Meredith Celeste Keltner, 28 of Carlisle, was last seen on March 28 and last responded to a text message on April 7, according to a release from PSP.
She has no fixed home address but typically stays in Carlisle Borough and York City, predominately in homeless shelters, homeless camps and hotels/motels, say police.
She does not have a working phone, but has always kept in close contact with family.
She is known to suffer from mental health issues, possible illegal drug use and has a compromised immune system.
Anyone with information is encouraged to contact PSP Carlisle at 717-249-2121.
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