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18 Jan 2026

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Understanding Communicable Diseases

@uwu_fpjs

Communicable diseases are illnesses that can spread from person to... Show more

# Communicable diseases

A communicable disease is a disease that can be passed on person to person using
different methods. E.g. common col

Communicable Diseases and Their Causes

Ever wondered how you catch a cold? Communicable diseases pass from person to person through various routes. These illnesses can be caused by different types of pathogens that attack our bodies in unique ways.

Viruses are tiny invaders about 100,000 times smaller than bacteria. Unlike bacteria, all viruses are harmful. They invade your cells, multiply inside them, and eventually cause the cells to burst and die. This releases more viruses that attack other cells, continuing the destructive cycle. You often catch viral infections through the air when someone coughs, sneezes, or even talks.

Bacteria come in both helpful and harmful varieties. Good bacteria help maintain your health, treat sewage, and produce medicines and food. They're also vital decomposers in the environment. Harmful bacteria are pathogens that produce toxins as they divide through binary fission, damaging your cells directly. Bacterial infections like gonorrhoea spread through direct contact between people.

Health Alert: Gonorrhoea is a bacterial infection of the sexual organs. You can reduce your risk by avoiding contact with infected sex organs and using protection. If infected, antibiotics can treat the disease.

Diseases spread through three main routes: direct contact (through infected plants, sexual contact, cuts, or animal vectors), water (contaminated food or water entering through the digestive system), and air (breathing in pathogens expelled when people cough, sneeze, or talk).

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Understanding Communicable Diseases

@uwu_fpjs

Communicable diseases are illnesses that can spread from person to person through different methods. These diseases are caused by various pathogens, including viruses, bacteria, fungi, and protists, and understanding how they spread is crucial for preventing infections.

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Communicable Diseases and Their Causes

Health Alert: Gonorrhoea is a bacterial infection of the sexual organs. You can reduce your risk by avoiding contact with infected sex organs and using protection. If infected, antibiotics can treat the disease.