Rats are infecting humans with hepatitis, and nobody knows how https://www.cnn.com/2020/05/08/health/hong-kong-rat-hepatitis-intl-hnk-scn/index.html
As always, I am pretty sure that when they eventually identify the means of transmission, it will involve chop sticks somewhere along the line. I am joking. OR NOT.
Considering sex with a rat is highly unlikely I'm going with chopsticks. Rice and rat sounds like the probable dish, along with a side of bat wings.
Ticks perhaps also, they can transmit Hep C, could be rat ticks. I have seen sick rats try and get into cool air conditioned places a few times.