WHO experts probe Middle-Eastern respiratory syndrome coronavirus (MERS-CoV) in Jeddah, Saudi Arabia

2 May 2014

A team of experts from WHO started a two-day mission yesterday in Jeddah to assist national health authorities to investigate the recent increase in number of people infected by MERS-CoV.

WHO experts visiting intensive care unit at King Fahd General Hospital in Jeddah
WHO/T. Jasarevic

From mid-March 2014, 111 people have tested positive in the Jeddah area; the biggest single surge in the MERS-CoV outbreak since the new virus was detected in April 2012. Thirty-one persons have died.

As a large proportion of infections in Jeddah occurred in health-care facilities, the WHO team began with analyzing transmission patterns in the city’s main hospitals.

“We need to understand how people got infected in health-care settings, and in the community; we are looking into possible infection routes and whether the virus has changed its ability to more easily infect people,” says Dr Jaouad Mahjour, WHO Team Leader, “but we know that the systematic application of basic infection prevention and control measures in health facilities is key to limiting transmission and protecting health-care workers and other patients.”

Following the confirmation of the first cases, health facilities increased laboratory testing of patients, close contacts and health-care workers and strengthened protective measures. One third of the people tested positive in the recent spate of cases are health-care workers with mild or no symptoms.

“...but we know that the systematic application of WHO-recommended infection control measures In health facilities is key to limiting the transmission and protecting health-care workers and other patients.”

Dr Jaouad Mahjour

“Our priority is to stop the transmission inside the hospital by strengthening infection prevention and control activities,” says Dr Mohammed Al Ghamdi, an Infectious Disease Consultant at the King Fahd Hospital, the city’s main general hospital - where 78 people have tested positive so far. “WHO is helping us in getting answers on transmission routes not only in health facilities, but also in the community.”

Primary source of infection

Camels are increasingly being seen as the primary source of the MERS-CoV infecting humans, as recent studies showed that camels can harbour live virus. However, it is still unclear how exactly the virus is being transmitted to humans. Once infected, the person can pass the virus to other people, but no sustained chains of infection have been observed.

“Until we better understand how the virus transmits from camels or the environment to a human, we are likely to see more cases, and with travel, the virus is exportable,” said Dr. Mahjour. “Therefore, understanding this link is key to limiting the outbreak. There is an urgent need to conduct an in-depth epidemiological study of known cases to get this knowledge.”

Based on the current situation and available information, WHO encourages all Member States to continue their surveillance for severe acute respiratory infections (SARI) and to carefully review any unusual patterns.

Until further information is gathered, it is prudent for persons at high risk of severe disease due to MERS-CoV (including those with diabetes, chronic lung disease, pre-existing renal failure, or those who are immunocompromised) to take appropriate precautions when visiting farm and market environments where camels are present. These measures might include avoiding contact with camels, good hand hygiene, and avoiding drinking raw milk or eating food that may be contaminated with animal secretions or products unless they are properly washed, peeled, or cooked.

For the general public, when visiting a farm, live animal markets or a barn, general hygiene measures, such as regular hand washing before and after touching animals, avoiding contact with sick animals, and following food hygiene practices, should be adhered to.

WHO does not advise special screening at points of entry with regard to this event nor does it currently recommend the application of any travel or trade restrictions.