Research in context
Evidence before this study
Cryptococcus neoformans is the most common cause of meningitis among adults in sub-Saharan Africa, due to the burden of HIV infection. We searched PubMed using the terms “cryptococcal meningitis” and “burden” on May 31, 2022, with no restrictions on language or date. Two studies have estimated the global burden of cryptococcal infection. One of the studies was published in 2008 and estimated the global incidence of cryptococcosis as 957 900 cases per year (range 371 700–1 544 000). This estimate was based on published cohorts primarily from the era before antiretroviral therapy became available, and the wide ranges indicate the high level of uncertainty of these estimates. The study used just three incidence publications to derive estimates for sub-Saharan Africa. The other study was published in 2017, and estimated the global burden of cryptococcal meningitis as 223 100 cases per year. This estimate used 2014 data from UNAIDS, and emerging country-specific data on cryptococcal antigen (CrAg) prevalence. Since the last estimate, AIDS-related deaths have declined by 28%. Antiretroviral therapy coverage has increased to 27·5 million adults (up from 15 million in 2014) and integrase inhibitors are now first-line therapy in many large HIV programmes.
Added value of this study
This is an updated global estimate of the burden of cryptococcal infection, using data from 2020. The landscape of HIV infection has changed drastically since the last estimate of global burden in 2014. We provide an updated estimate of the global incidence of HIV-associated cryptococcal disease using published UNAIDS data on HIV incidence, antiretroviral therapy access, retention in care, and published CrAg prevalence data.
Implications of all the available evidence
The estimates of national, regional, and global burden of cryptococcal meningitis are key to guide prevention strategies and determine needs for diagnostic tests, antifungal medicines, and medical supplies, such as diagnostics, lumbar puncture needles, and manometers. We estimate that cryptococcal disease still accounts for 19% of AIDS-related deaths, similar to 2014 estimates. To end cryptococcal meningitis deaths by 2030, cryptococcal diagnostics, meningitis treatments, and implementation of preventive screening are critically needed.