Searching for a change: The need for increased support for public health and research on fungal diseases

Abstract

Fungal diseases have been continually neglected over the years despite their alarming impact on human health. Recent estimates [1] suggest a global annual occurrence of approximately 3,000,000 cases of chronic pulmonary aspergillosis, more than 200,000 cases of cryptococcal meningitis, 700,000 cases of invasive candidiasis, 500,000 cases of Pneumocystis jirovecii pneumonia, 250,000 cases of invasive aspergillosis, 100,000 cases of disseminated histoplasmosis, over 10,000,000 cases of fungal asthma, and 1,000,000 cases of fungal keratitis. It is estimated that fungal infections kill more than 1.5 million people every year [2]. Morbidity due to fungal infections is also significant. Chromoblastomycosis and eumycetoma, for instance, cause debilitating diseases affecting subcutaneous tissues, skin, and underlying bones [3,4]. Importantly, the epidemiology of fungal diseases is dynamic and hard to predict. Recently, the multidrug-resistant pathogen Candida auris has emerged as a serious threat to human health, with some infections resistant to all main classes of antifungal medications [5]. Known diseases also raise new concerns. The city of Rio de Janeiro, Brazil, currently faces the largest epidemic of sporotrichosis in history [6]. Paracoccidioidomycosis is still one of the most important systemic mycoses in Latin America and the leading fungal cause of mortality in non-immunosuppressed individuals in Brazil [3,7]. Mortality and morbidity due to fungal diseases mostly affect individuals living under socioeconomic restrictions [8,9]. Reliable and cost-effective diagnostic tools are available for a very limited number of mycoses, and therapeutic options are restricted to a few classes of poorly effective, toxic, and expensive pharmaceutical agents [10]. There are no licensed antifungal vaccines [12]. The last antifungals approved for clinical use were the echinocandins in 2002 [11]. According to the Global Fund for Fungal Infections (GAFFI), several key antifungals also are not available or not even registered in multiple regions where fungal diseases are most lethal [2]. These serious gaps in diagnostic, therapeutic, and preventive tools for fungal infections are a dangerous combination that results in high costs and low efficacy of clinical approaches [13]. To minimize the number of deaths caused by fungal diseases, novel therapeutic, diagnostic, and preventive tools must be developed, and the diagnostic tests and antifungal agents that are available must be rationally deployed.