REPORT OF INDEPENDENT REGISTERED PUBLIC
ACCOUNTING FIRM

To the Shareholders and Board of Trustees of
Morgan Stanley Health Sciences Trust:

In planning and performing our audit of the financial statements of
Morgan Stanley Health Sciences Trust (the Fund) as of and for the
year ended July 31, 2005, in accordance with the standards of the
Public Company Accounting Oversight Board (United States), we
considered its internal control over financial reporting, including
control activities for safeguarding securities, as a basis for designing
our auditing procedures for the purpose of expressing our opinion on
the financial statements and to comply with the requirements of Form
N-SAR, but not for the purpose of expressing an opinion on the
effectiveness of the Fund’s internal control over financial reporting.
Accordingly, we express no such opinion.

The management of the Fund is responsible for establishing and
maintaining effective internal control over financial reporting.  In
fulfilling this responsibility, estimates and judgments by management
are required to assess the expected benefits and related costs of
controls.  A company’s internal control over financial reporting is a
process designed to provide reasonable assurance regarding the
reliability of financial reporting and the preparation of financial
statements for external purposes in accordance with generally accepted
accounting principles.  Such internal control includes policies and
procedures that provide reasonable assurance regarding prevention or
timely detection of unauthorized acquisition, use or disposition of a
company’s assets that could have a material effect on the financial
statements.

Because of its inherent limitations, internal control over financial
reporting may not prevent or detect misstatements. Also, projections of
any evaluation of effectiveness to future periods are subject to the risk
that controls may become inadequate because of changes in conditions,
or that the degree of compliance with the policies or procedures may
deteriorate.

A control deficiency exists when the design or operation of a control
does not allow management or employees, in the normal course of
performing their assigned functions, to prevent or detect misstatements
on a timely basis. A significant deficiency is a control deficiency, or
combination of control deficiencies, that adversely affects the
company’s ability to initiate, authorize, record, process or report
financial data reliably in accordance with generally accepted
accounting principles such that there is more than a remote likelihood
that a misstatement of the company’s annual or interim financial
statements that is more than inconsequential will not be prevented or
detected. A material weakness is a significant deficiency, or
combination of significant deficiencies, that results in more than a
remote likelihood that a material misstatement of the annual or interim
financial statements will not be prevented or detected.

Our consideration of the Fund’s internal control over financial
reporting was for the limited purpose described in the first paragraph
and would not necessarily disclose all deficiencies in internal control
that might be significant deficiencies or material weaknesses under
standards established by the Public Company Accounting Oversight
Board (United States).  However, we noted no deficiencies in the
Fund’s internal control over financial reporting and its operation,
including controls for safeguarding securities, that we consider to be a
material weakness as defined above as of July 31, 2005.

This report is intended solely for the information and use of
management and the Board of Trustees of Morgan Stanley Health
Sciences Trust, and the Securities and Exchange Commission and is not
intended to be and should not be used by anyone other than these
specified parties.



New York, New York
September 16, 2005