SUMMARY The levels of soluble CD4 (sCD4), sCD8 and β2‐microglobulin (β2‐M) were measured in sera from patients with visceral leishmaniasis during the course of infection. Levels of sCD4. sCD8 and β2‐M were raised significantly above levels In normal sera and returned to the normal range after recovery. The decrease in the levels of CDS was related to a reduction of anaemia, leukopenia and thrombocytopenia. In contrast, sCD4 levels fluctuated during the period of infection. β2‐M returned within normal range more rapidly than sCD8 secretion. Our results suggest that T cells are activated during infection, and that it is also possible that the raised levels of these soluble molecules play a role in the impairment of protective immunity.