Objective   To evaluate defending measures for SARSin the Xiaotangshan Hospital by analyzing immune state of medical staff who contacted with SARS patients.

  Methods   Flowcy to meter and hematology analyzer were used to detect the levels of leucocy tes, lymphocytes and its subsets, such as CD ₃ ⁺ Tcells including CD ₄ ⁺ and CD ₈ ⁺ cells, CD ₅₆ ⁺NK cells, CD ₁₉ ⁺B cells of peripheral blood from 92 medical staff in the hospital and blood specimens from 22 normal persons during SARS but non-contacted SARS in Beijing were collected and subjected to the same measurements.

  Results   The levels of leucocytes and the absolute value of lymphocytes, CD ₃ ⁺ Tcells, CD ₄ ⁺ T-cells, CD ₈ ⁺ T-cells, CD ₅₆ ⁺NK cells, CD ₁₉ ⁺B cells of medical staff in the Xiaotangshan Hospital and the normal persons during SARS were lower than nor mal people before SARS, expect that CD ₅₆ ⁺ NK cells was higher(P < 0.001, P < 0.05).But there was no difference between medical staff and normal persons during SA RS.

  Conclusion   Immune state of the medical staff was lower than before SARS because of the psychical irritation.The defending measures to SARScan effectively protect medical staff with irritability.