Chembio Diagnostics Inc. on Thursday reported a loss for the final three months of 2013 on falling sales of its rapid tests for the AIDS virus and syphilis.
The Medford-based manufacturer said it lost $262,000 in the October-December period compared with a profit of $492,000 a year earlier.
Sales in the fourth quarter dropped a tenth of 1 percent to $7.86 million.
Lawrence Siebert, Chembio's chief executive, said it was "experiencing particularly strong demand" for a combination HIV-syphilis test introduced into Mexico in late 2013.
For the year ended Dec. 31, Chembio reported a 44 percent decline in profit to $531,000. Sales rose 15 percent to nearly $30 million.
Siebert said the company was focused on meeting increased demand for rapid medical tests in foreign countries and boosting its domestic sales. He said, "A key strategic investment for Chembio is establishing a commercial sales organization in the U.S. to market Chembio-branded products."
The company employs about 210 people in Medford and recently rented 21,450 square feet in Holtsville to expand production.
Chembio released its financial results before the stock market's opening. In early NASDAQ trading, the company's sales were down more than 3 percent to $3.61.