Why Are There Currently No Vaccines Against Streptococcus Pyogenes

question 31

Multiple Choice

Why are there currently no vaccines against Streptococcus pyogenes?

• A) There are many antigenic types in the M protein of this organism. A vaccine against one type might not protect against another.
• B) There is great variation in the polysaccharide capsule of this organism. A vaccine against one type might not protect against another.
• C) Antibodies to streptococcal M protein may also recognize and bind to myosin in the heart, causing autoimmunity and leading to rheumatic fever.
• D) There is great variation in the M protein of this organism. A vaccine against one M type might not protect against another AND antibodies to streptococcal M protein may also recognize and bind to myosin in the heart, causing autoimmunity and leading to rheumatic fever.
• E) There is great variation in the polysaccharide capsule of this organism. A vaccine against one type might not protect against another AND antibodies to streptococcal M protein may also recognize and bind to myosin in the heart, causing autoimmunity and leading to rheumatic fever.

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Definitions:

Tendon

A fibrous connective tissue that attaches muscle to bone, enabling movement by transmitting the force generated by the muscle.

Diaphragm

A dome-shaped muscular partition separating the thorax from the abdomen in mammals, playing a major role in breathing by contracting and flattening to enlarge the thoracic cavity.

Orbicularis Oris

A complex of muscles in the lips that encircles the mouth, enabling it to close, pucker, and articulate words and expressions.

Diaphragm

A muscular and tendinous sheet that separates the chest cavity from the abdominal cavity and plays a major role in breathing.