The large inclusion bodies are composed of finely granular material or thin helicoid filaments and seen to be surrounded by a disarranged collection of glycogen vacuoles or mitochondria.

• 电镜观察还原体呈多孔状结构，由致密的细丝、颗粒组成，不仅分布在核附近、胞浆内，还见于胞核内。