WHO: MERS intensifying, but doesn't constitute public health emergency

After meeting for the fifth time, the WHO International Health Regulations Emergency Committee expressed concern over the sharp rise in cases of Middle East respiratory syndrome, or MERS, but determined that the current situation has not met conditions for a public health emergency of international concern, according to Assistant Director-General Keiji Fukuda, MD, MPH.

“After a quite lengthy discussion in which they looked at all of the available facts and the different considerations and different perspectives, what they reached was a consensus that the situation had increased in seriousness, and their concern about the situation had also increased in terms of urgency,” Fukuda said during a teleconference. “However, when they looked at all of the information, they felt that the situation still fell short of calling it a public health emergency of international concern.”

Keiji Fukuda

The committee heard from health officials from 13 countries affected by the disease, each of whom reported on the current situation in their country. These included Egypt, Greece, Jordan, Kuwait, Lebanon, Malaysia, Oman, Philippines, Qatar, Saudi Arabia, the United Arab Emirates (UAE), the United States and Yemen.

The meeting lasted for approximately 5 hours, according to Fukuda. The committee acknowledged that the situation has worsened, with significant increases in MERS cases since March, largely in Saudi Arabia and the UAE. Most of these cases have occurred in hospitals.

“Ever since its emergence, hospital outbreaks have been a key feature of this particular virus,” Fukuda said.

The findings of an investigation by WHO in Saudi Arabia suggested that standard infection control practices in hospitals were suboptimal after conditions such as overcrowding in the ED led to secondary cases of infection.

There also has been an increase in cases in communities, although the reasons for this are unclear. According to Fukuda, one possibility is a “seasonal effect” of MERS. If so, it is possible that increased infections are occurring in an animal reservoir, which is causing infection in humans.

A second possibility for the rise in community cases is that surveillance of the disease is improving. In particular, health officials in Saudi Arabia are conducting more laboratory testing of MERS cases.

Fukuda said the “most troubling” possibility is an increase in human-to-human transmission. However, the committee determined that there is still no evidence of an increase in the transmissibility of the virus.

Investigations of contacts of MERS cases have not indicated an increase in secondary cases, and imported cases in travelers have not led to sustained transmission.

Five MERS viruses identified in recent cases — three from Saudi Arabia and two from travelers to the United States and Greece — have not shown any major changes in genetic sequences. Fukuda noted that even small genetic changes can lead to new properties in a virus, including increased transmissibility, but there is currently no evidence of genetic changes with the MERS coronavirus.

“The bottom line is that when the committee took all of this information and added it together, they didn’t see any convincing evidence of increased person-to-person transmissibility…” Fukuda said, “And so that was the major reason they said [MERS] doesn’t meet a public health emergency of international concern right now.”

Fukuda stressed four areas in need of improvement to limit the transmission of MERS worldwide. The first is to immediately strengthen prevention and control practices in all countries, but particularly in those countries heavily affected by the disease.

Secondly, more studies are needed to identify key risk factors for acquiring MERS and to clarify the role of animals in human infection.

“There are definitely gaps in information, and filling these gaps as soon as possible is another urgent need,” Fukuda said.

There also is a need for standardized guidance on how to manage individuals who come into contact with MERS cases.

Lastly, the committee stressed the need to raise awareness about MERS infection among people who attend mass gatherings.

The committee intends to meet again within the next few weeks to provide updates on MERS and make recommendations to the WHO Director General, although no specific date was announced.