Story highlights Aetna sent out letters to some of its customers that revealed their HIV status through the envelope

Law firms sent a formal letter to Aetna, demanding that it change its practices

(CNN) The health care company Aetna mailed envelopes that revealed the HIV status of some of its customers in multiple states, according to the Legal Action Center and the AIDS Law Project of Pennsylvania.

The legal organizations and six other organizations are representing the customers, a group of whom are devastated after friends and neighbors saw the envelopes and learned of their status, the firms said in a news release . Attorneys sent a demand letter to Aetna on Thursday on behalf of those affected, calling on the company to stop sending letters in this format and develop a plan to change its practices.

Aetna said the letters went to about 12,000 customers; the law firms say they have received 23 complaints, with more coming in.

According to the law organizations' release, Aetna's letters included instructions for filling prescriptions and were sent to customers who were taking HIV medications as well as pre-exposure prophylaxis or PrEP, a pill that helps prevent a person from getting HIV. This information was clearly visible through a window on the envelopes.

"I know of someone who has been kicked out of his home because somebody who saw his envelope learned his HIV status," said Sally Friedman, legal director of the Legal Action Center, who is coordinating the efforts of attorneys alongside Ronda B. Goldfein, executive director of the AIDS Law Project of Pennsylvania.

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