MINA, Saudi Arabia - The Saudi health minister said Sunday five people died from the H1N1 flu virus during the Hajj, which as the largest annual gathering of people in the world is considered by health experts as an ideal incubator for the virus.

Speaking on the final day of the Islamic pilgrimage, Abdullah al-Rabeeah said authorities recorded 73 cases -- including the five deaths -- of H1N1, commonly known as swine flu, during the pilgrimage. He said only 10 per cent of the some 3 million pilgrims were vaccinated against the virus.

"Our safety precautions have secured a very successful and safe hajj for pilgrims from around the world with no infectious disease outbreaks," al-Rabeeah said.

Saudi officials, along with American and international health experts, worked to curb any outbreak during the hajj. Health officials circulated among the sprawling tent camp at Mina where the pilgrims lived and gave the faithful cheek swabs for testing later. They also placed hand sanitizer dispensers on walls in the camps, near public bathrooms and at ritual sites, while pilgrims arriving at Saudi airports were scanned using a thermal camera and offered a free vaccine.

But authorities also are using the pilgrimage as a test case to build a database, watch for mutations and look for lessons on controlling the flu at other large gatherings like the 2010 soccer World Cup in South Africa.

Despite the relatively minor impact of the virus during the hajj, some experts warn it is likely spreading silently among pilgrims -- and the true extent of the push that hajj has given to the virus won't be known until later, after the faithful have returned to their home countries around the world.

Al-Rabeeah brushed aside such concerns Sunday, saying pilgrims have been in the country for almost a month, far longer than the weeklong incubation period.

"They've had enough time to show symptoms of swine flu, and that hasn't happened," he said.

But he also stressed Saudi authorities will continue to monitor pilgrims until they leave the country, and urged other countries monitor the pilgrims upon their return home.