[ 347 ] Life Science GED ® TEST SCIENCE FLASH REVIEW • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Refer to the following passage to answer the next three questions. Tetanus is a non-contagious infection caused by rod-shaped, anaerobic bacteria, Clostridium tetani, or C. tetani, which affects skeletal muscles by releasing an endotoxin manufactured in the outer portion of the cell wall. The toxin infects the central nervous system and causes prolonged muscle spasms. Infection occurs through contamination of wounds and can be prevented by proper immunization. Most developed countries provide tetanus vaccinations as a standard of health care. Often, tetanus is associated with rust. Rusting occurs when oxygen, water, and iron interact in a process called oxidation. Over time, the iron mass will convert to iron oxide, or rust. A rusted surface provides a thriving environment for organisms with low-oxygen needs. Tetanus occurs worldwide, but is most common in hot, damp climates with manure-treated soils. C. tetani endospores are widely distributed in the intestines of many animals such as cattle, chickens, and sheep. very strongly prevalent strongly prevalent prevalent a few cases rare, very few cases Explain how a non-contagious disease, such as tetanus, comes to be so widespread in certain parts of the world. Include multiple pieces of evidence from the text to support your answer.