The description of the Infected debuff reads : "On death, spread all statuses to nearby enemies within Xm". However, SLOW is not spread.
Experimenting with status effect duration (Timekeeper's jewel ring, Affliction trait), damage increases (Ritualist's Wrath perk, Ahanae's Ring) as well as the description on the fetid wounds mutator (3% increased crit chance per status effect on target, up to 15%) has lead me to believe SLOW is meant to be a status effect.
If this interaction is intended (spreading SLOW sounds too strong), I think the description of the Infected debuff could be fixed by specifying "damaging statuses" are spread.
Tested with Misfortune Melee Mutator, Stasis Beam mod and Scrap Shot mod on Losomn Nurses and multiple Labyrinth enemies. Can be further tested/duplicated by killing any slowed enemy next to a non-slowed enemy with ritualist equipped as primary archetype.