The Middle East Respiratory Syndrome Coronavirus, (MERS-CoV) has been confirmed in 571 people worldwide and arrived in the United States for the first time this month, according to the World Health Organization (WHO).

Studies suggest the syndrome is a zoonotic disease originating in cattle, but routes of transmission are unclear and so far, the mysterious disease does not seem to easily spread between people, according to WHO.

The World Organization for Animal Health (OIE) this week issued an update on MERS-CoV and what is known about its transmission between and within species.

  • The majority of reported human cases are a result of human to human transmission, without easy spread between people. In some cases the origin of human infection is unexplained.
  • MERS-CoV and antibodies to MERS-CoV have also been detected in samples taken from camels. To date, MERS-CoV has only been isolated from camels and people.
  • Although recent studies suggest that camels may be a source of some human infections the exact relationship between MERS-CoV infections in humans and animals remains unclear.
  • Potential sources include other humans, camels, other wild and domestic animals, as well as the environment, food and water.
  • Published serological studies also suggest that antibodies to MERS-CoV have been detected at a relatively high prevalence in sampled populations of camels in some Middle East and African countries.
  • Although some camel infections with MERS-CoV have been associated with mild respiratory symptoms in the animals, current evidence does not indicate that MERS-CoV causes significant illness in camels.
  • According to published literature other species of animals, including sheep, goats, cows, water buffalo and wild birds, have tested negative for the presence of antibodies to MERS-CoV.

Read more from the OIE.