Charles J. Cashion
                                                     Chief Financial Officer
                                                     QUIDEL
                                                     (619) 552-7962

                                                     Christa Cerciello
                                                     Manager, Investor Relations
                                                     QUIDEL
                                                     (619) 646-8031


         QUIDEL CORPORATION COMPLETES ACQUISITION OF METRA BIOSYSTEMS

           Quidel expands product line into osteoporosis diagnostics

SAN DIEGO, August 11, 1999 -- Quidel Corporation (Nasdaq: QDEL) announced
today that it has completed its acquisition of Metra Biosystems, Inc. through
a merger of its wholly owned subsidiary, MBS Acquisition Corporation, into
Metra Biosystems. On July 13, 1999, Quidel acquired approximately 93% of the
outstanding Metra Biosystems shares through its $1.78 per share tender offer.
The remaining outstanding Metra Biosystems shares were converted into the
right to receive $1.78 share in cash effective August 5, 1999, after receiving
confirmation of the merger from the State of California on August 10, 1999.

"With the completion of the acquisition, Quidel is now poised to participate
in bone health assessment, particularly in the growing market of
osteoporosis, an area of diagnostics in which Metra Biosystems is a proven
leader," stated Donna McGill, vice president, women's health at Quidel.
"Metra's products provide a strategic opportunity to expand Quidel's presence
in women's health."

Quidel has assumed responsibility for Metra's distribution agreements and
strategic collaborations with major diagnostic and pharmaceutical companies,
including Abbott Laboratories, Beckman-Coulter, Inc., Bayer Corporation,
Diagnostic Products Corporation, Sumitomo Pharmaceuticals and others which
complement Quidel's corporate partnering strategy.

Quidel will continue to develop and commercialize Metra's portfolio of
diagnostic products for research and clinical use that provide physicians
with comprehensive clinical information regarding the metabolism of bone and
other connective tissues. With Metra's fourteen immunodiagnostic products,
including Pyrilinks -Registered Trademark- -D -- the Dpd bone resorption
test, and its new QUS-2 -TM- calcaneal (heel) ultrasonometer, Quidel believes
it is now the only U.S. company to offer both immunodiagnostic and scanning
technologies for the assessment and management of bone health.

In addition to the Metra products, Quidel Corporation discovers, develops,
manufactures and markets point-of-care rapid diagnostics for the detection of
human medical conditions and illnesses. These products provide simple,
accurate and cost-effective diagnoses for acute and chronic conditions in the
areas of women's health and infectious diseases. Quidel's products are sold
to professionals in the physician's office and clinical laboratories and to
consumers through organizations that provide private label, store brand
products.

This press release contains forward-looking statements regarding Quidel and
the combined companies of Quidel and Metra Biosystems and their future
activities within the meaning of the federal securities laws that involve
material risks and uncertainties. Many factors could affect future financial
results and performance, such that actual results and performance may differ
materially. Operating results may also be affected due to a number of
factors, including, without limitation, Quidel's ability to reduce costs
through consolidation of operations, seasonality, adverse changes in
competitive and economic conditions in domestic and international markets,
actions of major distributors, manufacturing and productions delays or
difficulties, adverse actions or delays in product reviews by the FDA, and
the lower acceptance of new products than anticipated. Please see the
discussion of these factors in the companies' annual reports, Form 10-K's and
Quidel's subsequent quarterly reports on Form 10-Q. Pyrilinks -Registered
Trademark- -D and QuS-2 -TM- are registered trademarks of Metra Biosystems,
Inc.