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Filed Pursuant to Rule 497(e)
Registration File No.: 33-48189
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER HEALTH SCIENCES TRUST
DATED SEPTEMBER 25, 1998
The last four sentences in the first paragraph under the subsection
entitled "Portfolio Management" in the section of the Prospectus entitled
"INVESTMENT OBJECTIVE AND POLICIES" are hereby replaced by the following:
The Fund's portfolio is managed within MSDW Advisors' Growth Group, which
manages 31 funds and fund portfolios, with approximately $12.4 billion in
assets as of November 30, 1998. Teresa McRoberts, Vice President of MSDW
Advisors, has been the primary portfolio manager of the Fund since December
31, 1998. Ms. McRoberts had assisted the former primary portfolio manager
of the Fund since September 1998. Ms. McRoberts has been a portfolio
manager at MSDW Advisors since July 1, 1998; prior thereto she was employed
at Fred Alger Management, Inc. (July 1994-May 1998) and J.P. Morgan & Co.
(July 1985-July 1994).
December 31, 1998
