Declining tuberculosis case notification rates with the scale-up of antiretroviral therapy in Zimbabwe

Setting: Zimbabwe has a human immunodeficiency virus (HIV) driven tuberculosis (TB) epidemic, with antiretroviral therapy (ART) scaled up in the public sector since 2004. Objective: To determine whether national ART scale-up was associated with annual national TB case notification rates (CNR), stratified by disease type and category, between 2000 and 2013. Design: This was a retrospective study using aggregate data from global reports. Results: The number of people living with HIV and retained on ART from 2004 to 2013 increased from 8400 to 665 299, with ART coverage increasing from <0.5% to 48%. TB CNRs, all types and categories, increased from 2000 to 2003, and declined thereafter from 2004 to 2013. The decreases in annual TB notifications between the highest rates (before 2004) and lowest rates (2013) were all forms of TB (56%), new TB (60%), previously treated TB (53%), new smear-positive pulmonary TB (PTB) (40%), new smear-negative/smear-unknown PTB (58%) and extra-pulmonary TB (58%). Conclusion: Significant declines in TB CNRs were observed during ART scale-up, especially for smear-negative PTB and extra-pulmonary TB. These encouraging national trends support the continued scale-up of ART for people living with HIV as a way of tackling the twin epidemics of HIV/acquired immune-deficiency syndrome and TB in Zimbabwe.