  How dissipation affects transport is an important theme in quantum science.
Here we theoretically investigate an impact of a single-particle loss in
mesoscopic transport, which has been an issue in experiments of ultracold
atomic gases. By explicitly analyzing quantum point contact and quantum dot
systems, we obtain a cumulant generating function on the particle current whose
formal expression turns out to be common to two systems. In terms of this
generating function, behaviors of average current, particle loss rate, and
noises in presences of losses introduced in conduction channels are exemplified
for free fermions. It is shown that the current noise contains the component
proportional to the particle loss rate, which may be measurable in experiments.
