Viral aetiology of severe acute respiratory illness among patients admitted during the 2022 peri-Hajj period.

Introduction: Severe acute respiratory illness (SARI) among pilgrims continues to be an important healthcare issue. The aim of this study was to describe the viral aetiology of patients admitted to hospitals in the holy cities of Makkah and Madinah during the 2022 peri-Hajj period.

Methods: This is a retrospective analysis of patients admitted to hospitals with SARI. Patients were tested with multiplex polymerase chain reaction for the most common viral aetiologies.

Results: In total, 179 cases of SARI were identified during the study period. Of these, 101 (56.4%) were males, 78 (43.6%) were females, and 78 (43.6%) were Saudi. The mean age was 58.60 years (standard deviation 20.5) years. The most common age group was ≥65 years (=68, 36%), followed by 55-59 years (=37, 19%). The most common comorbidities were diabetes mellitus (=67, 36%), hypertension (=65, 35%) and chronic lung disease (=34, 18%). Eighty-five (47.5%) patients tested negative and 94 (42.5%) tested positive for various viral aetiologies. The most frequently detected viruses were severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) (=28, 15%) and influenza (=22, 12%); of the influenza cases, 16 were influenza A (6 (43%) were H3N2), and six were influenza B. The only case of Middle East respiratory syndrome coronavirus (MERS-CoV) was in a citizen, and none of the visitors or residents had MERS-CoV. Of the total cases, 27 (14%) died during the follow-up period. In a binary regression analysis, only age was associated with mortality (=0.002).

Conclusion: The most commonly detected viruses among patients admitted to hospital with SARI were SARS-CoV-2 and influenza. It is important to continue surveillance of admitted and non-admitted patients in different Hajj periods to identify any shift in the aetiologic agents.