Overview of Fungi Classified as Risk Group 3 by the Japanese Society for Medical Mycology.

Fungi are categorized into Risk or Hazard Groups, depending on their potential to harm humans, with groupings ranging from 1 (least risky) to 4 (most risky). Similarly, Biosafety or Containment Levels ranging from 1 to 4 denote the level of control over microorganisms in laboratories. This review focuses on fungi categorized as Risk Group 3 by the Biosafety Committee of the Japanese Society for Medical Mycology. One such fungus is Blastomyces dermatitidis, which is primarily found in North America and causes blastomycosis, a condition that can result in a pulmonary or disseminated disease. It is classified as Risk Group 3, as substantiated by 11 laboratory-acquired infections and two fatalities. Cladophialophora bantiana, commonly found in Asia, causes brain abscesses and is also classified as Risk Group 3 due to a high mortality rate of 65.2%. Coccidioides immitis/posadasii, found in the Americas, can cause severe respiratory conditions with the potential for dissemination. Their Risk Group 3 classification is substantiated by a history of laboratory-acquired infections. Histoplasma capsulatum, which is found globally, causes a range of infections, from asymptomatic to fatal. Its classification as Risk Group 3 is substantiated by 81 laboratory-acquired infections and one fatality. Rhinocladiella mackenziei, which primarily affects the nervous system, has a mortality rate of 92.5% and is also classified as Risk Group 3. These fungi necessitate strict containment measures in laboratories owing to their high mortality rates or reported cases of laboratory-acquired infections and fatalities, emphasizing the critical need for heightened awareness and stringent safety protocols.