Methods: A quasi-experimental trial study was conducted to compare the effectiveness of nasal rinsing between two groups. The intervention group was instructed to perform nasal rinsing during ablution, while the control group was not asked to do nasal rinsing. Both groups were provided progress diaries to record the symptoms of respiratory tract infection, including cough, rhinorrhoea, nasal blockage, fever, and sore throat, as well as thick phlegm, shortness of breath, epistaxis, and changes in sense of smell. The groups were also instructed to record any visits to clinics for their symptoms throughout their stay in Makkah for the Hajj ritual.

Results: The study showed that nasal rinsing significantly reduced the symptoms of cough, rhinorrhoea, and nasal blockage. The intervention group had an increased number of visits to healthcare facilities for treatment, when compared to those of the control group. There were no significant differences in the groups regarding the symptoms of fever and sore throat.