Incidents during the Hajj
City officials are required to control large crowds and provide food, shelter, sanitation, and emergency services for millions.
Pilgrims ritualistically throw pebbles at three walls (formerly pillars before 2004) which represent the three places where the Hadiths describes how the devil tempted Abraham.
Some notable incidents include: Mingling of visitors from many countries, some of which have poor health care systems still plagued by preventable infectious diseases, can lead to the spread of epidemics.
If an outbreak were to occur on the road to Mecca or Medina, pilgrims could exacerbate the problem when they returned home and passed their infection on to others.
One such disease, which prompted a response from the Saudi government, is meningitis as it became a primary concern after an international outbreak following the Hajj in 1987.
Due to post-Hajj outbreaks globally of certain types of meningitis in previous years, it is now a visa requirement to be immunised with the ACW135Y vaccine before arrival.
Every year, the Saudi government publishes a list of required vaccines for pilgrims, which for 2010 also included yellow fever, polio, and meningitis.
[26][27] As of 9 September 2013[update], the Saudi government asked "elderly and chronically ill Muslims to avoid the Hajj this year" and restricted the numbers of people allowed into the country due to Middle East respiratory syndrome coronavirus (MERS-CoV).
In 1905 the El Tor strain of cholera was discovered in six pilgrims returning from Hajj at the El-Tor quarantine camp in Egypt.
Much of the pilgrimage and its rituals are performed outdoors, on foot, and by elderly people, making pilgrims more susceptible to the intense heat present in Mecca during the summer.
Outdoor rituals include standing on the plain of Mount Arafat from sunrise to sunset and walking for several hours in the outskirts of Mecca on other days.
The average daily wet-bulb temperatures during Hajj between 1979 and 2019 exceeded the US National Weather Service danger threshold of 24.6 °C (76.3 °F) on 38 days, nearly half of which took place in 2015–2019.
[37] Attempts to mitigate the heat include portable water stations and misting systems, as well as expansive air conditioning in the floor of the Great Mosque of Mecca and in surrounding tents.
The Saudi government insists that any such mass gatherings are inherently dangerous and difficult to handle, and that they have taken a number of steps to prevent the problems.
Additional accessways, footbridges, and emergency exits were built, and the three cylindrical pillars were replaced with concrete walls to enable more pilgrims simultaneous access to them without the jostling and fighting for position of recent years.
