HOUSTON - The US Centers for Disease Control and Prevention (CDC) confirmed Sunday that they have brought back a COVID-19 patient who had been released from isolation.

The CDC said that at the time of discharge on Saturday from a healthcare facility in San Antonio, a city in southern Texas, the patient had no symptoms and met all criteria for release, including two negative test results.

However, after the release, the results of a subsequent sample with weakly positive reading were received, prompting the CDC to decide to bring the individual back into isolation out of an abundance of caution.

The CDC explained that there have been similar situations where test results alternate back and forth between negative and positive.

The patient had some contact with others after discharge. Local public health officials are following up to trace possible exposures and notify them of the potential risk.

In a statement issued on Sunday, Mayor of San Antonio Ron Nirenberg said it is "unacceptable" that the CDC allowed the public to be exposed to a patient with a positive COVID-19 reading.

As of 9 am Sunday (1500 GMT), there were 62 confirmed novel coronavirus cases in the United States, data from the World Health Organization shows.