The vaccine-strain measles virus lacks the PEA motif (P64, E89, A209) in the M protein, which is associated with neurotropism and SSPE risk. Instead, vaccine strains contain SKT or PKT motifs that are not linked to central nervous system infection or SSPE. This distinction is critical for the safety profile of the measles vaccine, as it significantly reduces the risk of SSPE. The absence of these molecular markers in the vaccine-strain measles virus is a key factor in its inability to cause SSPE, making the vaccine a safe and effective tool for preventing measles and its complications, including SSPE.
What molecular markers does the vaccine-strain measles virus lack?
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