Chembio Commences Clinical Trials for FDA Approval of Its HIV Rapid Tests; Proprietary Lateral Flow Technology Tests to Complete Trials by Fourth Quarter.

BANGKOK, Thailand -- Chembio Diagnostics, Inc., (OTCBB:CEMI.OB) a leading point-of-care diagnostic company, today announced at the Fifteenth World Aids Conference that it has commenced clinical trials of the Sure Check(TM) HIV and HIV Stat-Pak - the company's proprietary lateral flow rapid tests for the detection of antibodies to HIV in finger stick whole blood, serum or plasma. This is the initial step toward a Premarket Approval (PMA) application to the Food & Drug Administration. The clinical trials will be conducted at approved sites throughout the United States, in accordance with an Investigational Device Exemption (IDE), granted by the FDA to the company. Chembio Diagnostics, Inc. expects that the trials will be completed during the fourth quarter of 2004.

Sure Check(TM) HIV and HIV Stat-Pak are used by numerous developing nations throughout the world as a means of screening for HIV and thereby facilitating further preventative measures. By producing results in less than 15 minutes, the number of people who receive their test results increases as they are delivered at the point of care. As a result, the risk of infected people spreading the virus is significantly reduced. The tests have been included in evaluations with the U.S. Centers for Disease Control and the company has initiated strategies to have its tests used in the U.S. Presidential Emergency Plan for Aids Relief (PEPFAR), UN Global Fund initiatives and other global outreach programs.

"Beginning clinical trials for FDA approval marks a significant milestone for Chembio Diagnostics, Inc. and an important benchmark in HIV/AIDS testing technology," says Lawrence A. Siebert, President of Chembio Diagnostics, Inc. "Rapid testing will substantially and positively impact the fight to prevent the spread of HIV. The ability to quickly and accurately inform patients of their HIV status will enable infected patients to immediately begin treatment and substantially improve their quality of life."

Sure Check(TM) HIV was recently evaluated by the Instituto de Diagnostico y Referencia Epidemiologicos ("INDRE"), a leading public health reference laboratory in Mexico, in which Sure Check demonstrated sensitivity and specificity of 100% on a combination of 488 samples from blood donors, high risk patients, and known HIV positive patients. Pursuant to a 13 year technology transfer agreement the HIV Stat-Pak was selected by the Oswaldo Cruz Institute/Bio-Manguinhos, an affiliated entity of the Brazilian Ministry of Health.

For additional information about Sure Check(TM) HIV and HIV Stat-Pak contact Avi Pelossof, Chembio Diagnostics, Inc. at [e-mail].

About Chembio Diagnostics, Inc.

Chembio Diagnostics, Inc. possesses expertise in the development and manufacturing of rapid test products utilizing lateral flow technology. Tests are self-contained, single-use applications that are stable at room temperature and do not require special equipment, making them ideal for use in the field or in any patient care provider setting. Chembio Diagnostics, Inc. (through its subsidiary Chembio Diagnostic Systems, Inc.) has participated in numerous international evaluations of its rapid test products, including the Global AIDS Program - United States Center for Disease Control. Chembio Diagnostics, Inc.'s other proprietary products include the only FDA cleared rapid Lyme disease test. Chembio Diagnostics, Inc. is pursuing distribution strategies with leading agencies and companies, in order to most effectively provide rapid diagnostic treatments for infectious diseases to millions of people worldwide. Chembio Diagnostics, Inc. headquarters are located at 3661 Horseblock Road, Medford, NY 11763. The company's telephone number is 631-924-1135. Email can be directed to [e-mail]. Additional information can be found at www.chembio.com.

Forward Looking Statement

This release contains forward-looking statements regarding Chembio Diagnostics, Inc.'s future plans and expected performance based on assumptions the Company believes to be reasonable. A number of risks and uncertainties could cause actual results to differ materially from these statements, including, without limitation, regulatory approvals and other regulatory actions, successful testing and development of products, actions and pricing of competitors, availability and pricing of intellectual property and other necessary product components, and other risk factors described from time to time in the Company's Form 8-K (of May 2004) and other reports filed with the SEC. In addition, the Company operates in an industry sector where securities values are highly volatile and may be influenced by economic and other factors beyond the Company's control. This press release includes the opinions of Chembio Diagnostics, Inc. and does not necessarily include the views of any other person or entity. This release may not have been reviewed or approved by the operator and/ or participants in any of the projects discussed.