Unfortunately, we cannot see the insects/arthropods clearly enough in the photos to identify them. Are you able to re-take pictures that are clearer? What may help is to position the animal on a light background (for the dark one) or a dark background (for the pale one) and light it well with a camera flash, lamp, or flashlight. Paper or another non-reflective surface will minimize glares of light that can wash-out details. Using a ruler next to it will help us to judge size while also making it easier for the camera to focus on something this finely detailed.

Information on where they were found will also help us to narrow-down candidates among  unrelated insects/arthropods that look very similar to each other. Were they indoors, outdoors, on a person or pet, in a damp or dry area, in clothing or carpet, in a residence or public building, etc.?

Miri

They resemble lice and their location on a worn garment suggests that is a possibility, but we cannot be certain as they are still too hard to see in enough detail. As an example, booklice (not the same insect, despite the name similarity) are another possibility, and in that case would be harmless. We realize it's not easy to get a good photo of something so small, particularly if it's moving. Your video files did not transmit since that is not a file format this system accepts, but we would not necessarily be able to make a diagnosis from them in either case.

We recommend you inquire with a doctor at this point, since we cannot advise on (nor are we experienced with) any medical treatments. If confirmed to be a pest, informing the shelter staff or manager would certainly be prudent. If some of the insects need to be preserved as samples before you can get an appointment, you can try to save some in a vial or zipped bag in some rubbing alcohol or hand sanitizer. It's not a perfect preservative for soft-bodied insects, but it should be sufficient if a dry container would otherwise cause them to desiccate and shrivel or get crushed.

Miri

As noted above, we suggest taking a sample to a doctor or nurse at the health department since we cannot advise on (nor are we experienced with) any medical treatments. If confirmed to be a pest, informing the shelter staff or manager would certainly be prudent. 

If some of the insects need to be preserved as samples before you can get an appointment, you can try to save some in a vial or zipped bag in some rubbing alcohol or hand sanitizer. It's not a perfect preservative for soft-bodied insects, but it should be sufficient if a dry container would otherwise cause them to desiccate and shrivel or get crushed.

Christine