FLICKR, NIAIDLast week, Saudi Arabian officials announced the 105th Middle East respiratory syndrome (MERS)-related death in the country since the causative coronavirus (CoV) emerged in the country in September 2012. While at first the MERS-CoV was largely a mystery, scientists have since been working to scan its genome, decipher its transmissibility, identify potential vectors, and develop vaccines against it. This week, two independent teams have advanced scientists’ understanding of the coronavirus: one group cultured the MERS-CoV, while another identified human antibodies that bind it and could inform therapies.
In February, Columbia University’s Ian Lipkin and his colleagues showed that MERS-CoV was common in camels living near areas where most of the documented human infections had occurred. Now, Lipkin’s team has identified diverse MERS-CoV quasispecies from Saudi Arabian camels. The researchers’ work was published in mBio this week (April 29).
“There appears to be a wide range of different viruses present within camels,” Lipkin told the University of Minnesota Center for Infectious Disease Research and Policy’s CIDRAP News.
“The finding of infectious virus strengthens the argument that dromedary camels are reservoirs for MERS-CoV,” coauthor Thomas Briese, also of Columbia University, said in a statement. “The narrow range of MERS viruses in humans and a very broad range in camels may explain in part why the human disease is uncommon: because only a few genotypes are capable of cross species transmission.”
The details of such transmission, however, remain unknown. Marion Koopmans from the National Institute of Public Health and the Environment in The Netherlands told CIDRAP in an e-mail that while “the culturing is a confirmation of the PCR findings that already made it clear that camels can be infected with MERS-CoV,” how humans are infected is not yet known. While evidence suggests that human illness is “likely to involve camels or camel products,” she wrote, the causes are “still unclear.”
Meanwhile, writing in Science Translational Medicine this week (April 28), a team led by investigators at Tsinghua University in Beijing reported its isolation of two human neutralizing monoclonal antibodies that specifically recognize the receptor-binding domain (RBD) of the MERS-CoV viral envelope. The antibodies, MERS-4 and MERS-27, “could serve as promising candidates for prophylactic and therapeutic interventions against MERS-CoV infection,” Tsinghua’s Linqi Zhang and his colleagues wrote in their paper.
As Reuters reported, the World Health Organization (WHO) last week advised that people avoid contact with camels in order to slow the spread of MERS. According to The Wall Street Journal, Saudi Arabian officials are launching a public health campaign aimed at informing citizens about the dangers of MERS. Ian Mackay from the University of Queensland in Australian told the WSJ that “very rapid, transparent, and comprehensive communication is one of our best weapons to keep [people safe].”