confirmed cases through electronic health records. All data were obtained from the department of infectious diseases of public health department in Aseer health directorate.

Results: The total reported positive cases for influenza viruses were 808 (22.30%) patients in the city of Abha for the year 2019, among them 435 males and 373 females (F= 9.5149; P=0.002038) which 665 (82.3%) were typed as influenza A and 143 (17.7%) as influenza B. (F= 674.46; P=0.001). The prevalence of the disease is commonly seen in the age group of 5-15 (42.35 %) with a mean age of 15.45±4.50 followed by 16 to 50 years age (37.45%) and 51-65 age group (10%). There was no death registered among these cases. In February maximum cases were found, whereas in June and July minimum cases were recorded. The influenza positivity rate showed one primary peak and three secondary peaks that were recorded in February and January, March and December.

Conclusion: Importance of conducting effective epidemiological surveillance for influenza virus in various regions in Abha specially in winter season with a peak in the month of February.