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<SEC-DOCUMENT>0000930413-05-008702.txt : 20051230
<SEC-HEADER>0000930413-05-008702.hdr.sgml : 20051230
<ACCEPTANCE-DATETIME>20051230153909
ACCESSION NUMBER:		0000930413-05-008702
CONFORMED SUBMISSION TYPE:	NSAR-B
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20051031
FILED AS OF DATE:		20051230
DATE AS OF CHANGE:		20051230
EFFECTIVENESS DATE:		20051230

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BlackRock Health Sciences Trust
		CENTRAL INDEX KEY:			0001314966
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		NSAR-B
		SEC ACT:		1940 Act
		SEC FILE NUMBER:	811-21702
		FILM NUMBER:		051294533

	BUSINESS ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809
		BUSINESS PHONE:		(888) 825-2257

	MAIL ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809
</SEC-HEADER>
<DOCUMENT>
<TYPE>NSAR-B
<SEQUENCE>1
<FILENAME>c40240-bme.fil
<TEXT>
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SIGNATURE   HENRY GABBAY
TITLE       TREASURER

</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.77B
<SEQUENCE>2
<FILENAME>c40240_ex99-77b.txt
<TEXT>

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Directors and Trustees and Shareholders of
  The BlackRock Closed-End Funds

<TABLE>
<CAPTION>
<S>                                              <C>
BlackRock S&P Quality Rankings Global Equity     BlackRock Dividend Achievers(TM) Trust
   Managed Trust
BlackRock Global Opportunities Equity Trust      BlackRock Global Energy and Resources Trust
BlackRock Enhanced Dividend Achievers(TM)        BlackRock Heath Sciences Trust
   Trust
BlackRock World Investment Trust                 BlackRock Strategic Dividend Achievers(TM) Trust
                                                 (each a "Trust" and collectively, the "Trusts")
</TABLE>


In planning and performing our audits of the financial statements of the
BlackRock Closed-End Funds listed above as of and for the year ended October 31,
2005 in accordance with the Standards of the Public Company Accounting Oversight
Board (United States), we considered their 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 opinions
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
Trusts' internal control over financial reporting. Accordingly, we express no
such opinion.

The management of the Trusts is responsible for establishing and maintaining
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 affect the Trust'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 Trust'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 or the annual or
interim financial statements will not be prevented or detected.

Our consideration of the Trusts' 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 Trusts' internal controls over
financial reporting and its operation, including controls for safeguarding
securities, that we consider to be a material weakness as defined above as of
October 31, 2005.

This report is intended solely for the information and use of management and the
Board of the BlackRock Closed-End Funds of the Trusts and the Securities and
Exchange Commission and is not intended to be and should not be used by anyone
other than these specified parties.


/s/ Deloitte & Touche LLP


Registered Public Accounting Firm
Boston, Massachusetts
December 30, 2005





</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
