Abstract:
Old World alphaviruses were identified in 52 of 623 horses
with febrile or neurologic disease in South Africa. Five of
8 Sindbis virus infections were mild; 2 of 3 fatal cases involved
co-infections. Of 44 Middelburg virus infections, 28
caused neurologic disease; 12 were fatal. Middelburg virus
likely has zoonotic potential.
