Modeling the impact of novel diagnostic tests on pediatric and extrapulmonary tuberculosis

BMC Infectious Diseases

Table 1 Parameters

Definition	HIV status	Value	Range	References
Non-TB death rate per year	all	0.022	0.02-0.025
TB mortality per year	HIV negative	0.15	0.1-0.22	[1, 19]
	HIV positive	0.50	0.4-0.7	[20]
Transmission events per infectious person-year in year 10*	all	8.95
Partial immunity afforded by previous infection	HIV negative	0.45	0.4-0.55	[21, 22]
	HIV positive	0	0-0.2
Proportion of TB infections progressing rapidly to active TB	HIV negative	0.14	0.05-0.14	[23]
	HIV positive	0.25	0.16-0.27
Endogenous reactivation rate per year	HIV negative	0.0005	0.08-1.4 x10⁻³	[24]
	HIV positive	0.05	0.03–0.05	[24]
Rate of self-cure in active TB per year	HIV negative	0.1	0.08-0.28	[25]
	HIV positive	0	0-0.2
Percent of patients without access to diagnostics	all	0.1	0.05-0.25	[26]
Sensitivity of current diagnostic standard for PTB	all	0.80	0.6-0.9	[18, 33]
Sensitivity of current diagnostic standard for EPTB	all	0.6	0.4-0.8
Sensitivity of novel test methods for PTB	all	0.95	0.75-0.98	[27–29]
Proportion of adults that develop EPTB or sputum scarce PTB in	HIV negative	0.18	0.15-0.25	[31, 32]
	HIV positive	0.35	0.3-0.7
Proportion of children that develop EPTB or sputum scarce PTB independent of HIV status (weighted average among different age groups)	all	0.85	0.6-0.9	[5]

Abbreviations: TB tuberculosis, NAAT nucleic-acid amplification test, EPTB extrapulmonary TB. *averaged over all patients with pulmonary TB (HIV-positive patients are estimated to be about half as infectious as HIV-negative patients).

ISSN: 1471-2334