<PAGE>
Filed Pursuant to Rule 497(e)
Registration File No.: 811-2978
33-44782
811-2932
811-3870
33-18983
SUPPLEMENT TO THE STATEMENTS OF ADDITIONAL INFORMATION OF
DEAN WITTER AMERICAN VALUE FUND DATED MAY 1, 1998
DEAN WITTER DIVERSIFIED INCOME TRUST DATED FEBRUARY 6, 1998
DEAN WITTER HIGH YIELD SECURITIES INC. DATED OCTOBER 31, 1997
DEAN WITTER U.S. GOVERNMENT SECURITIES TRUST DATED APRIL 17, 1998
DEAN WITTER UTILITIES FUND DATED APRIL 27, 1998
On June 22, 1998, the Dean Witter Funds were renamed the "Morgan Stanley
Dean Witter Funds." All references in the above-referenced Funds' current
Statements of Additional Information to the "Dean Witter Funds" or the "Dean
Witter Family of Funds" apply to the Morgan Stanley Dean Witter Funds or the
Morgan Stanley Dean Witter Family of Funds, and all references to a specific
Dean Witter Fund apply to the Fund's new name as a Morgan Stanley Dean Witter
Fund. For your convenience, a list of the above-referenced Funds with their new
names as Morgan Stanley Dean Witter Funds follows:
<TABLE>
<CAPTION>
OLD FUND NAME NEW FUND NAME
- ---------------------------------------- ------------------------------------------------------
<S> <C>
Dean Witter American Value Fund Morgan Stanley Dean Witter American Value Fund
Dean Witter Diversified Income Trust Morgan Stanley Dean Witter Diversified Income Trust
Dean Witter High Yield Securities Inc. Morgan Stanley Dean Witter High Yield Securities Inc.
Dean Witter U.S. Government Morgan Stanley Dean Witter U.S. Government
Securities Trust Securities Trust
Dean Witter Utilities Fund Morgan Stanley Dean Witter Utilities Fund
</TABLE>
The reference on the cover page of the Statement of Additional Information
of each of the above-referenced Funds (each a "Fund" and collectively the
"Funds") to the date of the Fund's Prospectus is hereby replaced by the
following:
<TABLE>
<S> <C>
Morgan Stanley Dean Witter American Value Fund May 1, 1998, revised August 21, 1998
Morgan Stanley Dean Witter Diversified Income Trust February 6, 1998, revised July 30, 1998
Morgan Stanley Dean Witter High Yield Securities Inc. October 31, 1997, revised July 30, 1998
Morgan Stanley Dean Witter U.S. Government April 17, 1998, revised August 14, 1998
Securities Trust
Morgan Stanley Dean Witter Utilities Fund April 27, 1998, revised August 19, 1998
</TABLE>
On March 24, 1998, Morgan Stanley, Dean Witter, Discover & Co., the parent
company of the Funds' Investment Manager, Transfer Agent and Distributor, was
renamed Morgan Stanley Dean Witter & Co. All references in the current
Statements of Additional Information to "Morgan Stanley, Dean Witter, Discover
& Co." or "MSDWD" apply to Morgan Stanley Dean Witter & Co.
On June 22, 1998, Dean Witter InterCapital Inc., the Funds' Investment
Manager, was renamed Morgan Stanley Dean Witter Advisors Inc. All references in
the current Statements of Additional Information to "Dean Witter InterCapital
Inc.," "InterCapital" or "the Investment Manager" apply to Morgan Stanley Dean
Witter Advisors Inc.
On March 24, 1998, Dean Witter Trust FSB, the Funds' Transfer Agent, was
renamed Morgan Stanley Dean Witter Trust FSB. All references in the current
Statements of Additional Information to "Dean Witter Trust FSB," "DWT" or "the
Transfer Agent" apply to Morgan Stanley Dean Witter Trust FSB.
On June 22, 1998, Dean Witter Distributors Inc., the Distributor of each
Fund, was renamed Morgan Stanley Dean Witter Distributors Inc. All references
in the current Statements of Additional Information to "Dean Witter
Distributors Inc.," "the Distributor" or "Distributors" apply to Morgan Stanley
Dean Witter Distributors Inc.
On June 22, 1998, Dean Witter Services Company Inc., a subsidiary of
Morgan Stanley Dean Witter Advisors Inc. that performs certain administrative
services for each Fund, was renamed Morgan Stanley Dean Witter Services Company
Inc. All references in the current Statements of Additional Information to
"Dean Witter Services Company Inc." or "DWSC" apply to Morgan Stanley Dean
Witter Services Company Inc.
August 21, 1998
