ABSTRACT
The annual Hajj pilgrimage to Mecca brings over two million people together in a small confined area. Respiratory involvement is the most common disease during this ceremony, and up to now no unique cause has been identified. The present study was conducted to determine the incidence and types of respiratory diseases and their associated etiologic agents. During this prospective study, seroconversion was assessed for bacteria, viruses and fungi on 170 Iranian pilgrims prior to departure and 2 weeks after convalescence and returning from the Hajj pilgrimage. Meanwhile, sputum specimens of 252 patients were cultured. The following viruses were detected: influenza type A and B [21.5%], adenovirus [36.2%], and RSV [1.9%]. Among bacteria isolates, beta-haemolytic Streptococcous [9.7%], Haemophilus species [9.1%], Gram negative bacilli [20.6%], Legionella pneumophila [6.3%], Mycoplasma pneumonia [0.8%], and Chlamydia [32%] were more common, however, no fungal seroconversion was noted. We suggest administration of Fluvaccin for high risk groups, adenoviral vaccine for volunteer pilgrims, erythromycin or azithromycine for empiric bacterial therapy, and Oseltamivir or Zanamivir for prophylaxis or treatment of influenza like illness