Emergency alert systems and methods based on motion detection

A monitoring unit in an emergency alert system, comprising:

• a housing;
• a motion sensor positioned within the housing and configured to detect motion within a monitoring area, wherein the motion sensor consists of passive infrared detection so that the motion sensor lacks an ability to capture images or video, whereby privacy of the monitoring area is protected;
• a communication device configured to electronically communicate with one or more remote electronic devices;
• and
• a microcomputer coupled to the communication device and the motion sensor, the microcomputer comprising:
• a memory device storing instructions;
• and
• a processing device configured to execute the instructions to:
• determine motion data from the motion sensor, the motion data representing movement and lack of movement by a subject in the monitoring area, irrespective of a posture of the subject,
• determine that the lack of movement occurs within a monitoring period,
• determine that a duration of the lack of movement exceeds a threshold, and
• transmit an electronic alert message to the one or more remote electronic devices using the communication device only if the duration of the lack of movement exceeds said threshold, wherein the electronic alert message indicates a potential emergency based on the lack of movement.