A second mechanism for evasion is antigenic variation. Trypanosoma brucei is an excellent example of this. In this scenario, the tripanosomes are initially destroyed by host antibody. However, the organism resurfaces in the body with a different set of antigens or glycoproteins. The process continues, and the parasite possesses a number of genes that code for these antigens and can vary the genes used. Eventually, the paracite succeeds and avoids host elimination. This type of variation is known as phenotypic variation and differs from genotypic variation seen in influenza epidemics.
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