Background: The data on the seasonality of respiratory viruses helps to ensure the optimal vaccination period and to monitor the possible outbreaks of variant type.Objectives: This study was designed to describe the molecular epidemiology and seasonality of acute respiratory infection (ARI)-related respiratory viruses in the United Arab Emirates (UAE). Methods: Both upper and lower respiratory specimens were collected for the analysis from all the patients who visited the Sheikh Khalifa Specialty Hospital (SKSH) with ARI for over 2 years. The multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR) test was used to detect respiratory viruses, which include human adenovirus, influenza virus (FLU) A and B, respiratory syncytial virus, parainfluenza viruses, human rhinovirus (HRV), human metapneumovirus, human enterovirus, human coronavirus, and human bocavirus. Results: A total of 1,362 respiratory samples were collected from 733 (53.8%) male and 629 (46.2%) female patients with ARI who visited the SKSH between November 2015 and February 2018. The rRT-PCR test revealed an overall positivity rate of 37.2% (507/1362). The positive rate increased during winter; it was highest in December and lowest in September. FLU was the most frequently detected virus (273/1362 [20.0%]), followed by human rhinovirus (146/1362 [10.7%]). The FLU positivity rate showed two peaks, which occurred in August and December. The peakto-low ratio for FLU was 2.26 (95% confidence interval: 1.52-3.35).
Conclusions:The pattern of FLU in the UAE parallels to that of temperate countries. The trend of the small peak of FLU in the summer suggests a possibility of semiseasonal pattern in the UAE. K E Y W O R D S human influenza, molecular epidemiology, respiratory tract infections, seasons, United Arab Emirates (UAE)