What are Infectious Diseases?
Infectious diseases are caused by harmful microorganisms such as bacteria, viruses, fungi, and parasites. These diseases can spread from person to person, through contaminated food or water, insect bites, or exposure to infected surfaces. While some infections are mild and self-limiting, others can be severe or even life-threatening if not treated promptly.
Causes of Infectious Diseases
- Bacteria – Single-celled organisms that can cause infections like pneumonia, tuberculosis (TB), and urinary tract infections (UTIs).
- Viruses – Tiny pathogens that invade cells and cause diseases such as the flu, HIV, hepatitis, and COVID-19.
- Fungi – Can lead to skin infections, lung infections, and systemic fungal diseases
- Parasites – Organisms like malaria, tapeworms, and giardia that live in or on a host and cause infections.
Common Symptoms of Infectious Diseases
- Fever – A common sign of an infection as the body fights off pathogens.
- Cough & Sore Throat – Often seen in respiratory infections like pneumonia, flu, and COVID-19.
- Fatigue & Weakness – Common in viral and bacterial infections.
- Body Aches & Joint Pain – Can occur in viral fevers, dengue, and chikungunya.
- Difficulty Breathing – A symptom of severe infections such as pneumonia and tuberculosis.
- Abdominal Pain, Nausea & Diarrhea – Common in gastrointestinal infections.
