The FEHBlog’s featured image for certain recent posts has been a CDC picture of the COVID-19 virus. The Great Influenza book that the FEHBlog has been reading includes this explanation of the picture:

The virus itself is nothing more than a membrane—a sort of envelope—that contains the genome, the genes that define what the virus is. It is usually spherical (it can take other shapes), about 1/10,000 of a millimeter in diameter, and it looks something like a dandelion with a forest of two different-shaped protuberances—one roughly like a spike, the other roughly like a tree—jutting out from its surface. These protuberances provide the virus with its actual mechanism of attack [as viruses invade the body’s cells]. That attack, and the defensive war the body wages, is typical of how shape and form determine outcomes.

Barry, John M.. The Great Influenza (p. 103). Penguin Publishing Group. Kindle Edition.