[The temporary immunodepression observed in trichinosis: is it related to acceptance of this parasite by its host?]

Swiss mice given 200 Trichinella larvae followed by a further 200 larvae 21 days later were found to be immune and did not show any immunodepression to sheep red blood cells (SRBC). When the challenge dose was given 56 days after the first infection, the pattern of infection was unaffected and an immunodepression to SRBC was observed. Therefore, the immunodepression in trichinellosis might be related to the migrating phase only.