1. Why do Coxiella show variable Gram stain results-that is, why would they stain gram-positive or gram-negative at different times? Tell which stage is G + and which stage is G-, Also, explain if Coxiella should be classified as gram-positive or gram-negative when classified?

2. What disease does C. burnetii cause? Why can this disease be transmitted by airborne routes while other (closely related) rickettsia species require insects and ticks for transmission to humans? Give an example of a closely related rickettsia species to Coxiella burnetii and tell how it is transmitted.