Question: How does one get carpet beetles and how does one get rid of them?

ANSWER  There are several carpet beetle species that can occur in houses.  The most common of these is the furniture carpet beetle, Anthrenus flavipes.  This is a small beetle (a little larger than the head of a pin), that is somewhat oval in shape and has a mixture of black and gray patches.  It is characterized by moving very slowly, and rolling over as if dead when touched.  The larvae of these beetles have brown bands and long ”hairs” at the end of their body.  The adults are most often seen on walls moving very slowly.  They are active in summer and relatively inactive in the winter.
Carpet beetles are a common household pest.  They can feed on a wide variety of things, from wool, leather, and other animal products to noodles and flour, meal, and other stored food and plant products.  This feeding habit also makes them difficult to control.  They can almost any part of a house.

The best control strategy is to do a thorough vacuuming of the suspected infested sites.  Then do a thorough cleaning, which includes looking for all the material that could be infested.  In the kitchen, discard any infested food. In the bedroom, dry clean infested woolen garments and store carefully.

Spraying insecticides for carpet beetles may be useful.  If the infestation is heavy, treat the cracks and crevices in the area where you have seen them. An application around the outside foundation can help keep adults from moving inside.

Make sure doors close snugly and have weatherstripping. Check window screens to be sure they fit properly. Since some adult carpet beetles eat pollen and nectar, it might help to inspect any flowers that you bring into the house.