In the present study the presence of yeasts on the skin, and in the oral cavity and vagina of Alouatta palliata (mantled howler monkey), Ateles geoffroyi (black-handed spider monkey), Cebus capucinus (white-faced capuchin) and Saimiri oerstedii Reinhardt, 1872 (red-backed squirrel monkey) from several sites of Costa Rica was examined. These primates have been characterized with regard to their feeding patterns (Jones, 1983; Happel, 1986) and geographical distribution (Massey, 1987; Lippold, 1988, Rodríguez and Chinchilla, 1996). Also, the bacterial flora as well as the endo- and ectoparasites of Costa Rican primates have been reported (Troyo et al., 2002; Calderón-Arguedas et al., 2004; Gamboa-Coronado et al., 2004; Chinchilla et al., 2005; Chinchilla et al., 2006). The present project is unique in being the first to assess the yeast flora in these Neotropical primates. The yeast Candida is a saprophyte in natural products, but has been isolated from the mucosa and skin of humans and animals (Mariat and Droulet, 1996). Candida is considered an opportunistic microorganism that causes disease in hosts with a weakened immune system (Ostrosky-Zeichner, 2003). The most common clinical manifestations of candidiasis are cutaneous, mucocutaneous and invasive infections. In humans, Candida infections of the mouth and esophagus are frequently associated with AIDS (de Repentigny et al., 2004). Vulvo-vaginal candidiasis is a common cause of vaginal discharge, soreness, vulvar burning, dysuria and local pruritus. Candida may be either a commensal or a pathogen of the vagina, which indicates that changes in the host vaginal defense mechanisms or changes in the vaginal micro-environment are generally necessary for Candida to induce pathology or association with clinical symptoms (Sobel, 1997). On the other hand, invasive candidiasis is reported in individuals with prolonged neutropenia such as those receiving treatment for leukemia or solid tumors, or transplantation therapy (García-Ruiz et al., 2004).

The finding of yeast in an individual or in a group of healthy monkeys does not imply that this microorganism is part of the normal flora of the respective species. It is likely, however, that the isolation of Candida in a particular population of monkeys is indicative of colonization, as has been well established for other animals (Mariat and Droulet, 1996). The purpose of the present work was thus to examine the presence of yeasts in the mucosa and skin of Neotropical monkeys.