Chronic pulmonary cryptococcosis in a Rattus rattus from Rabaul, Papua New Guinea.

A wild Rattus rattus trapped in Rabaul, East New Britain Province, Papua New Guinea, was noted to have chronic, cystic pulmonary cryptococcosis. R. rattus is common in settlements in Papua New Guinea whereas pigeons, which have been suspected as a possible source of human cryptococcosis, rarely nest in villages in this country. If R. rattus was susceptible to chronic pulmonary cryptococcosis, because of its habit of nesting in roofs, it could serve as a possible vector of human cryptococcosis in Papua New Guinea and perhaps in other countries as well.