How do doctors know that Lyme disease is caused by a bacterium and NOT a virus?

Doctors can diagnose the disease through physical findings such as a "bull's-eye" rash along with a history of symptoms. But not everyone has the rash, and not everyone can recall being bitten. Special blood tests can be taken three to four weeks after suspected contact to confirm the diagnosis.

Explanation: HOPE THIS HELPS HAVE A GOOD DAY!;)

dynamic equilibrium is the answer.