GENEVA (AFP) - A surge in cases of the deadly Middle East respiratory syndrome (Mers) virus has receded, but countries must maintain vigilance for the Muslim pilgrimages to Saudi Arabia, the country worst hit by the disease, the World Health Organisation (WHO) said on Tuesday.
"The upsurge in cases that began in April has now decreased and there is no evidence of sustained human-to-human transmission in communities," it said in a statement.
However, "the situation continues to be of concern, especially given the anticipated increase in travel to Saudi Arabia related to Umrah, Ramadan and the Hajj", the United Nations health agency said.
The communique was issued after a teleconference of health officials from seven countries where there have been cases of Mers. They were Algeria, Iran, Jordan, the Netherlands, Saudi Arabia, the United Arab Emirates and the United States.
Mers has killed 284 people in Saudi Arabia since it first emerged in April 2012, and hundreds more have been infected. Twenty-two countries have reported cases.
It is considered a deadlier but less transmissible cousin of the severe acute respiratory syndrome (Sars) virus that appeared in Asia in 2003 and killed hundreds of people, mostly in China.
Close contact with camels has been fingered as the likely source of Mers in humans, according to a preliminary investigation by the WHO.
Millions of pilgrims visit holy sites in western Saudi Arabia for the annual haj, the major Muslim pilgrimage that this year will take place in October, and for the umrah, which is performed throughout the year.
Last year, five million pilgrims visited the kingdom for umrah and the haj.
The WHO said its Emergency Committee on Mers unanimously concluded that the conditions needed to declare a worldwide alert, dubbed a "Public Health Emergency of International Concern", "have not yet been met."
But it urged vulnerable countries, particularly in Africa, to beef up monitoring, raise public awareness and implement basic infection procedures.
Professor David Heymann, a professor of epidemiology at the London School of Hygiene and Tropical Medicine, said it was vital to put in place measures to protect health workers and hospital patients from infection by someone with the Mers virus.
"Health workers are at great risk from emerging infections and can then unintentionally infect other patients and contacts including family members if hospital infection control measures are not in place or not being respected," Prof Heymann said in comments reported by the Science Media Centre in London.