Funding and Innovation in Diseases of Neglected Populations: The Paradox of Cryptococcal Meningitis.

It is estimated that fungal infections cause 1 million deaths annually, accounting for 50% of all AIDS-related deaths [1]. In this specific patient group, data from 2009 revealed that fungal meningitis is responsible for approximately 500,000 deaths each year [2]. The most common fungal pathogen infecting the brain is Cryptococcus neoformans, a yeastlike pathogen that is highly efficient in causing damage to immunosuppressed human hosts [3]. The fungus, which is widespread in the environment, primarily reaches the lung after inhalation of environmental cells and disseminates to the brain in the immunosuppressed host. Clinical studies in humans in combination with animal models of neurological cryptococcosis enabled the classification of the disease into different syndromes, including meningitis, encephalitis, meningoencephalitis, ventriculitis, increased intracranial pressure, and space-occupying lesions [3]. According to the Centers for Disease Control and Prevention (CDC) of the United States, cryptococcal meningitis is a global problem. Estimates by Park and colleagues indicated that approximately 957,900 cases (range, 371,700–1,544,000) of cryptococcal meningitis occur each year, resulting in 624,700 deaths (range, 125,000–1,124,900) by three months after infection [2]. Currently, estimates of global disease burden, including disability-adjusted life year (DALY), are not available, since cryptococcosis is not separately reported. Most cases are opportunistic infections that occur among people with HIV/AIDS. Although the widespread availability of antiretroviral therapy (ART) in developed countries has helped reduce cryptococcal infections in these areas, it is still a major problem in developing countries where access to healthcare is limited. Throughout much of sub-Saharan Africa, for example, Cryptococcus is now the most common cause of adult meningitis, which may kill as many people each year as tuberculosis [2]. The high fatality rate, especially in developing countries, stems from late diagnosis, access only to the least effective treatments, and from drug resistance when treated.