Scientists studied the sickness of a 44-year old man who was the owner of camels in Saudi Arabia. The man died this past November from the Middle East Respiratory Syndrome, also known as MERS.
After repeated tests, the researchers could show that the man and one particular camel were infected by the same virus. The camel was infected first and the man was sickened after he put medicine on the runny nose of the animal.
MERS had been previously detected in camels. Officials believe the virus had spread previously to people from camels in some of the MERS cases. However, clear proof that happened had been lacking.
Dr. William Schaffner from the University of Vanderbilt is an expert in infectious disease. Schaffner said that earlier research had different parts of the puzzle making this story quite likely, but in this particular episode, all the parts came together.
The New England Journal of Medicine published the study online Wednesday.
The virus is an illness that attacks the respiratory system that starts with a cough and fever that is flu-like, but can cause pneumonia, shortness of breath and even death.
Since MERS first appeared over two years ago, close to 800 cases have been confirmed in health agencies and 300 deaths.
The majority of cases have originated in Saudi Arabia and its neighboring countries. The case outside of that region, including two confirmed in the U.S., have mostly been in people who had previously traveled to the Middle East.
What is not known is how frequent the spread from camel to human occurs and if environmental sources or other animals are transmitting the deadly virus.
Workers in healthcare and members of families have been infected after having close contact with patients that have MERS.
The report details how the man owned as many as nine camels and maintained them inside a barn in the southwest region Saudi Arabia.
Last October four of the camels fell ill and a week later the man developed symptoms that were flu-like.
He was then hospitalized in the city of Jeddah and died two weeks later while the camel survived.