To develop effective therapeutics and vaccines against MERS-CoV, scientists must first understand how the virus survives, infects, and causes disease in people. This knowledge is gained by first studying the virus in tissue culture and then developing animal models that mimic human disease. After studies showed that MERS-CoV does not cause disease in standard mice or hamsters, scientists at NIAID Rocky Mountain Laboratories (RML) took the unusual step of moving directly to developing a large-animal model because of the public health implications posed by MERS.
Their model of MERS-CoV infection in rhesus macaques shows that clinical signs of disease appear within 24 hours of infection, and the virus causes disease deep within the lungs, leading to pneumonia. The RML team is using the rhesus model and another developed in marmosets to study how MERS-CoV causes disease and to evaluate potential vaccines and treatments. NIAID-funded researchers have established, in a 2014 study and another in 2015, several small animal models of infection in mice. Researchers at NIAID and elsewhere continue to try to develop a small-animal study model in other rodents and rabbits. Such models may be simpler to use and less expensive than macaques, and can be used to evaluate new treatments for MERS-CoV.
NIAID-funded investigators also are working to express, screen, catalog, and biochemically characterize novel MERS-CoV genes to identify new immune pathways related to viral replication and the host defense against MERS-CoV.