Sickle cell disease (sickle cell anemia) is a genetic, inherited disease affecting red blood cells, in which a child can be ill if both parents are transmitters, ie asymptomatic carriers of the gene for sickle cell disease. It is a hereditary autosomal recessive disease, that is, it affects girls as well as boys, and only manifests itself when one carries two genes of the disease. This disease is genetic and therefore not contagious.
*So, to be sick from sickle cell disease, the person has to have two sick alleles in the chromosome.
*To have the sickle-cell trait without getting sick, the person has to have only one sick allele.