The route of infection is usually arised as a hematogenous spread from unevident primary focus like respiratory tract, geno-urinary tract, gastrointestinal tract, and skin infection etc.

• 这些细菌可经由不知部位的感染后经血行性传来，例如上呼吸道，泌尿道，消化道及皮肤的感染所致。