The deceased were older than 50 and chronically ill, which means they were in the group of people at a higher risk of contracting a more severe form of the virus.
Of those infected, 43 have or had symptoms of meningitis, encephalitis or meningoencephalitis.
Forty-eight of those infected are from Belgrade.
West Nile fever is widespread in Africa and other parts of the world. Transmission to humans comes via mosquitoes from infected birds.