Problems with the WHO TB model

Abstract

WHO tuberculosis researchers recently published a mathematical model to predict TB incidence decline with fulfillment of Sustainable Development Goal (SDG) subtargets [1]. This model omitted the subtargets of land rights and basic services and of reduction in deaths from climatic disaster, likely highly influential factors, and retained only social insurance and reduction of extreme poverty as independent variables. The model predicted that fulfillment of these two subtargets will result in very large declines in TB incidence.This paper critiques the WHO model, reviews historic documents in TB social epidemiology, and examines dynamics of institutional effectiveness and efficiency in endemic disease control under conditions of systemic uncertainty associated with imbalances in population-level power relations, leading to exploding variance. These documents, and our own modeling exercise, indicate that the WHO model omits important determinations of TB incidence: war, civil conflict, and major upheaval such as rural and urban mass evictions; gross imbalance of power; accumulation of wealth into the hands of a tiny part of the global population; unequal female/male literacy and general low literacy level.Simple models should not be used for public policy, especially not-yet-validated models. The WHO model substitutes money for anti-TB medicines and leaves the underlying long-term causes of high TB incidence intact. Short-term reductions in TB incidence may be followed by increases as intervention effectiveness and efficiency ebb.