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\item Prevalence from national prevalence surveys  \end{enumerate}  Using tuberculin survey results\cite{Styblo1985}  $$I^+ = \frac{\lambda \times 10^5}{2 \times 10} = 50.10^{-5} y^{-1}$$  First WHO systematic estimation exercise\cite{1600578}.  Global reassessment\cite{10517722}.  Using tuberculin survey results\cite{Styblo1985}  $$I^+ = \frac{\lambda \times 10^5}{2 \times 10} = 50.10^{-5} y^{-1}$$