rarely affects healthy people and generally occurs in people who are already sick and unable to fight infection such as HIV/AIDS, cancer, organ transplant, long-term steroid use, old age, malnutrition or autoimmune disease. Mechanism The infection is thought to be acquired through breathing in the organism from the environment. However, the exact source of infection is not known. The infection is not spread person-to-person. In Thailand, talaromycosis is more common during the rainy season; rain may promote the proliferation of the fungus in the environment. Diagnosis There is no accurate fast serological test. Diagnosis relies on identifying Talaromyces marneffei in cultures from clinical specimens such as sputum, blood, skin scrapings, lymph node, and bone marrow, by which time the disease is in the late-stage. Fungi in blood are found in half of case. Non-specific laboratory findings may show evidence of the fungus invading tissue, such as low platelets due to bone marrow infiltration, and elevated transaminases due to liver involvement. Biopsies of skin lesions, lymph nodes, and bone marrow demonstrate the presence of organisms on histopathology. Intracellular and extracellular forms are oval and have a characteristic transverse septum. In culture, colonies are powdery green and produce red pigment; however, cultures are negative in a significant number of cases. Medical imaging may reveal shadows in the lungs. Differential diagnosis The disease can look similar to tuberculosis and histoplasmosis Treatment Talaromycosis may be prevented in people at high risk, using the antifungal medication itraconazole, and is treatable with amphotericin B followed by itraconazole or voriconazole. Outcomes With treatment, less than 25% of those affected die. Without treatment, more than 75% will die. Epidemiology The exact number of people in the world affected is not known. Once considered rare, its occurrence increased due to HIV/AIDS to become the third most common opportunistic infection (after extrapulmonary tuberculosis and cryptococcosis) in HIV-positive individuals within the endemic area of Southeast Asia. While incidence in those with HIV began to decrease due to antiretroviral treatment, the number of cases in those without HIV began to rise in some endemic areas since the mid-1990s, likely due to improved diagnosis and an increase in other conditions that reduce immunity. The disease has been found to be more common in young farmers. Men are affected more than women. History T. marneffei was first isolated from a bamboo rat in Vietnam in 1956. Three years later, it was described by Gabriel