But in its fourth meeting on Middle East respiratory syndrome, the so-called emergency committee reiterated earlier calls for improved surveillance for the virus, bolstered laboratory capacity in vulnerable countries and timely sharing of information on cases.
The committee also stressed the need for a range of scientific studies, many of which scientists involved in MERS research wish had already been conducted.
They pushed for an international case control study, a kind of research project that is typically done in the earliest stages of an outbreak. People who have contracted an illness — in this case MERS — are compared to similar people who have not to help investigators zero in on how people are becoming infected.
The committee also called for studies that look for MERS antibodies in the blood of a range of people in affected countries in an attempt to see how many infections have gone unnoticed. A recent mathematical study estimated that for every case of MERS spotted there may be between five and 10 cases undetected because surveillance systems are mainly designed to detect severely ill cases.
Many MERS researchers and the WHO itself have been pleading for months to have the most badly hit country, the Kingdom of Saudi Arabia, conduct these types of studies. It remains unclear whether the kingdom has done or is doing this work, and if it has not, why not.
"Obviously it's never too late to do these studies... but again it begs the question why they weren't done six or seven months ago," said Michael Osterholm, an infectious diseases specialist who has been following the MERS outbreak closely.
"I've had so many discussions ... with colleagues around the world and the one thing we keep coming back to over and over again is the issue of: Why is the kingdom not doing this work?"
Saudi Arabia's deputy minister of health, Dr. Ziad Memish, is a member of the emergency committee and he took part in Wednesday meetings. Also on the conference call were health representatives from several other countries which have recently reported MERS cases: Kuwait, Oman, Qatar and Spain.
Spain reported the only known cases of infection in people who travelled to Saudi Arabia to take part in the Hajj, the international pilgrimage that draws several million Muslims to Mecca each year. Two residents of Spain, both women, became sick while in Saudi Arabia, but travelled home before seeking care.
They are currently still listed as probable MERS cases while additional testing is being done. To date there have been 163 confirmed MERS infections, 72 of which have been fatal.
The emergency committee also stressed the need for greater emphasis on infection control in hospitals in affected countries.
A study published in early November reported that at least 60 secondary cases of MERS — where the virus was transmitted from an infected person to a contact — have occurred in health-care settings. Those secondary cases have included health-care workers, other patients and visitors.
Dr. Theresa Tam, head of the Public Health Agency of Canada's health security infrastructure branch, is vice-chair of the emergency committee.