COVID-19 testing swabs are typically made out of synthetic fibers such as polyester, rayon, viscose and nylon. These materials have been proven to be safe as well as effective at absorbing fluids and detecting pathogens like COVID-19. Scientists use many of the same and similar test swabs to clinically sample for other diseases.

Every object we encounter on this planet is holding an electric "charge" — a balance of electricity that's unique to that object. Some charges are classified as negative charges. Others are classified as positive. The categorization has to do with the composition of atoms in an object: some objects have mostly negative energy atoms, others mostly positive energy atoms, and some are neutral.

The way an item is charged (positive, negative or neutral) determines how it interacts with the world—or rather, the other charged items around it. Opposite charges attract each other, like charges repel each other, and any charge—positive or negative—attracts a neutral charge.

Sometimes, objects can hold an imbalance of negative and positive charges, which build up on an object’s surface until they find a way to be released. That's called static electricity. Think of rubbing a balloon on thin, straight hair. The rubbing creates an imbalance of charges and causes the hair to move around, seemingly magically. Such may be the case with videos of COVID-19 swabs moving around, especially as they're being pulled apart.

In particular, if there is more than one type of synthetic fiber in an object, which is sometimes the case with COVID-19 testing swabs, there is likely to be even more static. That's because multiple materials are rubbing up against each other. When you pull fibers apart—as individuals are doing in the videos they’re recording to try and make the false claim that fibers are ‘alive'— movement from static increases even more, making the fibers more negatively charged. This negative charge makes the fibers likely to move around a lot when placed near another negatively charged object like meat, because like charges repel.

Opposite charges also attract, which means the fibers from the testing swab may be likely to move around a lot when placed near metal or even a neutrally charged material like wood. The fibers are trying to get closer to these materials because of their atomic compositions.

Similar to swabs, there are also no living fibers or worms in surgical face masks. Surgical face masks are typically made with polypropylene—a type of fabric made from a “thermoplastic” polymer (thermoplastic means it’s easy to work with and shape at high temperatures). Surgical masks can also be made of polystyrene, polycarbonate, polyethylene, or polyester— all of which are types of fabrics derived from thermoplastic polymers. Surgical masks are safe and recommended for the public to wear to help prevent the spread of COVID-19. 

Any strands in face masks that appear to be moving on their own under a microscope are regular, textile fibers that make up a large portion of house dust. Fibers can either appear to move on their own due to static, as discussed above, or moisture. When fibers absorb moisture, either through breath or by adding water, the fibers change shape. In these cases they can appear to move on their own as small movements are either made in the water through tiny air currents that can’t be felt by humans, or as the water dries out and the fibers shape changes as water evaporates.

These fibers appear as standalone, making them look more like "worms" to some, because they are darker and contrast with the color of the mask. It’s possible that there are other fibers on the mask moving as well that can’t be seen, because of their light color.

Real microscopic worms would not be able to survive in or on a face mask. Worms need to be surrounded by water and the environment of a face mask is too dry. In addition, real worms look very different under a microscope than fibers, with visible organs and other distinguishable characteristics.

Videos have been circulating online claiming that the fibers on COVID-19 testing swabs and fibers in face masks are “alive,” contain nanoparticles, or cause Morgellons disease. These videos are being used to promote sentiments against COVID-19 testing and face mask use. The claims have no scientific basis, and the "experiments" conducted in these videos were not controlled and conducted with scientific rigor. Any movement of fibers from COVID-19 testing swabs can be attributed primarily to static electricity, and any movement of fibers from face masks can be attributed primarily to moisture. Notably, most of the videos observing face masks under a microscope claiming that there were live "worms" or parasites in them had moistened the mask before or while observing it.

Nanoparticles are microscopic particles less than 100nm in one dimension, that are not visible to the human eye. Just like any other chemical substance, some nanomaterials are hazardous and some are not. Morgellons disease is a disproven skin condition involving the presence of multicolored distortions that project from skin. It's accompanied by the feeling of itching and crawling under the skin. Some physicians believe the condition to be a form of delusion, and others believe it to be a legitimate condition stemming from infection and other potential causes. 

If concerned about nanoparticles or Morgellons disease, it is understandable to want to try and identify a source. However, there is no evidence that COVID-19 testing swabs or face masks are connected to either.