A retired serviceman who lovingly tended his drippy-nosed camels was almost certainly infected with MERS by one of them, Saudi researchers say in a report that makes the first direct link between camels and the mysterious virus.
Genetic tests show the man, who died last November, was infected by a virus identical to the one affecting his small herd of camels.
Experts have known that camels are a source of MERS, but until now there had not been a definitive link showing direct infection.
“These data suggest that this fatal case of human MERS infection was transmitted through close contact with an infected camel," Dr. Tariq Madani of King Abdulaziz University in Jeddah and colleagues reported.
“Nasal swabs collected from the patient and from one of his nine camels were positive for MERS,” they wrote in their report, published in the New England Journal of Medicine.
“The full genome sequences of the two isolates were identical,” they added. Further tests showed the virus had been circulating in the camels before the man got infected.
The 44-year-old retired soldier had been healthy until he developed a fever, runny nose and a cough. He was admitted to the hospital in November. He had a small herd of nine camels, and friends said four of them had runny noses and that the sick owner had spent up to three hours a day daubing herbal remedies into their nostrils.
In October of last year, he got sick himself.
“He did not clean the stables or milk the animals, but he routinely consumed raw, unpasteurized camel milk from the herd,” former deputy Saudi health minister Dr. Ziad Memish and colleagues said in a separate report published in the June issue of the journal Emerging Infectious Diseases.
It’s still not entirely clear how most people are becoming infected with MERS. Most cases have no evidence of direct contact with animals, and many of them have been infected by other people, mostly in hospitals and clinics.
Memish said juvenile camels may be prone to infection. Evidence suggests adult camels clear the virus eventually. If it's young camels, Memish reported, that may help explain why so many new cases have appeared in the spring: Camels usually give birth in the winter, and the young ones would be getting more active by spring.
Some evidence suggests bats may sometimes get infected, also, but how humans might get infected via bats is also not clear.
Middle East Respiratory Syndrome (MERS) first arose in 2012. It’s spread to about 20 countries but all cases have been linked to the Arabian peninsula.
Two health care workers who had been working in Saudi hospitals carried the virus to the U.S. in recent weeks, but both have recovered and have not appeared to have infected anyone else. The Centers for Disease Control and Prevention feared one man was infected by one of the travelers, but later said new tests showed he had not been.
Saudi officials said Tuesday they had found 113 more cases of MERS infection in old medical records — and more than 90 extra deaths. At almost the same time officials also announced they had fired Memish, who had been heading the kingdom’s MERS efforts.
U.S. and World Health Organization health experts have been trying to pressure Saudi Arabia to share more information about MERS, and to accept outside help in its efforts to fight the virus.
The new numbers would bring the total Saudi toll from MERS to 282 deaths out of 688 cases, making for a 40 percent fatality rate. Not all the cases have been confirmed by WHO, which puts the global count at 681 cases and 204 deaths.
WHO and other experts agree that studies are desperately needed on how much of the population is infected with MERS, especially in Saudi Arabia, where the vast majority of cases have been. MERS is a coronavirus, in the same family of viruses as many common cold viruses, and it’s possible that people can be infected and get symptoms no worse than a sniffle.
“It is not always possible to identify patients with MERS early because some have mild or unusual symptoms,” WHO says in a statement. “For this reason, it is important that health-care workers apply standard precautions consistently with all patients — regardless of their diagnosis — in all work practices all the time.”
And WHO warns about contact with animals, too. “For the general public, when visiting a farm 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,” the organization advises.