#AP Environmental Science: Infectious Diseases - The Night Before 🦠

Hey! Let's get you prepped for the exam. We're going to break down infectious diseases, focusing on what's most likely to show up on the test. Think of this as your cheat sheet – quick, clear, and to the point. Let's do this!

#1. Introduction to Pathogens and Infectious Diseases

• Pathogens: Think of these as tiny invaders. They have different ways of getting into our bodies:
  • Direct Contact: Touching someone who's sick.
  • Inhalation: Breathing in infected droplets.
  • Ingestion: Eating or drinking contaminated stuff.
• Infectious Diseases: These are the illnesses caused by pathogens. Examples: flu, tuberculosis, cholera, HIV.
• Historical Impact: Pathogens have caused huge epidemics (like the bubonic plague) and pandemics (like COVID-19).
• Prevention is Key: Good hygiene, vaccines, clean water, and sanitation are crucial.

#2. Specific Diseases: A Closer Look

#2.1 Plague

Pay close attention to the transmission and forms of plague, as this is a classic example often used in exam questions.

• Cause: Yersinia pestis bacteria.
• Transmission:
  • Flea Bites: Usually from infected rodents.
  • Handling Infected Animals: Be careful!
  • Inhaling Droplets: From infected people or animals.
• Forms:
  • Bubonic: Swollen lymph nodes (buboes), fever, chills.
  • Septicemic: Bloodstream infection, organ failure.
  • Pneumonic: Lung infection, airborne transmission.
• History: The Black Death was a major plague pandemic.
• Current Status: Rare but still present in some regions. Treatable with antibiotics.
• Prevention: Sanitation, rodent control, public education.

#2.2 Malaria

Malaria is a high-impact topic due to its global health significance and the complexities of its transmission and control.

• Cause: Plasmodium parasite.
• Transmission: Bite of infected Anopheles mosquitoes.
• Symptoms: Fever, chills, headache, muscle...