Rickets disease is a disorder in the bones (skeletal disorder) which may be caused by the lack of vitamin D, phosphate, or calcium. This can be evidenced through the weakness of the muscles, skeletal deformities, bone pain, etc.
Since, this is caused by lack of vitamins, this is not a caused by the pathogens.
They would burst, as water moves from the hypotonic to hypertonic substances. The red blood cells are hypertonic. They would burst as a result of cytolysis.