Arthropod vectors are thought to be the primary source of infection, although M. haemofelis is also known to be transmitted from queen to kitten and following blood transfusion. Immunocompromization and/or coinfection with FeLV, FIV, and other Mycoplasma species can exacerbate symptoms or cause symptoms to arise in previously asymptomatic individuals. Symptoms include anemia, lethargy, fever, and anorexia.[5]