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                                                                    EXHIBIT 23.1

               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

We consent to the incorporation by reference in the Registration Statements
(Form S-8) pertaining to the 1996 Equity Incentive Plan, Employee Stock Purchase
Plan, 1998 Non-Officer Stock Option Plan and 1999 Equity Incentive Plan of Cerus
Corporation of our report dated January 27, 2000, except for Note 9 as to which
the date is February 16, 2000, with respect to the financial statements of Cerus
Corporation included in its Annual Report (Form 10-K) for the year ended
December 31, 1999, filed with the Securities and Exchange Commission.


Walnut Creek, California
March 29, 2000