Infant mice, but not adult immunocompetent or scid mice, are susceptible to experimental infection. Natural infection of mice has not been reported. SDAV infections follow patterns similar to those of MHV, another coronavirus. Suckling rats develop transient conjunctivitis. Weanlings and adults are asymptomatic.
Epizootic infection occurs when the agent is introduced to a fully susceptible population.
Clinical signs are again transient, may vary in severity, and include cervical edema, sneezing, photophobia, conjunctivitis, nasal and ocular discharge, porphyrin staining, and corneal ulceration and keratoconus. Multiple strains of SDAV exist, and tissue tropisms differ somewhat among strains. SDAV has a tissue tropism for tubuloalveolar glands of the serous or mixed serous-mucous types. Secondary damage may occur to structures of the eye. Cervical lymph nodes and the thymus may also be mildly necrotic.