  We determine the resummed 1-loop correction to a baryonic thermal screening
mass. The calculation is carried out in the framework of a dimensionally
reduced effective theory, where quarks are heavy fields due to their non-zero
Matsubara frequencies. The correction due to interactions is computed at
O($g^2_{ }$) in the coupling constant. In order to solve a 3-body Schr\"odinger
equation, we exploit a two-dimensional generalization of the hyperspherical
harmonics method. At electroweak scale temperatures, the NLO correction
represents a $\sim 4.6 \%$ increase of the free-theory value $3\pi T$ of the
screening mass.
