[ARTHUR ANDERSEN LLP LETTERHEAD]
Office of the Chief Accountant
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
April 22, 2002
Dear Sir/Madam:
We have read the first, second, third and fourth paragraphs of Item 4 included in the Form 8-K/A, dated April 22, 2002, of Quidel Corporation to be filed with the Securities and Exchange Commission and are in agreement with the statements contained therein.
Very truly yours,
/s/ Arthur Andersen LLP
cc: Paul E. Landers, Vice President and Chief Financial Officer, Quidel Corporation
