The victims of the virus were a 17-year-old Nigerian female and a Sudanese man, an Indian man and a Moroccan woman who were all 75 years old.

"These cases were discovered too late," said Dr. Khaled Al-Marghalani, the ministry spokesman. "Some were old, and the others had pre-existing chronic conditions."

Al-Marghalani said the Sudanese man initially went to a doctor who treated him, but not for H1N1.

"So when his doctor sent him to hospital to be treated for H1N1, it was too late," he said.

The annual pilgrimage to Mecca, Saudi Arabia, is required of Muslims at least once in their lives, and millions of people around the globe make the trek to attend. This year, the hajj begins Wednesday, and many pilgrims have been arriving days and weeks ahead of the event, which coincides with flu season.

CNN