However, the intermediate host that allowed the virus to cross the species barrier to infect humans remains unknown, and the route of transmission is yet to be elucidated.
Hata hivyo, mbebaji wa kati aliyesaidia virusi hivi kuhamia kwa binadamu kutoka kwa kizuizi cha aina hiyo ya mnyama bado hajulikani na njia ya usambazaji wake bado haijapambanuliwa.