Hundreds of people taking HIV tests at New York clinics between November 2007 and April of this year were mistakenly informed they were HIV-positive, the New York City Health Department, said, according to an article published on Sunday in the New York Post.

About 232 people were involved in this situation. They took a mouth swab test to check for HIV, which results came back positive. They further took a blood test, which revealed they were HIV negative.

The U.S. Food and Drug Administration approved the mouth swab test on March 26, 2004. The advantage of this test is that it can be done without a needle. The manufacturer of this test is OraSure Technologies. The test, called the OraQuick Rapid HIV Test for Oral Fluid provides results in 20 minutes using saliva. This test can detect only HIV type 1 (HIV-1) antibodies.

The company is currently under an investigation run by the Department of Health and the U.S. Centers for Disease Control and Prevention. Also, the company itself is trying to figure out what exactly has led to this unfortunate situation.

Meanwhile, the Department of Health has stopped using the OraSure swab test.

Assistant Health Commissioner Dr. Susan Blank told the Post that “nobody was misled or harmed,” at least physically, the patients being provided a blood test to know for sure if they were infected with the HIV virus.