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We present JHK$_{s}$ observations of the metal-poor ([Fe/H] $<$ -1.40)Dwarf-irregular galaxies, Leo A and Sextans A obtained with the WIYNHigh-Resolution Infrared Camera at Kitt Peak. Their near-IR stellar populationsare characterized by using a combination of colour-magnitude diagrams and byidentifying long-period variable stars. We detected red giant and asymptoticgiant branch stars, consistent with membership of the galaxy's intermediate-agepopulations (2-8 Gyr old). Matching our data to broadband optical and mid-IRphotometry we determine luminosities, temperatures and dust-production rates(DPR) for each star. We identify 32 stars in Leo A and 101 stars in Sextans Awith a DPR $>10^{-11}$ $M_\odot \,{\rm yr}^{-1}$, confirming that metal-poorstars can form substantial amounts of dust. We also find tentative evidence foroxygen-rich dust formation at low metallicity, contradicting previous modelsthat suggest oxygen-rich dust production is inhibited in metal-poorenvironments. The total rates of dust injection into the interstellar medium ofLeo A and Sextans A are (8.2 $\pm$ 1.8) $\times 10^{-9}$ $M_\odot \,{\rmyr}^{-1}$ and (6.2 $\pm$ 0.2) $\times 10^{-7}$ $M_\odot \,{\rm yr}^{-1}$,respectively. The majority of this dust is produced by a few very dusty evolvedstars, and does not vary strongly with metallicity.

Near-Infrared Stellar Populations in the metal-poor, Dwarf irregular Galaxies Sextans A and Leo A