Scientists from the Netherlands, the U.K., and Qatar proved for the first time that dromedary camels can be infected with MERS-coronavirus. In a study co-funded by ANTIGONE and Emperie—two E.C. FP7 projects—researchers detected RNA of MERS-coronavirus in three dromedaries at a location where two people also were infected with the virus. The study was published this week in Lancet Infectious Diseases (article).
The samples were collected at a small farm in Qatar. Two people with a link to this farm, the owner and a worker, were infected with MERS-coronavirus. Within a week, the farm was investigated by the Supreme Council of Health and the Ministry of the Environment in Qatar, in cooperation with the World Health Organisation. They collected samples from the 14 dromedaries present on the farm, and submitted them to the Erasmus MC and the State Institute for Public Health and the Environment in the Netherlands.
Genetic analysis showed that the MERS-coronavirus was present in three of the dromedaries. The viral RNA from these dromedaries was very similar to that from the two patients, who had been examined by researchers from Public Health England. All the dromedaries had antibodies to MERS-coronavirus, indicating that they had been infected with the virus and had mounted an immune response.
According to the authors, this is “definite proof that dromedaries can be infected with MERS-coronavirus”. However, they caution that “we cannot conclude whether people were infected by the animals, or vice versa. A third possibility is that both people and dromedaries were infected by another, as yet unknown source. For this it is important to know the precise temporal sequence of the infections, both in people and in dromedaries. We do not have that information for this outbreak.”
They added that “a more extensive analysis of this outbreak is ongoing, including testing of multiple animals and of the environment. We are also trying to obtain the complete genome of the MERS-coronaviruses from people and animals. We cannot exclude that other common domestic animals, such as cattle, sheep, or goats, or other animal species are involved in the spread of this virus. In the meantime, we recommend that outbreaks are monitored in detail. Such monitoring should include exposure to animals and animal products and specific serological examination in order to determine risk factors for human infection, other than contact with an infected person.”