[Accepted Manuscript] Advanced HIV disease in Botswana following successful antiretroviral therapy rollout: Incidence of and temporal trends in cryptococcal meningitis.

Botswana has a well-developed antiretroviral therapy (ART) program which serves as a regional model. With wide ART availability, the burden of advanced HIV and associated opportunistic infections would be expected to decline. We performed a nationwide surveillance study to determine the national incidence of cryptococcal meningitis, and describe characteristics of cases 2000-2014 and temporal trends at two national referral hospitals. Cerebrospinal fluid data from all 37 laboratories performing meningitis diagnostics in Botswana were collected 2000-2014 to identify cases of cryptococcal meningitis. Basic demographic and laboratory data were recorded. Complete national data from 2013-2014 were used to calculate national incidence using UNAIDS population estimates. Temporal trends in cases were derived from national referral centers 2004-2014. 5296 episodes of cryptococcal meningitis were observed in 4702 individuals; 60.6% were male, and median age was 36 years. Overall 2013-2014 incidence was 17.8 cases/100,000 person-years (95%CI 16.6 - 19.2). In the HIV-infected population, incidence was 96.8 cases/100,000 person-years (95%CI 90.0 - 104.0); male predominance was seen across CD4 strata. At national referral hospitals, cases decreased 2007-2009 but stabilized 2010-2014. Despite excellent ART coverage in Botswana, there is still a substantial burden of advanced HIV, with 2013-2014 incidence of cryptococcal meningitis comparable to pre-ART era rates in South Africa. Our findings suggest a key population of individuals, often men, are developing advanced disease and associated opportunistic infections due to a failure to effectively engage in care, highlighting the need for differentiated care models.