We study the lifetime of a Bose gas at and around unitarity using a Feshbach resonance in lithium~7. At unitarity, we measure the temperature dependence of the three-body decay coefficient $L_{3}$. Our data follow a $L_3\,{=}\,\lambda_{3} / T^{2}$ law with $\lambda_{3}\,{=}\,2.5(3){\rm stat}(6){sys}\times10^{-20} (\muK)^2cm^6s^{-1}$ and are in good agreement with our analytical result based on the zero-range theory. Varying the scattering length $a$ at fixed temperature, we investigate the crossover between the finite-temperature unitary region and the previously studied regime where $|a|$ is smaller than the thermal wavelength. We find that $L_{3}$ is continuous across resonance, and over the whole $a\,{<}\,0$ range our data quantitatively agree with our calculation.
