The UN Food and Agriculture Organisation has called for increased scrutiny in order to establish whether animal contact has played a part in the development of a novel disease sweeping the Middle East.

FAO said, "Understanding the potential role of animals in the emergence and spread of Middle Eastern Respiratory Syndrome (MERS) requires further investigation, analysis and study." Currently, not enough evidence is available to identify the specific source, whether animal or otherwise, of the coronavirus that is causing MERS in humans.

Coronaviruses are a family of viruses that affect primarily birds and mammals. Some strains cause mild disease, while a limited number are more harmful (included amongst these more serious strains is the virus behind the SARS outbreak in 2002). Like SARS, The MERS coronavirus has been shown to cause acute respiratory illness in humans, it was first discovered last year but has not yet been shown to cause disease in animals.

Commenting on Friday, FAO's Chief Veterinary Officer Juan Lubroth said, "It is not yet clear how people are becoming infected, or where the virus might come from. We do not have enough information to identify with certainty the virus's origin. Confirming the source and mechanisms of transmission and spread are key to developing ways to reduce the risks posed by this virus to humans or other countries."

However, also on Friday, a study led by the National Institute for Public Health and the Environment of the Netherlands, published in The Lancet Infectious Diseases Journal, offered further insights into the disease.Researchers took blood samples from a number of livestock animals, including sheep, goats cattle and camels in a number of different countries, in a bid to detect antibodies indicative of the virus' presence.

The study found that the MERS coronavirus, or one like it, has been circulating in certain animals. Researchers detected evidence of the virus in camel blood samples. The samples were taken in areas where human cases have not been reported. In some cases, the tested camels had been isolated from other camels for many years.

These antibody findings indicate that the MERS virus, or a similar coronavirus, occurs in some camels and potentially other species. However, the only way to know with any certainty if the virus affecting humans is the same as the virus possibly affecting camels (or any other animal) is to isolate the virus in different species and compare them genetically.

To date the MERS coronavirus has only been isolated in humans. FAO called for an acceleration of investigation and research in animal species to shed light on potential animal sources. The Rome-based food and farming group said breakthroughs in understanding would likely translate into more effective disease control measures.

The SARS outbreak between 2002-2003, which caused widespread panic and spread from China, where the disease was first discovered, to the United States, Canada and Vietnam, has since been linked to certain subspecies of civet. Testing showed the disease was also present in a number of other animals. 

FAO said on Friday that its officials remain in close communication with national authorities in countries affected by MERS as well as the World Health Organization (WHO) and the World Organisation for Animal Health (OIE).