health standpoint, this positive view may not always be valid,
since free-living birds carry a diversity of microorganisms that are
pathogenic to humans[2]. Pigeon droppings have been reported
as the major environmental source of Cryptococcus neoformans
(C. neoformans) as well as many other pathogens in several
countries[3-5]. C. neoformans is an encapsulated yeast-like fungus
that causes cryptococcosis and its inhalation from environmental
sources may cause pulmonary and neurological diseases in
susceptible humans[6]. The incidence of cryptococcal infection has
recently increased around the world as a result of a large increase in
patients suffering from AIDS, population aging, and the expanded
use of immunosuppressive drugs for cancer treatment and organ
transplantation[6-8]. Since there are no available studies on the
environmental distribution of C. neoformans in Saudi Arabia,
there is an urgent need to investigate this point. The present study