Three different mouse strains (Mus musculus) that developed
disease upon infection with mouse-adapted SARS-CoV have been
evaluated as MERS-CoV infection models: immunocompetent
BALB/c mice, 129S6/SvEv and innate immune-deficient
129/STAT1/ mice. Eight-week-old mice of these strains were
intranasally (IN) inoculated with PBS, 120 or 1200 TCID50 of
MERS-CoV strain HCoV-EMC/2012 and euthanized on 2, 4
(BALB/c) or 9 (129S6/SvEv and 129/STAT1/) dpi. No significant
weight loss was observed and no infectious virus could be detected
in the lungs of any mouse strain. Genomic MERS-CoV RNA was
detected, but no viral messenger RNA. Only minor pathological
lesions or signs of an inflammatory response were observed in
the lungs. Seropositivity in these mice was not tested. Together,