Science is not evidence.
The evidence of viruses is NOT missing. They can be observed directly through a sufficiently powerful microscope. Their presence can be detected by indicators.
A virus is not a particle. It is a complex structure.
Viruses invade cells, causing the cell to make copies of the virus. The normal functioning of that cell is disrupted. The immune system first responds by destroying the cell.
The effects of this damage and the immune system response is the disease, often showing up as congestion, a runny nose, sore throat, etc.
After a few days, antivirus cells matching that virus begin replicating.
After about a week in most cases, the virus is eradicated from the body by antivirus cells, which are capable of doing a much better job than the white blood cells that first responded.
Science is not a method. The dictionary does not define any word. A virus is not a particle.
False authority fallacy.