The hajj is the single largest gathering on the planet, and it involves 2.5 million Muslims from 160 countries converging on the small Saudi city of Mecca. This year, Saudi authorities are concerned that these pilgrims will bring swine flu with them.

Fears are running high that this year’s hajj could prove to be a prime breeding ground for the H1N1 virus. Pilgrims crowd into boats, planes, buses, tents and more. The worshippers pray shoulder to shoulder while continually touching their hands to communal floors and handrails.

Virus outbreaks have proven difficult to manage in past religious gatherings. In July 2008, around 200,000 Catholics from across the globe met in Sydney, Australia, for World Youth Day. This was right in the middle of the Southern Hemisphere’s winter. A major flu outbreak ensued, later spreading through the rest of the world. Also in 2008, Iran considered banning pilgrimages to Mecca because of the flu scare.

Dr. Ziad A. Memish, the Saudi assistant deputy minister for preventive medicine, recently told the New York Times: “We’ve said we won’t turn away anyone who arrives at our borders. But we are recommending to other countries whom they should let come.” 

The Saudi government has urged pilgrims to bring their own surgical masks, hand sanitizers, and to wash their hands frequently. However, hand sanitizers may prove tricky for devote pilgrims, as Islam forbids alcohol. Face masks may also prove difficult for pilgrims. Men can only wear clothing without stitches, and women are forbidden to cover their faces.   

The Saudi government has considered barring anyone who is pregnant, under age 12, over age 65, or suffering from chronic conditions and diseases such as diabetes, chronic lung, heart, liver or nerve disease.

However, banning certain pilgrims may prove difficult. Every Muslim is supposed to make this pilgrimage at some point in his or her life, and some save for years to do so. More than half of all pilgrims are older than 50. Even if this means they will be pushed around the Kaaba in wheelchairs, pilgrims will come.  

With all of these concerns, the Saudi government has turned to the U.S.-led Center for Disease Control and Prevention for help in heading off a potential health crisis. (The CDC has the most experience in dealing with swine flu.) The Saudi government has purchased stockpiles of generic Tamiflu and opened 76 health facilities specifically for the hajj. All medical care for symptoms that pilgrims develop during their visit will be provided free of charge.

Some countries have offered to vaccinate their pilgrims. China has vowed to vaccinate all 12,700 pilgrims. But as the Times points out, Muslims who are making this year’s pilgrimage will not be made a priority group.

Want more? Visit MNN's swine flu headquarters.